J. Conway

We establish the existence of the top quark using a 67 pb^-1 data sample of Pbar-P collisions at Sqrt(s) = 1.8 TeV collected with the Collider Detector at Fermilab (CDF). Employing techniques similar to those we previously published, we observe a signal consistent with t-tbar decay to WW b-bbar, but inconsistent with the background prediction by 4.8 sigma. Additional evidence for the top quark is provided by a peak in the reconstructed mass distribution. We measure the top quark mass to be 176 +/-8(stat) +/- 10(sys.) GeV/c^2, and the t-tbar production cross section to be 6.8 +3.6 -2.4 pb.

We present the results of a search for the top quark in 19.3 pb−1 of p¯p collisions at √s =1.8 TeV. The data were collected at the Fermilab Tevatron collider using the Collider Detector at Fermilab (CDF). The search includes standard model tt¯ decays to final states eeνν¯, eμνν¯, and μμνν¯ as well as e+ν+jets or μ+ν+jets. In the (e,μ)+ν+jets channel we search for b quarks from t decays via secondary vertex identification and via semileptonic decays of the b and cascade c quarks. In the dilepton final states we find two events with a background of 0.56+0.25−0.13 events. In the e,μ+ν+jets channel with a b identified via a secondary vertex, we find six events with a background of 2.3±0.3. With a b identified via a semileptonic decay, we find seven events with a background of 3.1±0.3. The secondary vertex and semileptonic-decay samples have three events in common. The probability that the observed yield is consistent with the background is estimated to be 0.26%. The statistics are too limited to firmly establish the existence of the top quark; however, a natural interpretation of the excess is that it is due to tt¯ production. We present several cross-checks. Some support this hypothesis; others do not. Under the assumption that the excess yield over background is due to tt¯, constrained fitting on a subset of the events yields a mass of 174±10+13−12 GeV/c2 for the top quark. The tt¯ cross section, using this top quark mass to compute the acceptance, is measured to be 13.9+6.1−4.8 pb.Received 25 April 1994DOI:https://doi.org/10.1103/PhysRevD.50.2966©1994 American Physical Society

We present the results of a study of muon pairs with invariant masses greater than 4.05 GeV/${c}^{2}$ produced in high-energy pion-nucleon interactions. The production cross section together with the inferred pion and nucleon structure functions are reported and compared with other experiments and with QCD predictions. The transverse-momentum distributions are also presented. Finally, the full angular distribution in cos\ensuremath{\theta} and \ensuremath{\varphi} is given as a function of mass, Feynman x, and transverse momentum. Longitudinal photon polarization is seen in the lower portion of the mass range at high ${x}_{\ensuremath{\pi}}$. This result is compared with a higher-twist model.

We summarize a search for the top quark with the Collider Detector at Fermilab (CDF) in a sample of $\bar{p}p$ collisions at $\sqrt{s}$= 1.8 TeV with an integrated luminosity of 19.3~pb$^{-1}$. We find 12 events consistent with either two $W$ bosons, or a $W$ boson and at least one $b$ jet. The probability that the measured yield is consistent with the background is 0.26%. Though the statistics are too limited to establish firmly the existence of the top quark, a natural interpretation of the excess is that it is due to $t\bar{t}$ production. Under this assumption, constrained fits to individual events yield a top quark mass of $174 \pm 10^{+13}_{-12}$ GeV/c$^2$. The $t\bar{t}$ production cross section is measured to be $13.9^{+6.1}_{-4.8}$~pb. (Submitted to Physical Review Letters on May 16, 1994).

We present a new measurement of the inclusive forward-backward $t\overline{t}$ production asymmetry and its rapidity and mass dependence. The measurements are performed with data corresponding to an integrated luminosity of $5.3\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of $p\overline{p}$ collisions at $\sqrt{s}=1.96\text{ }\text{ }\mathrm{TeV}$, recorded with the CDF-II Detector at the Fermilab Tevatron. Significant inclusive asymmetries are observed in both the laboratory frame and the $t\overline{t}$ rest frame, and in both cases are found to be consistent with $CP$ conservation under interchange of $t$ and $\overline{t}$. In the $t\overline{t}$ rest frame, the asymmetry is observed to increase with the $t\overline{t}$ rapidity difference, $\ensuremath{\Delta}y$, and with the invariant mass ${M}_{t\overline{t}}$ of the $t\overline{t}$ system. Fully corrected parton-level asymmetries are derived in two regions of each variable, and the asymmetry is found to be most significant at large $\ensuremath{\Delta}y$ and ${M}_{t\overline{t}}$. For ${M}_{t\overline{t}}\ensuremath{\ge}450\text{ }\text{ }\mathrm{GeV}/{c}^{2}$, the parton-level asymmetry in the $t\overline{t}$ rest frame is ${A}^{t\overline{t}}=0.475\ifmmode\pm\else\textpm\fi{}0.114$ compared to a next-to-leading order QCD prediction of $0.088\ifmmode\pm\else\textpm\fi{}0.013$.

We present a study of J/ψ and ψ(2S) production in p¯p collisions, at √s=1.8TeV with the CDF detector at Fermilab. The J/ψ and ψ(2S) mesons are reconstructed using their μ+μ− decay modes. We have measured the inclusive production cross section for both mesons as a function of their transverse momentum in the central region, |η|<0.6. We also measure the fraction of these events originating from b hadrons. We thus extract individual cross sections for J/ψ and ψ(2S) mesons from b-quark decays and prompt production. We find a large excess (approximately a factor of 50) of direct ψ(2S) production compared with predictions from the color singlet model.Received 3 February 1997DOI:https://doi.org/10.1103/PhysRevLett.79.572©1997 American Physical Society

We have observed bottom-charm mesons B_c via the decay mode Bc -&gt; J/psi lepton neutrino in 1.8 TeV p-bar p collisions using the CDF detector at the Fermilab Tevatron. A fit of background and signal contributions to the J/psi + lepton mass distribution yielded 20.4 +6.2 -5.5 events from B_c mesons. A fit to the same distribution with background alone was rejected at the level of 4.8 standard deviations. We measured the B_c mass to be 6.40 +- 0.39 +- 0.13 GeVc^2 and the B_c lifetime to be tau(B_c) = 0.46 +0.18 -0.16 +- 0.03 ps. We measured the production cross section times branching ratio for B_c -&gt; J/psi lepton neutrino relative to that for B+ -&gt; J/psi K to be 0.132 +0.041 -0.037 (stat) +- 0.031 (syst) +0.032 -0.020 (lifetime).

We have measured the fraction of $J/\ensuremath{\psi}$ mesons originating from ${\ensuremath{\chi}}_{c}$ meson decays in $p\overline{p}$ collisions at $\sqrt{s}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1.8\mathrm{TeV}$. The fraction, for ${P}_{T}^{J/\ensuremath{\psi}}&gt;4.0\mathrm{GeV}/c$ and $|{\ensuremath{\eta}}^{J/\ensuremath{\psi}}|&lt;0.6$, not including contributions from $b$ flavored hadrons, is $29.7%\ifmmode\pm\else\textpm\fi{}1.7%(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}5.7%(\mathrm{syst})$. We have determined the cross sections for $J/\ensuremath{\psi}$ mesons originating from ${\ensuremath{\chi}}_{c}$ decays and for directly produced $J/\ensuremath{\psi}$ mesons. We have found that direct $J/\ensuremath{\psi}$ production is in excess of the prediction of the color singlet model by the same factor found for direct $\ensuremath{\psi}(2S)$ production.

We report the observation of bottom-charmed mesons ${B}_{c}$ in 1.8 TeV $p\overline{p}$ collisions using the CDF detector at the Fermilab Tevatron. The ${B}_{c}$ mesons were found through their semileptonic decays, ${B}_{c}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\rightarrow}J/\ensuremath{\psi}{l}^{\ifmmode\pm\else\textpm\fi{}}X.$ A fit to the $J/\ensuremath{\psi}l$ mass distribution yielded ${20.4}_{\ensuremath{-}5.5}^{+6.2}$ events from ${B}_{c}$ mesons. A test of the null hypothesis, i.e., an attempt to fit the data with background alone, was rejected at the level of 4.8 standard deviations. By studying the quality of the fit as a function of the assumed ${B}_{c}$ mass, we determined ${M(B}_{c})=6.40\ifmmode\pm\else\textpm\fi{}0.39(\mathrm{stat}.)\ifmmode\pm\else\textpm\fi{}0.13\mathrm{}(\mathrm{syst})\mathrm{}\mathrm{GeV}{/c}^{2}.$ From the distribution of trilepton intersection points in the plane transverse to the beam direction we measured the ${B}_{c}$ lifetime to be $\ensuremath{\tau}{(B}_{c}{)=0.46}_{\ensuremath{-}0.16}^{+0.18}(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.03\mathrm{}(\mathrm{syst})\mathrm{}\mathrm{ps}.$ We also measured the ratio of production cross section times branching fraction for ${B}_{c}^{+}\ensuremath{\rightarrow}J/\ensuremath{\psi}{l}^{+}\ensuremath{\nu}$ relative to that for ${B}^{+}\ensuremath{\rightarrow}J/\ensuremath{\psi}{K}^{+}$ to be $\frac{\ensuremath{\sigma}{(B}_{c})\ifmmode\times\else\texttimes\fi{}{B(B}_{c}\ensuremath{\rightarrow}J/\ensuremath{\psi}l\ensuremath{\nu})}{\ensuremath{\sigma}(B)\ifmmode\times\else\texttimes\fi{}B(\stackrel{\ensuremath{\rightarrow}}{B}J/\ensuremath{\psi}K)}{=0.132}_{\ensuremath{-}0.037}^{+0.041}{(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.031\mathrm{}(\mathrm{syst})}_{\mathrm{\ensuremath{-}}0.020}^{+0.032}(\mathrm{lifetime}).$

We have measured the polarization of J/psi and psi(2S) mesons produced in pp collisions at sqrt[s] = 1.8 TeV, using data collected at the Collider Detector at Fermilab during 1992-1995. The polarization of promptly produced J/psi [psi(2S)] mesons is isolated from those produced in B-hadron decay, and measured over the kinematic range 4 [5.5]<P(T)<20 GeV/c and |y|<0.6. For P(T) greater than or approximately equal 12 GeV/c we do not observe significant polarization in the prompt component.

The growth and development of ``charged particle jets'' produced in proton-antiproton collisions at $1.8 \mathrm{TeV} $ are studied over a transverse momentum range from $0.5$ $\mathrm{GeV}/c$ to $50$ $\mathrm{GeV}/c.$ A variety of leading (highest transverse momentum) charged jet observables are compared with the QCD Monte Carlo models HERWIG, ISAJET, and PYTHIA. The models describe fairly well the multiplicity distribution of charged particles within the leading charged jet, the size of the leading charged jet, the radial distribution of charged particles and transverse momentum around the leading charged jet direction, and the momentum distribution of charged particles within the leading charged jet. The direction of the leading ``charged particle jet'' in each event is used to define three regions of $\ensuremath{\eta}\ensuremath{-}\ensuremath{\varphi}$ space. The ``toward'' region contains the leading ``charged particle jet,'' while the ``away'' region, on the average, contains the away-side jet. The ``transverse'' region is perpendicular to the plane of the hard $2$-to-$2$ scattering and is very sensitive to the ``underlying event'' component of the QCD Monte Carlo models. HERWIG, ISAJET, and PYTHIA with their default parameters do not describe correctly all the properties of the ``transverse'' region.

We report an indirect search for nonstandard model physics using the flavor-changing neutral current decays B→K(*)μ(+)μ(-). We reconstruct the decays and measure their angular distributions, as a function of q(2)=M(μμ)(2)c(2), where M(μμ) is the dimuon mass, in pp¯ collisions at √s=1.96 TeV using a data sample corresponding to an integrated luminosity of 6.8 fb(-1). The transverse polarization asymmetry A(T)(2) and the time-reversal-odd charge-and-parity asymmetry A(im) are measured for the first time, together with the K* longitudinal polarization fraction F(L) and the muon forward-backward asymmetry A(FB) for the decays B(0)→K(*0)μ(+)μ(-) and B(+)→K(*+)μ(+)μ(-). The B→K*μ(+)μ(-) forward-backward asymmetry in the most sensitive kinematic regime, 1≤q(2)<6 GeV(2)/c(2), is measured to be A(FB)=0.29(-0.23)(+0.20)(stat)±0.07(syst), the most precise result to date. No deviations from the standard model predictions are observed.

We report a study of the invariant mass distribution of jet pairs produced in association with a W boson using data collected with the CDF detector which correspond to an integrated luminosity of 4.3 fb(-1). The observed distribution has an excess in the 120-160 GeV/c(2) mass range which is not described by current theoretical predictions within the statistical and systematic uncertainties. In this Letter, we report studies of the properties of this excess.

We report the first observation of the baryonic flavor-changing neutral current decay Λ(b)(0)→Λμ(+)μ(-) with 24 signal events and a statistical significance of 5.8 Gaussian standard deviations. This measurement uses a pp collisions data sample corresponding to 6.8 fb(-1) at √s = 1.96 TeV collected by the CDF II detector at the Tevatron collider. The total and differential branching ratios for Λ(b)(0)→Λμ(+)μ(-) are measured. We find B(Λ(b)(0)→Λμ(+)μ(-))=[1.73 ± 0.42(stat) ± (syst)] × 10(-6). We also report the first measurement of the differential branching ratio of B(s)(0)→ϕμ(+)μ(-), using 49 signal events. In addition, we report branching ratios for B(+)→K(+)μ(+)μ(-), B(0)→K(0)μ(+)μ(-), and B→K(*)(892)μ(+)μ(-) decays.

We have measured the W-boson mass MW using data corresponding to 2.2/fb of integrated luminosity collected in proton-antiproton collisions at 1.96 TeV with the CDF II detector at the Fermilab Tevatron collider. Samples consisting of 470126 W->enu candidates and 624708 W->munu candidates yield the measurement MW = 80387 +- 12 (stat) +- 15 (syst) = 80387 +- 19 MeV. This is the most precise measurement of the W-boson mass to date and significantly exceeds the precision of all previous measurements combined.

We have searched for heavy neutral gauge bosons (Z′) in dielectron and dimuon decay modes using 110pb−1 of ¯pp collisions at √s=1.8TeV collected with the Collider Detector at Fermilab. We present a limit on the production cross section times branching ratio of a Z′ boson decaying into dileptons as a function of Z′ mass. For mass MZ′>600GeV/c2, the upper limit is 40 fb at 95% confidence level. We set the lower mass limits of 690, 590, 620, 595, 565, 630, and 600GeV/c2 for Z′SM, Zψ, Zη, Zχ, ZI, ZLR, and ZALRM, respectively.Received 6 May 1997DOI:https://doi.org/10.1103/PhysRevLett.79.2192©1997 American Physical Society

We report on measurements of the Upsilon(1S), Upsilon(2S), and Upsilon(3S) differential cross sections (d(2)sigma/dp(T)dy)(/y/<0.4), as well as on the Upsilon(1S) polarization in p p macro collisions at square root of s = 1.8 TeV using a sample of 77+/-3 pb(-1) collected by the collider detector at Fermilab. The three resonances were reconstructed through the decay Upsilon-->mu(+)mu(-). The measured angular distribution of the muons in the Upsilon(1S) rest frame is consistent with unpolarized meson production.

We search for the flavor-changing neutral current decays of the top quark t→qγ and t→qZ (here q represents the c and u quarks) in ¯pp collisions at √s=1.8TeV. We use a dataset (∫Ldt∼110pb−1) collected during the 1992–1995 run of the Collider Detector at Fermilab. We set 95% confidence level limits on the branching fractions B(t→qγ)<3.2% and B(t→qZ)<33%, consistent with the standard model.Received 24 July 1997DOI:https://doi.org/10.1103/PhysRevLett.80.2525©1998 American Physical Society

The transverse momentum and total cross section of e^+e^- pairs in the Z-boson region of 66<M_{ee}<116 GeV$/c^2$ from $p\bar{p}$ collisions at $\sqrt{s}=1.8$ TeV are measured using 110 pb^{-1} of collisions taken by the Collider Detector at Fermilab during 1992-1995. The total cross section is measured to be $248 \pm 11$ pb. The differential transverse momentum cross section is compared with calculations that match quantum chromodynamics perturbation theory at high transverse momentum with the gluon resummation formalism at low transverse momentum.

This paper presents the first direct measurement of the $B$ meson differential cross section, $d\sigma/dp_T$, in $p\bar{p}$ collisions at $\sqrt{s}=1.8$ TeV using a sample of $19.3 \pm 0.7$ pb$^{-1}$ accumulated by the Collider Detector at Fermilab (CDF). The cross section is measured in the central rapidity region $|y| < 1$ for $p_T(B) > 6.0$ GeV/$c$ by fully reconstructing the $B$ meson decays $B^{+}\to J/\psi K^{+}$ and $B^{0}\to J/\psi K^{*0}(892)$, where $J/\psi \to \mu^+\mu^-$ and $K^{*0} \to K^+ \pi^-$. A comparison is made to the theoretical QCD prediction calculated at next-to-leading order.

We report the first measurements of inclusive W and Z cross sections times leptonic branching ratios for pp collisions at square root[s]=1.96 TeV, based on their decays to electrons and muons. The data correspond to an integrated luminosity of 72 pb(-1) recorded with the CDF detector at the Fermilab Tevatron. We test e-mu universality in W decays, and we measure the ratio of leptonic W and Z rates from which the leptonic branching fraction B(W-->lnu) can be extracted as well as an indirect value for the total width of the W and the Cabibbo-Kobayashi-Maskawa matrix element, |V(cs)|.

We have used 106 pb^-1 of data collected with the Collider Detector at Fermilab to search for new particles decaying to dijets. We exclude at the 95% confidence level models containing the following new particles: axigluons and flavor universal colorons with mass between 200 and 980 GeV/c, excited quarks with mass between 80 and 570 GeV/c^2 and between 580 and 760 GeV/c^2, color octet technirhos with mass between 260 and 480 GeV/c^2, W' bosons with mass between 300 and 420 GeV/c^2, and E_6 diquarks with mass between 290 and 420 GeV/c^2.

A prompt photon cross section measurement from the Collider Detector at Fermilab experiment is presented. Detector and trigger upgrades, as well as 6 times the integrated luminosity compared with our previous publication, have contributed to a much more precise measurement and extended PT range. As before, QCD calculations agree qualitatively with the measured cross section, but the data has a steeper slope than the calculations.Received 26 July 1994DOI:https://doi.org/10.1103/PhysRevLett.73.2662©1994 American Physical Society

We report a measurement of the difference (Delta Acp) between time-integrated CP--violating asymmetries in D0-> K+ K- and D0-> pi+pi- decays reconstructed in the full data set of proton-antiproton collisions collected by the Collider Detector at Fermilab, corresponding to 9.7 fb-1 of integrated luminosity. The strong decay D*+->D0 pi+ is used to identify the charm meson at production as D0 or anti-D0. We measure Delta Acp = [-0.62 +- 0.21 (stat) +- 0.10 (syst)] %, which differs from zero by 2.7 Gaussian standard deviations.This result supports similar evidence for CP violation in charm-quark decays obtained in proton-proton collisions.

We report a measurement of the bottom-strange meson mixing phase \beta_s using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays in which the quark-flavor content of the bottom-strange meson is identified at production. This measurement uses the full data set of proton-antiproton collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity. We report confidence regions in the two-dimensional space of \beta_s and the B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2, -1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in agreement with the standard model expectation. Assuming the standard model value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +- 0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +- 0.009 (syst) ps, which are consistent and competitive with determinations by other experiments.

A search has been performed for B(s)(0) → μ+ μ- and B(0) → μ+ μ- decays using 7 fb(-1) of integrated luminosity collected by the CDF II detector at the Fermilab Tevatron collider. The observed number of B(0) candidates is consistent with background-only expectations and yields an upper limit on the branching fraction of B(B(0) → μ+ μ-) < 6.0 × 10(-9) at 95% confidence level. We observe an excess of B(s)(0) candidates. The probability that the background processes alone could produce such an excess or larger is 0.27%. The probability that the combination of background and the expected standard model rate of B(s)(0) → μ+ μ- could produce such an excess or larger is 1.9%. These data are used to determine B(B(s)(0)→ μ+ μ-) = (1.8(-0.9) (+1.1)) × 10(-8) and provide an upper limit of B(B(s)(0) → μ+ μ-) < 4.0 × 10(-8) at 95% confidence level.

We report on a measurement of CP-violating asymmetries (Acp) in the Cabibbo-suppressed D0 --> pi+ pi- and D0 --> K+K- decays reconstructed in a data sample corresponding to 5.9 fb-1 of integrated luminosity collected by the upgraded Collider Detector at Fermilab. We use the strong decay D*+ --> D0 pi+ to identify the flavor of the charmed meson at production and exploit CP-conserving strong c-cbar pair-production in p-pbar collisions. High-statistics samples of Cabibbo-favored D0 --> K- p+ decays with and without a D* tag are used to correct for instrumental effects and significantly reduce systematic uncertainties. We measure Acp(D0 --> pi+ pi-) = (+0.22 +- 0.24 (stat) +- 0.11 (syst))% and Acp(D 0 --> K+ K-) = (-0.24 +- 0.22 (stat) +- 0.09 (syst))%, in agreement with CP conservation. These are the most precise determinations from a single experiment to date. Under the assumption of negligible direct CP violation in D0 --> pi+ pi- and D0 --> K+K- decays, the results provide an upper limit to the CP-violating asymmetry in D0 mixing, |Acp^{ind}(D0)|< 0.13% at the 90% confidence level.

We present the results of a search for dark matter production in the monojet signature. We analyze a sample of Tevatron $p\overline{p}$ collisions at $\sqrt{s}=1.96\text{ }\text{ }\mathrm{TeV}$ corresponding to an integrated luminosity of $6.7\text{ }\text{ }\mathrm{f}{\mathrm{b}}^{\ensuremath{-}1}$ recorded by the CDF II detector. In events with large missing transverse energy and one energetic jet, we find good agreement between the standard model prediction and the observed data. We set 90% confidence level upper limits on the dark matter production rate. The limits are translated into bounds on nucleon-dark matter scattering rates which are competitive with current direct detection bounds on spin-independent interaction below a dark matter candidate mass of $5\text{ }\text{ }\mathrm{GeV}/{c}^{2}$, and on spin-dependent interactions up to masses of $200\text{ }\text{ }\mathrm{GeV}/{c}^{2}$.

Using the full CDF Run II data sample, we report evidence for a new resonance, which we refer to as $B(5970)$, found simultaneously in the ${B}^{0}{\ensuremath{\pi}}^{+}$ and ${B}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ mass distributions with a significance of 4.4 standard deviations. We further report the first study of resonances consistent with orbitally excited ${B}^{+}$ mesons and an updated measurement of the properties of orbitally excited ${B}^{0}$ and ${B}_{s}^{0}$ mesons. We measure the masses and widths of all states, as well as the relative production rates of the ${B}_{1}$, ${B}_{2}^{*}$, and $B(5970)$ states and the branching fraction of the ${B}_{s2}^{*0}$ state to either ${B}^{*+}{K}^{\ensuremath{-}}$ and ${B}^{+}{K}^{\ensuremath{-}}$. Furthermore, we measure the production rates of the orbitally excited ${B}^{0,+}$ states relative to the ${B}^{0,+}$ ground state. The masses of the new $B(5970)$ resonances are $5978\ifmmode\pm\else\textpm\fi{}5(\text{stat})\ifmmode\pm\else\textpm\fi{}12(\text{syst})\text{ }\text{ }\mathrm{MeV}/{c}^{2}$ for the neutral state and $5961\ifmmode\pm\else\textpm\fi{}5(\text{stat})\ifmmode\pm\else\textpm\fi{}12(\text{syst})\text{ }\text{ }\mathrm{MeV}/{c}^{2}$ for the charged state, assuming that the resonance decays into $B\ensuremath{\pi}$ final states. The properties of the orbitally excited and the new $B(5970{)}^{0,+}$ states are compatible with isospin symmetry.

The observation of the [Formula: see text] structure in [Formula: see text] decays produced in [Formula: see text] collisions at [Formula: see text] TeV is reported with a statistical significance greater than 5 standard deviations. A fit to the [Formula: see text] mass spectrum is performed assuming the presence of a Breit–Wigner resonance. The fit yields a signal of [Formula: see text] resonance events, and resonance mass and width of [Formula: see text] and [Formula: see text], respectively. The parameters of this resonance-like structure are consistent with values reported from an earlier CDF analysis.

We report results from a study of events with a leading antiproton of beam momentum fraction 0.905<x(F)<0.965 and 4-momentum transfer squared |t|<3 GeV2 produced in &pmacr;p collisions at sqrt[s] = 1800 GeV at the Fermilab Tevatron collider. Approximately 2% of the events contain two jets of transverse energy E(jet)(T)>7 GeV. Using the dijet events, we evaluate the diffractive structure function of the antiproton and compare it with expectations based on results obtained in diffractive deep inelastic scattering experiments at the DESY ep collider HERA.

A strong signal for double parton scattering (DP) is observed in a $16\mathrm{pb}{}^{\ensuremath{-}1}$ sample of $\overline{p}p\ensuremath{\rightarrow}\ensuremath{\gamma}+3\mathrm{jets}+X$ data from the CDF experiment at the Fermilab Tevatron. The process-independent DP parameter, ${\ensuremath{\sigma}}_{\mathrm{eff}}$, is obtained without reference to theoretical calculations by comparing observed DP events to events with hard scatterings at separate $\overline{p}p$ collisions. The result, ${\ensuremath{\sigma}}_{\mathrm{eff}}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}(14.5\ifmmode\pm\else\textpm\fi{}{1.7}_{\ensuremath{-}2.3}^{+1.7})\mathrm{mb}$, represents a significant improvement over previous measurements. For the first time, the Feynman $x$ dependence of the ${\ensuremath{\sigma}}_{\mathrm{eff}}$ parameter is investigated, and no dependence is seen.

This paper reports an updated measurement of the Standard Model CP violation parameter $\sin2\beta$ using the CDF Detector at Fermilab. The entire Run I data sample of 110 pb$^{-1}$ of proton antiproton collisions at $\sqrt{s}=1.8 TeV$ is used to identify a signal sample of $\sim 400$ $B \to J/\psi K^0_S$ events, where $J/\psi \to \mu^+\mu^-$ and $K_S^0 \to \pi^+\pi^-$. The flavor of the neutral B meson is identified at the time of production by combining information from three tagging algorithms: a same-side tag, a jet-charge tag, and a soft-lepton tag. A maximum likelihood fitting method is used to determine $\sin2\beta = 0.79 {+0.41\atop-0.44}$(stat+syst). This value of $\sin 2 \beta$ is consistent with the Standard Model prediction, based upon existing measurements, of a large positive CP violating asymmetry in this decay mode.

This Letter describes a direct search for charged Higgs boson production in $p\overline{p}$ collisions at $\sqrt{s}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1.8\mathrm{TeV}$ recorded by the Collider Detector at Fermilab. Two-Higgs-double extensions to the standard model predict the existence of charged Higgs bosons $({H}^{\ifmmode\pm\else\textpm\fi{}})$. In such models, the branching fraction for top quarks $B(t\ensuremath{\rightarrow}{H}^{+}b\ensuremath{\rightarrow}{\ensuremath{\tau}}^{+}\ensuremath{\nu}b)$ can be large. This search uses the hadronic decays of the tau lepton in this channel to significantly extend previous limits on ${H}^{\ifmmode\pm\else\textpm\fi{}}$ production.

This paper presents a measurement of the mass of the W boson using data collected with the CDF detector during the 1992–1993 collider run at the Fermilab Tevatron. A fit to the transverse mass spectrum of a sample of 3268 W→μν events recorded in an integrated luminosity of 19.7 pb−1 gives MμW=80.310±0.205 (stat)±0.130 (syst) GeV/c2. A fit to the transverse mass spectrum of a sample of 5718 W→eν events recorded in 18.2 pb−1 gives MeW=80.490±0.145 (stat)±0.175 (syst) GeV/c2. Combining the muon and electron results, accounting for correlated uncertainties, yields MW=80.410±0.180 GeV/c2.Received 7 March 1995DOI:https://doi.org/10.1103/PhysRevD.52.4784©1995 American Physical Society

For comparison of inclusive jet cross sections measured at hadron-hadron colliders to next-to-leading order (NLO) parton-level calculations, the energy deposited in the jet cone by spectator parton interactions must first be subtracted. The assumption made at the Tevatron is that the spectator parton interaction energy is similar to the ambient level measured in minimum bias events. In this paper, we test this assumption by measuring the ambient charged track momentum in events containing large transverse energy jets at $\sqrt{s}=1800$ GeV and $\sqrt{s}=630$ GeV and comparing this ambient momentum with that observed both in minimum bias events and with that predicted by two Monte Carlo models. Two cones in $\eta$--$\phi$ space are defined, at the same pseudo-rapidity, $\eta$, as the jet with the highest transverse energy ($E_T^{(1)}$), and at $\pm 90^o$ in the azimuthal direction, $\phi$. The total charged track momentum inside each of the two cones is measured. The minimum momentum in the two cones is almost independent of $E_T^{(1)}$ and is similar to the momentum observed in minimum bias events, whereas the maximum momentum increases roughly linearly with the jet $E_T^{(1)}$ over most of the measured range. This study will help improve the precision of comparisons of jet cross section data and NLO perturbative QCD predictions. %this is new The distribution of the sum of the track momenta in the two cones is also examined for five different $E_T^{(1)}$ bins. The HERWIG and PYTHIA Monte Carlos are reasonably successful in describing the data, but neither can describe completely all of the event properties.

Purpose To determine the implications of the use of the Anisotropic Analytical Algorithm (AAA) for the production and dosimetric verification of IMRT plans for treatments of the prostate, parotid, nasopharynx and lung. Methods 72 IMRT treatment plans produced using the Pencil Beam Convolution (PBC) algorithm were recalculated using the AAA and the dose distributions compared. Twenty-four of the plans were delivered to inhomogeneous phantoms and verification measurements made using a pinpoint ionisation chamber. The agreement between the AAA and measurement was determined. Results Small differences were seen in the prostate plans, with the AAA predicting slightly lower minimum PTV doses. In the parotid plans, there were small increases in the lens and contralateral parotid doses while the nasopharyngeal plans revealed a reduction in the volume of the PTV covered by the 95% isodose (the V95%) when the AAA was used. Large changes were seen in the lung plans, the AAA predicting reductions in the minimum PTV dose and large reductions in the V95%. The AAA also predicted small increases in the mean dose to the normal lung and the V20. In the verification measurements, all AAA calculations were within 3% or 3.5 mm distance to agreement of the measured doses. Conclusions The AAA should be used in preference to the PBC algorithm for treatments involving low density tissue but this may necessitate re-evaluation of plan acceptability criteria. Improvements to the Multi-Resolution Dose Calculation algorithm used in the inverse planning are required to reduce the convergence error in the presence of lung tissue. There was excellent agreement between the AAA and verification measurements for all sites.

Data collected in run II of the Fermilab Tevatron are searched for indications of new electroweak-scale physics. Rather than focusing on particular new physics scenarios, CDF data are analyzed for discrepancies with the standard model prediction. A model-independent approach (Vista) considers gross features of the data, and is sensitive to new large cross-section physics. Further sensitivity to new physics is provided by two additional algorithms: a Bump Hunter searches invariant mass distributions for ``bumps'' that could indicate resonant production of new particles, and the Sleuth procedure scans for data excesses at large summed transverse momentum. This combined global search for new physics in $2.0\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of $p\overline{p}$ collisions at $\sqrt{s}=1.96\text{ }\text{ }\mathrm{TeV}$ reveals no indication of physics beyond the standard model.

We report the most sensitive direct search for pair production of fourth-generation bottomlike chiral quarks (b') each decaying promptly to tW. We search for an excess of events with an electron or muon, at least five jets (one identified as due to a b or c quark), and an imbalance of transverse momentum by using data from pp collisions collected by the CDF II detector at Fermilab with an integrated luminosity of 4.8 fb(-1). We observe events consistent with background expectation, calculate upper limits on the b' pair-production cross section (σ(bb')) ≲30 fb for m(b') > 375 GeV/c2), and exclude m(b') < 372 GeV/c2 at 95% confidence level assuming a 100% branching ratio of b' to tW.

We report a measurement of the ratio of the tt to Z/γ{*} production cross sections in sqrt[s]=1.96 TeV pp collisions using data corresponding to an integrated luminosity of up to 4.6 fb{-1}, collected by the CDF II detector. The tt cross section ratio is measured using two complementary methods, a b-jet tagging measurement and a topological approach. By multiplying the ratios by the well-known theoretical Z/γ{*}→ll cross section predicted by the standard model, the extracted tt cross sections are effectively insensitive to the uncertainty on luminosity. A best linear unbiased estimate is used to combine both measurements with the result σ{tt}=7.70±0.52 pb, for a top-quark mass of 172.5 GeV/c{2}.

We study the underlying event in proton-antiproton collisions by examining the behavior of charged particles produced in association with a large transverse momentum jet ($\ensuremath{\sim}2.2\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$) or with a Drell-Yan lepton pair ($\ensuremath{\sim}2.7\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$) in the $Z$-boson mass region [$70&lt;M(\mathrm{\text{pair}})&lt;110\text{ }\text{ }\mathrm{GeV}/{c}^{2}$] as measured by CDF at 1.96 TeV center-of-mass energy. We use the direction of the lepton pair or the leading jet in each event to define regions of $\ensuremath{\eta}\mathrm{\text{\ensuremath{-}}}\ensuremath{\phi}$ space that are sensitive to the modeling of the underlying event. The data are corrected to the particle level to remove detector effects and are then compared with several QCD Monte Carlo models.

We present a precision measurement of the top-quark mass using the full sample of Tevatron $\sqrt{s}=1.96$ TeV proton-antiproton collisions collected by the CDF II detector, corresponding to an integrated luminosity of 8.7 $fb^{-1}$. Using a sample of $t\bar{t}$ candidate events decaying into the lepton+jets channel, we obtain distributions of the top-quark masses and the invariant mass of two jets from the $W$ boson decays from data. We then compare these distributions to templates derived from signal and background samples to extract the top-quark mass and the energy scale of the calorimeter jets with {\it in situ} calibration. The likelihood fit of the templates from signal and background events to the data yields the single most-precise measurement of the top-quark mass, $\mtop = 172.85 $\pm$ 0.71 (stat) $\pm$ 0.85 (syst) GeV/c^{2}.$

This Letter describes the current most precise measurement of the $W$ boson pair production cross section and most sensitive test of anomalous $WW\ensuremath{\gamma}$ and $WWZ$ couplings in $p\overline{p}$ collisions at a center-of-mass energy of 1.96 TeV. The $WW$ candidates are reconstructed from decays containing two charged leptons and two neutrinos. Using data collected by the CDF II detector from $3.6\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of integrated luminosity, a total of 654 candidate events are observed with an expected background of $320\ifmmode\pm\else\textpm\fi{}47$ events. The measured cross section is $\ensuremath{\sigma}(p\overline{p}\ensuremath{\rightarrow}{W}^{+}{W}^{\ensuremath{-}}+X)=12.1\ifmmode\pm\else\textpm\fi{}0.9(\mathrm{stat}{)}_{\ensuremath{-}1.4}^{+1.6}(\mathrm{syst})\text{ }\text{ }\mathrm{pb}$, which is in good agreement with the standard model prediction. The same data sample is used to place constraints on anomalous $WW\ensuremath{\gamma}$ and $WWZ$ couplings.

We report measurements of direct CP-violating asymmetries in charmless decays of neutral bottom hadrons to pairs of charged hadrons with the upgraded Collider Detector at the Fermilab Tevatron. Using a data sample corresponding to 1 fb-1 of integrated luminosity, we obtain the first measurements of direct CP violation in bottom strange mesons, A_CP(BsKpi) = +0.39 +- 0.15 stat +- 0.08 syst, and bottom baryons, A_CP(Lb->ppi) = +0.03 +- 0.17 stat +- 0.05 syst and A_CP(Lb->pK) = +0.37 +- 0.17 +- 0.03 syst. In addition, we measure CP violation in Bd-->Kpi decays with 3.5sigma significance, A_CP(B->Kpi) = -0.086 +- 0.023 stat +- 0.009 syst, in agreement with the current world average. Measurements of branching fractions of Bs-->K+K- and B0-->pi+pi- decays are also updated.

An algorithm for reconstruction of the Higgs mass in H → ττ decays is presented. The algorithm computes for each event a likelihood function P(Mττ) which quantifies the level of compatibility of a Higgs mass hypothesis Mττ with measured momenta of the visible tau decay products plus the missing transverse energy reconstructed in the event. The algorithm is used in the CMS H → ττ analysis, where it is found to improve the sensitivity to discover the Standard Model Higgs boson in this decay channel by about 30%.

Red clover cultivation made significant contributions to soil fertility prior to the introduction of mineral nitrogen fertilizers. Its modern usage lies primarily in forage production, but reintegration into arable systems can enhance sustainability and preserve environmental integrity. Here we review red clovers nitrogen (N) contribution to subsequent crops, its capacity to fix N, and how this N is transferred to subsequent crops. The senescence of the root system following cultivation also contributes to soil organic matter, providing a suite of ecosystem services which are also reviewed. Potential contributions to allelopathic weed control and how this may be utilized to improve weed control is also discussed. Red clover varieties are diverse and can be split into categories of early/late flowering, erect/prostrate and diploid/tetraploid. This use of this diversity to different ends and purposes in fertility-building and the role of plant breeding in optimizing use of genetic resources is reviewed. Management strategies are also diverse; red clover can be grown in monoculture or with companion grasses, it can be harvested for forage or green manured (which can include or omit herbicides) and the consequence of this for soil fertility is discussed. High protein forage production is also a key benefit of red clover cultivation and the economic incentive this may provide to farmers is also reviewed.

We present a measurement of the top quark mass using a sample of tt¯ decays into an electron or a muon, a neutrino, and four jets. The data were collected in pp¯ collisions at s=1.8TeV with the Collider Detector at Fermilab and correspond to an integrated luminosity of 109pb−1. We measure the top quark mass to be 175.9±4.8(stat)±4.9(syst)GeV/c2.Received 30 September 1997DOI:https://doi.org/10.1103/PhysRevLett.80.2767©1998 American Physical Society

We report the first observation of diffractively produced W bosons. In a sample of W -> e nu events produced in p-barp collisions at sqrt{s}=1.8 TeV, we find an excess of events with a forward rapidity gap, which is attributed to diffraction. The probability that this excess is consistent with non-diffractive production is 1.1 10^{-4} (3.8 sigma). The relatively low fraction of W+Jet events observed within this excess implies that mainly quarks from the pomeron, which mediates diffraction, participate in W production. The diffractive to non-diffractive W production ratio is found to be R_W=(1.15 +/- 0.55)%.

We present an analysis of dilepton events originating from top-antitop production in proton-antiproton collisions at sqrt{s}=1.8 TeV at the Fermilab Tevatron Collider. The sample corresponds to an integrated luminosity of 109+-7 pb^{-1}. We observe 9 candidate events, with an estimated background of 2.4+-0.5 events. We determine the mass of the top quark to be M_top = 161+-17(stat.)+-10(syst.) GeV/c^2. In addition we measure a top-antitop production cross section of 8.2+4.4-3.4 pb (where M_top = 175 GeV/c^2 has been assumed for the acceptance estimate).

We report on measurements of the $\ensuremath{\Upsilon}(1S)$, $\ensuremath{\Upsilon}(2S)$, and $\ensuremath{\Upsilon}(3S)$ differential, ${(\frac{{d}^{2}\ensuremath{\sigma}}{d{P}_{t}\mathrm{dy}})}_{y=0}$, and integrated cross sections in $p\overline{p}$ collisions at $\sqrt{s}=1.8$ TeV using a sample of 16.6 \ifmmode\pm\else\textpm\fi{} 0.6 ${\mathrm{pb}}^{\ensuremath{-}1}$ collected by the Collider Detector at Fermilab. The three resonances were reconstructed through the decay $\ensuremath{\Upsilon}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$. Comparison is made to a leading order QCD prediction.

The present status of CT simulation (CT sim) hardware, software and practice is reviewed, particularly with regard to the changes that have taken place over the last 5 years. The latest technology is discussed together with some recently developed techniques. The article concludes with a discussion of virtual simulation vs physical (conventional) simulation; in particular there is a review of the changes that have been made to the "Disadvantages table" presented by Conway and Robinson [1], which now make CT sim an attractive system for any radiotherapy department.

We have used $106{\mathrm{pb}}^{\ensuremath{-}1}$ of data collected in $p\overline{p}$ collisions at $\sqrt{s}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1.8\mathrm{TeV}$ by the Collider Detector at Fermilab to measure jet angular distributions in events with two jets in the final state. The angular distributions agree with next to leading order predictions of QCD in all dijet invariant mass regions. The data exclude at 95% CL a model of quark substructure in which only up and down quarks are composite and the contact interaction scale is ${\ensuremath{\Lambda}}_{\mathrm{ud}}^{+}\ensuremath{\le}1.6\mathrm{TeV}$ or ${\ensuremath{\Lambda}}_{\mathrm{ud}}^{\ensuremath{-}}\ensuremath{\le}1.4\mathrm{TeV}$. For a model in which all quarks are composite the excluded regions are ${\ensuremath{\Lambda}}^{+}\ensuremath{\le}1.8\mathrm{TeV}$ and ${\ensuremath{\Lambda}}^{\ensuremath{-}}\ensuremath{\le}1.6\mathrm{TeV}$.

To compare external beam radiotherapy techniques for parotid gland tumours using conventional radiotherapy (RT), three-dimensional conformal radiotherapy (3DCRT), and intensity-modulated radiotherapy (IMRT). To optimise the IMRT techniques, and to produce an IMRT class solution.The planning target volume (PTV), contra-lateral parotid gland, oral cavity, brain-stem, brain and cochlea were outlined on CT planning scans of six patients with parotid gland tumours. Optimised conventional RT and 3DCRT plans were created and compared with inverse-planned IMRT dose distributions using dose-volume histograms. The aim was to reduce the radiation dose to organs at risk and improve the PTV dose distribution. A beam-direction optimisation algorithm was used to improve the dose distribution of the IMRT plans, and a class solution for parotid gland IMRT was investigated.3DCRT plans produced an equivalent PTV irradiation and reduced the dose to the cochlea, oral cavity, brain, and other normal tissues compared with conventional RT. IMRT further reduced the radiation dose to the cochlea and oral cavity compared with 3DCRT. For nine- and seven-field IMRT techniques, there was an increase in low-dose radiation to non-target tissue and the contra-lateral parotid gland. IMRT plans produced using three to five optimised intensity-modulated beam directions maintained the advantages of the more complex IMRT plans, and reduced the contra-lateral parotid gland dose to acceptable levels. Three- and four-field non-coplanar beam arrangements increased the volume of brain irradiated, and increased PTV dose inhomogeneity. A four-field class solution consisting of paired ipsilateral coplanar anterior and posterior oblique beams (15, 45, 145 and 170 degrees from the anterior plane) was developed which maintained the benefits without the complexity of individual patient optimisation.For patients with parotid gland tumours, reduction in the radiation dose to critical normal tissues was demonstrated with 3DCRT compared with conventional RT. IMRT produced a further reduction in the dose to the cochlea and oral cavity. With nine and seven fields, the dose to the contra-lateral parotid gland was increased, but this was avoided by optimisation of the beam directions. The benefits of IMRT were maintained with three or four fields when the beam angles were optimised, but were also achieved using a four-field class solution. Clinical trials are required to confirm the clinical benefits of these improved dose distributions.

We have performed a search for gluinos (g) and scalar quarks (q) in a data sample of 84 pb(-1) of pp collisions at square root[s] = 1.8 TeV, recorded by the Collider Detector at Fermilab. We investigate the final state of large missing transverse energy and three or more jets, a characteristic signature in R-parity-conserving supersymmetric models. The analysis has been performed "blind," in that the inspection of the signal region is made only after the predictions from standard model backgrounds have been calculated. Comparing the data with predictions of constrained supersymmetric models, we exclude gluino masses below 195 GeV/c2 (95% C.L.), independent of the squark mass. For the case m(q) approximately m(g), gluino masses below 300 GeV/c2 are excluded.

We describe a measurement of the charge asymmetry of leptons from W boson decays in the rapidity range 0 < |y l | < 2.5 using W → eν, µν events from 110 ± 7 pb -1 of data collected by the CDF detector during 1992-95.The asymmetry data constrain the ratio of d and u quark momentum distributions in the proton over the x range of 0.006 to 0.34 at Q 2 ≈ M 2 W .The asymmetry predictions that use parton distribution functions obtained from previously published CDF data in the central

Restitutions and reparations origins of the Claims Conference European Jewry after the Holocaust reparations and the organizations principles of allocation and the cultural programme the challenge of reconstruction commemorating the Holocaust beyond welfare.

We report the observation and measurement of the rate of diffractive dijet production at the Fermilab Tevatron $\overline{p}p$ collider at $\sqrt{s}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1.8\mathrm{TeV}$. In events with two jets of ${E}_{T}&gt;20\mathrm{GeV}$, $1.8&lt;|\ensuremath{\eta}|&lt;3.5$, and ${\ensuremath{\eta}}_{1}{\ensuremath{\eta}}_{2}&gt;0$, we find that the diffractive to nondiffractive production ratio is ${R}_{\mathrm{JJ}}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}[0.75\ifmmode\pm\else\textpm\fi{}0.05(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.09(\mathrm{syst})]%$. By comparing this result, in combination with our measured rate for diffractive $W$ boson production reported previously, with predictions based on a hard partonic pomeron structure, we determine the pomeron gluon fraction to be ${f}_{g}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0.7\ifmmode\pm\else\textpm\fi{}0.2$.

The dilepton mass spectrum in $p\overline{p}\ensuremath{\rightarrow}{l}^{+}{l}^{\ensuremath{-}}+X$ interactions is studied using dielectrons (ee) and dimuons (\ensuremath{\mu}\ensuremath{\mu}) in $110{\mathrm{pb}}^{\ensuremath{-}1}$ of data collected with the Collider Detector at Fermilab. The data are consistent with standard model predictions. The mass spectrum, being a probe for new physics, is examined for new interactions of quarks and leptons from a common composite structure. Assuming a contact interaction with the conventional coupling ${g}_{0}^{2}/4\ensuremath{\pi}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1$, limits on chiral quark-electron and quark-muon compositeness scales in the range of 2.5 to 4.2 TeV are obtained.

To investigate the accuracy of photon dose calculations performed by the Anisotropic Analytical Algorithm, in homogeneous and inhomogeneous media and in simulated treatment plans.Predicted dose distributions were compared with ionisation chamber and film measurements for a series of increasingly complex situations. Initially, simple and complex fields in a homogeneous medium were studied. The effect of inhomogeneities was investigated using a range of phantoms constructed of water, bone and lung substitute materials. Simulated treatment plans were then produced using a semi-anthropomorphic phantom and the delivered doses compared to the doses predicted by the Anisotropic Analytical Algorithm.In a homogeneous medium, agreement was found to be within 2% dose or 2mm dta in most instances. In the presence of heterogeneities, agreement was generally to within 2.5%. The simulated treatment plan measurements agreed to within 2.5% or 2mm.The accuracy of the algorithm was found to be satisfactory at 6 and 10MV both in homogeneous and inhomogeneous situations and in the simulated treatment plans. The algorithm was more accurate than the Pencil Beam Convolution model, particularly in the presence of low density heterogeneities.

For the hyperthermia treatment of human cancers considerable advantage would be gained from the ability to map temperatures deep within the body by non-invasive methods. This could be achieved by the measurement of some parameter that is sensitive to temperature change but insensitive to all other influences. Such a system must also be capable of operating in strong EM fields and be easily accommodated within all hyperthermia treatment configurations. A new thermal imaging technique by mapping electrical conductivity changes with temperature has been investigated. Temperature changes could, in principle, be deduced from this measured data if the temperature coefficient of conductivity for tissue (typically 2% per degree C) is known. Experimental studies have been performed with a 16-electrode system using an agar phantom (conductivity 2.0 S m-1). Heating of a small area of the surface is achieved using a 2 cm diameter microwave diathermy applicator. A time series of images readily shows the distribution of thermal changes and suggests a temperature resolution better than 1 degree C. In vivo experiments were performed by heating the scapula region of a volunteer while monitoring the induced temperature change with the same electrode configuration affixed to the skin surface. These results show a greater degree of image artefacts compared with the phantom results, possibly caused by a combination of body movement, blood flow effects and electrode contact degradation. These initial experiments have demonstrated the feasibility of non-invasive thermal mapping using electrical impedance imaging. Phantom studies have shown the possibility of displaying the thermal distribution induced by microwave applicators for both profile and depth planes in tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

We reconstruct the rare decays B(+)→K(+)μ(+0μ(-0, B90)→K*(892)(0)μ(+)μ(-), and B(s)(0)→ϕ(1020)μ(+)μ(-) in a data sample corresponding to 4.4 fb(-1) collected in pp collisions at √[s]=1.96 TeV by the CDF II detector at the Tevatron Collider. Using 121±16 B(+)→K(+)μ(+)μ(-) and 101±12 B(0)→K(*0)μ(+)μ(-) decays we report the branching ratios. In addition, we report the differential branching ratio and the muon forward-backward asymmetry in the B(+) and B(0) decay modes, and the K(*0) longitudinal polarization fraction in the B(0) decay mode with respect to the squared dimuon mass. These are consistent with the predictions, and most recent determinations from other experiments and of comparable accuracy. We also report the first observation of the B(s)(0)→ϕμ(+)μ(-) decay and measure its branching ratio BR(B(s)(0)→ϕμ(+)μ(-))=[1.44±0.33±0.46]×10(-6) using 27±6 signal events. This is currently the most rare B(s)(0) decay observed.

We report measurements of the resonance properties of ${\ensuremath{\Lambda}}_{c}(2595{)}^{+}$ and ${\ensuremath{\Lambda}}_{c}(2625{)}^{+}$ baryons in their decays to ${\ensuremath{\Lambda}}_{c}^{+}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ as well as ${\ensuremath{\Sigma}}_{c}(2455{)}^{++,0}$ and ${\ensuremath{\Sigma}}_{c}(2520{)}^{++,0}$ baryons in their decays to ${\ensuremath{\Lambda}}_{c}^{+}{\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}$ final states. These measurements are performed using data corresponding to $5.2\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of integrated luminosity from $p\overline{p}$ collisions at $\sqrt{s}=1.96\text{ }\text{ }\mathrm{TeV}$, collected with the CDF II detector at the Fermilab Tevatron. Exploiting the largest available charmed baryon sample, we measure masses and decay widths with uncertainties comparable to the world averages for ${\ensuremath{\Sigma}}_{c}$ states, and significantly smaller uncertainties than the world averages for excited ${\ensuremath{\Lambda}}_{c}^{+}$ states.

The transverse momentum cross section of ${e}^{+}{e}^{\ensuremath{-}}$ pairs in the $Z$-boson mass region of $66--116\text{ }\text{ }\mathrm{GeV}/{c}^{2}$ is precisely measured using Run II data corresponding to $2.1\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of integrated luminosity recorded by the Collider Detector at Fermilab. The cross section is compared with two quantum chromodynamic calculations. One is a fixed-order perturbative calculation at $\mathcal{O}({\ensuremath{\alpha}}_{s}^{2})$, and the other combines perturbative predictions at high transverse momentum with the gluon resummation formalism at low transverse momentum. Comparisons of the measurement with calculations show reasonable agreement. The measurement is of sufficient precision to allow refinements in the understanding of the transverse momentum distribution.

The angular distributions of muons from Υ(1S,2S,3S) → μ+ μ- decays are measured using data from pp collisions at sqrt[s] = 1.96 TeV corresponding to an integrated luminosity of 6.7 fb(-1) and collected with the CDF II detector at the Fermilab Tevatron. This analysis is the first to report the full angular distributions as functions of transverse momentum p(T) for Υ mesons in both the Collins-Soper and s-channel helicity frames. This is also the first measurement of the spin alignment of Υ(3S) mesons. Within the kinematic range of Υ rapidity |y|<0.6 and p(T) up to 40 GeV/c, the angular distributions are found to be nearly isotropic.

The $t\overline{t}$ spin correlation at production is a fundamental prediction of QCD and a potentially incisive test of new physics coupled to top quarks. We measure the $t\overline{t}$ spin state in $p\overline{p}$ collisions at $\sqrt{s}=1.96\text{ }\text{ }\mathrm{TeV}$ using 1001 candidate events in the lepton plus jets decay channel reconstructed in the CDF II detector. In the helicity basis, for a top-quark mass of $172.5\text{ }\text{ }\mathrm{GeV}/{c}^{2}$, we find a spin correlation coefficient $\ensuremath{\kappa}=0.60\ifmmode\pm\else\textpm\fi{}0.50\text{ }\text{ }(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.16\text{ }\text{ }(\mathrm{syst})$, consistent with the QCD prediction, $\ensuremath{\kappa}\ensuremath{\approx}0.40$.

We report on the first measurement of the angular distributions of final state electrons in $p\bar{p}\to \gamma^{*}/Z\to e^{+}e^{-}+X$ events produced in the $Z$ boson mass region at $\sqrt{s}=1.96$ TeV. The data sample collected by the CDF II detector for this result corresponds to 2.1 fb$^{-1}$ of integrated luminosity. The angular distributions are studied as a function of the transverse momentum of the electron-positron pair and show good agreement with the Lam-Tung relation, consistent with a spin-1 description of the gluon, and demonstrate that at high values of the transverse momentum, $Z$ bosons are produced via quark anti-quark annihilation and quark-gluon Compton processes.

Within the existing literature, the role of experience of risk on attitudinal and behavioural risk response has been relatively neglected. Recent research that draws on the psychological distance of climate change as a concept notes the importance of local, significant experience as a driver for encouraging appropriate response. The experience of flooding was used as the stimulus in this paper, and emphasis placed on whether direct and/or indirect experience of flood risk is associated with different responses to climate change risk. In order to explore the relationship between climate change risk experience and response in the form of on-farm mitigation and adaptation, this paper draws on a case study of farmers in England, many of whom have experienced flooding. Results from a quantitative survey undertaken with 200 farmers in Gloucestershire, England are discussed. Statistical analysis found experience of flooding to be significantly associated with a heightened concern for climate change. Although also finding an association between experience and behavioural response, the sample were most likely to be taking adaptive behaviour as part of normal practice, with factors such as lack of overall concern for climate change risk and absence of information and advice likely to be the main barriers to action. Risk communication needs to further emphasise the connection between climate change and extreme weather events to allow for farmers to perceive climate change as a relevant and locally salient phenomenon, and subsequent tailored information and advice should be offered to clearly illustrate the best means of on-farm response. Where possible, emphasis must be placed on actions that also enable adaptation to other, more immediate risks which farmers in this study more readily exhibited concern for, such as market volatility.

Purpose: Empirical evidence suggests that climate-smart agriculture (CSA) practices will promote resilience against climate change. We explored location-specific CSA practices and strategies for adoption in two communities (Zango and Kofa) in the North-Western Nigerian drylands.Design/methodology/approach: Mixed methods design was employed with thirty smallholders per community selected from a baseline study of 220 smallholders from the two study communities. Smallholders were engaged in a farmer participatory learning and action (PLA) on CSA adoption for resilience. Impacts of PLA were evaluated six months post-implementation and barriers for adoption explored.Findings: Pre- and post-PLA training indicated a change in confidence to adopt some CSA practices. Both communities showed greater confidence (p < .05) related to solving climate-related problems and the use of fertiliser. Communities differed in relation to other factors: Kofa exhibited improved confidence (71.4%) in solving water challenges while Zango showed greater confidence (76%) in relation to solving environmental problems. We found gender-responsive CSA promote women participation in farming.Practical implications: A deep understanding of the underlying reasoning behind non-adoption of CSA practices could support future climate resilience policies, and the lead-farmer extension model could reduce extension agent-farmer ratio.Theoretical implications: Identification of climate-smart agriculture practices and their adoption confirms the benefit of participatory learning for transformation, in this case, empowerment of smallholders, including women, to adapt to climate change in a wider sub-Saharan Africa context.Originality/value: This study explores PLA application in supporting the uptake of CSA practices for resilience and advancement of lead-farmer extension for reducing extension agent-farmer ratio.

We present a new measurement of the top quark mass in $t\overline{t}$ events in which both $W$ bosons from top quarks decay into leptons $(e\ensuremath{\nu},\ensuremath{\mu}\ensuremath{\nu})$. We use events collected by the CDF experiment from $p\overline{p}$ collisions at $\sqrt{s}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1.8\mathrm{TeV}$ at the Tevatron collider. We measure a top quark mass of $167.4\ifmmode\pm\else\textpm\fi{}10.3(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}4.8(\mathrm{syst})\phantom{\rule{0ex}{0ex}}\mathrm{GeV}{/c}^{2}$ from a sample of eight events. We combine this result with previous CDF measurements in other decay channels to obtain a final mass value of $176.0\ifmmode\pm\else\textpm\fi{}6.5\mathrm{GeV}{/c}^{2}$.

We present a measurement of the W boson mass using data collected with the CDF detector during the 1994-95 collider run at the Fermilab Tevatron. A fit to the transverse mass spectrum of a sample of 30,115 W -&gt; enu events recorded in an integrated luminosity of 84 pb^(-1) gives a mass Mw = 80.473 +- 0.065(stat.) +- 0.092(syst.) GeV/c^2. A fit to the transverse mass spectrum of a sample of 14,740 W -&gt; munu events from 80 pb^(-1) gives a mass Mw = 80.465 +- 0.100(stat.) +- 0.103(syst.) GeV/c^2. The dominant contributions to the systematic uncertainties are the uncertainties in the electron energy scale and the muon momentum scale, 0.075 GeV/c^2 and 0.085 GeV/c^2, respectively. The combined value for the electron and muon channel is Mw = 80.470 +- 0.089 GeV/c^2. When combined with previously published CDF measurements, we obtain Mw = 80.433 +- 0.079 GeV/c^2.

We present measurements of correlated b¯b cross sections, μ−μ correlations, the average B0¯B0 mixing parameter ¯χ, and a limit on the CP-violating parameter εB. For these measurements, we use muon pairs from b¯b double semileptonic decays. The data used in this analysis were taken with the Collider Detector at Fermilab and represent an integrated luminosity of 17.4±0.6 pb−1. The results concerning b¯b production correlations are compared to predictions of next-to-leading order QCD computations.Received 12 August 1996DOI:https://doi.org/10.1103/PhysRevD.55.2546©1997 American Physical Society

We report a measurement of the ttbar production cross section using dilepton events with jets and missing transverse energy in ppbar collisions at a center-of-mass energy of 1.96 TeV. Using a 197 +/- 12 pb-1 data sample recorded by the upgraded Collider Detector at Fermilab, we use two complementary techniques to select candidate events. We compare the number of observed events and selected kinematical distributions with the predictions of the Standard Model and find good agreement. The combined result of the two techniques yields a ttbar production cross section of 7.0 +2.4/-2.1(stat.) +1.6/-1.1(syst.) +/- 0.4(lum.) pb.

We report a new measurement of dijet production by color-singlet exchange in $p\overline{p}$ collisions at $\sqrt{s}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1.8\mathrm{TeV}$ at the Fermilab Tevatron. In a sample of events with two jets of transverse energy ${E}_{T}^{\mathrm{jet}}&gt;20\mathrm{GeV}$, pseudorapidity in the range $1.8&lt;|{\ensuremath{\eta}}^{\mathrm{jet}}|&lt;3.5$, and ${\ensuremath{\eta}}_{1}{\ensuremath{\eta}}_{2}&lt;0$, we find that a fraction $R\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}[1.13\ifmmode\pm\else\textpm\fi{}0.12(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.11(\mathrm{syst})]%$ has a pseudorapidity gap within $|\ensuremath{\eta}|&lt;1$ between the jets that can be attributed to color-singlet exchnage. The fraction $R$ shows no significant dependence on ${E}_{T}^{\mathrm{jet}}$ or on the pseudorapidity separation between the jets.

Diamond radiation sensors produced by chemical vapour deposition are studied for the application as tracking detectors in high luminosity experiments. Sensors with a charge collection distance up to 250 μm have been manufactured. Their radiation hardness has been studied with pions, proton and neutrons up to fluences of 1.9×1015π cm−2,5×1015 p cm−2 and 1.35×1015 n cm−2, respectively. Diamond micro-strip detectors with 50 μm pitch have been exposed in a high-energy test beam in order to investigate their charge collection properties. The measured spatial resolution using a centre-of-gravity position finding algorithm corresponds to the digital resolution for this strip pitch. First results from a strip tracker with a 2×4 cm2 surface area are reported as well as the performance of a diamond tracker read out by radiation-hard electronics with 25 ns shaping time. Diamond pixel sensors have been prepared to match the geometries of the recently available read-out chip prototypes for ATLAS and CMS. Beam test results are shown from a diamond detector bump-bonded to an ATLAS prototype read-out. They demonstrate a 98% bump-bonding efficiency and a digital resolution in both dimensions.

To compare intensity-modulated radiotherapy (IMRT) treatment plans with three-dimensional conformal radiotherapy (3D-CRT) plans to investigate the suitability of IMRT for the treatment of tumors of the parotid gland. One 3D-CRT treatment plan and 10 IMRT treatment plans with differing beam arrangements were produced for each of nine patient data sets. The plans were compared using regret analysis, dose conformity, dose to organs at risk, and uncomplicated tumor control probability (UTCP). The target dose was comparable in the 3D-CRT and IMRT plans, although improvements were seen when seven and nine IMRT fields were used. IMRT reduced the mean dose to the contralateral parotid gland and the maximum doses to the brain and the spinal cord, but increased the ipsilateral lens dose in some cases. Each IMRT arrangement produced a higher UTCP than the 3D-CRT plans; the largest absolute difference was 9.6%. IMRT is a suitable means for treating cancer of the parotid, and a five-field class solution is proposed. It produced substantial sparing of organs at risk and higher UTCPs than 3D-CRT and should enable dose escalation.

This report describes a measurement of the top quark mass in $p\overline{p}$ collisions at a center of mass energy of 1.8 TeV. The data sample was collected with the CDF detector during the 1992--1995 collider run at the Fermilab Tevatron, and corresponds to an integrated luminosity of 106 ${\mathrm{pb}}^{\mathrm{\ensuremath{-}}1}$. Candidate $t\overline{t}$ events in the ``$\mathrm{l}\mathrm{e}\mathrm{p}\mathrm{t}\mathrm{o}\mathrm{n}+\mathrm{j}\mathrm{e}\mathrm{t}\mathrm{s}$'' decay channel provide our most precise measurement of the top quark mass. For each event a top quark mass is determined by using energy and momentum constraints on the production of the $t\overline{t}$ pair and its subsequent decay. A likelihood fit to the distribution of reconstructed masses in the data sample gives a top quark mass in the $\mathrm{l}\mathrm{e}\mathrm{p}\mathrm{t}\mathrm{o}\mathrm{n}+\mathrm{j}\mathrm{e}\mathrm{t}\mathrm{s}$ channel of $176.1\ifmmode\pm\else\textpm\fi{}5.1(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}5.3(\mathrm{syst})\mathrm{}\mathrm{GeV}{/c}^{2}.$ Combining this result with measurements from the ``all-hadronic'' and ``dilepton'' decay topologies yields a top quark mass of $176.1\ifmmode\pm\else\textpm\fi{}6.6\mathrm{GeV}{/c}^{2}.$

We present the first observation of the all hadronic decay of $t\overline{t}$ pairs. The analysis is performed using $109{\mathrm{pb}}^{\ensuremath{-}1}$ of $p\overline{p}$ collisions at $\sqrt{s}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1.8\mathrm{TeV}$ collected with the Collider Detector at Fermilab. We observe an excess of events with five or more jets, including one or two $b$ jets, relative to background expectations. Based on this excess we evaluate the production cross section to be in agreement with previous results. We measure the top mass to be $186\ifmmode\pm\else\textpm\fi{}10\ifmmode\pm\else\textpm\fi{}12\mathrm{GeV}{/c}^{2}$.

CVD diamond shows promising properties for use as a position-sensitive detector for experiments in the highest radiation areas at the Large Hadron Collider. In order to study the radiation hardness of diamond we exposed CVD diamond detector samples to 24 Gev/c and 500 Mev protons up to a fluence of 5×1015 p/cm2. We measured the charge collection distance, the average distance electron–hole pairs move apart in an external electric field, and leakage currents before, during, and after irradiation. The charge collection distance remains unchanged up to 1×1015 p/cm2 and decreases by ≈40% at 5×1015 p/cm2. Leakage currents of diamond samples were below 1 pA before and after irradiation. The particle-induced currents during irradiation correlate well with the proton flux. In contrast to diamond, a silicon diode, which was irradiated for comparison, shows the known large increase in leakage current. We conclude that CVD diamond detectors are radiation hard to 24 GeV/c and 500 MeV protons up to at least 1×1015p/cm2 without signal loss.

We present a search for the flavor-changing neutral current decays B0d→μ+μ− and B0s→μ+μ− in p¯p collisions at √s=1.8 TeV, using 98pb−1 of data collected at the Collider Detector at Fermilab. We find one candidate event for these decays, which is consistent with the background estimates, and set upper limits on the branching fractions of B(B0d→μ+μ−)<8.6×10−7 and B(B0s→μ+μ−)<2.6×10−6 at 95% confidence level.Received 21 November 1997DOI:https://doi.org/10.1103/PhysRevD.57.R3811©1998 American Physical Society

We present a measurement of $\sigma \cdot B(W \to e \nu)$ and $\sigma \cdot B(Z^0 \to e^+e^-)$ in proton - antiproton collisions at $\sqrt{s} =1.8$ TeV using a significantly improved understanding of the integrated luminosity. The data represent an integrated luminosity of 19.7 pb$^{-1}$ from the 1992-1993 run with the Collider Detector at Fermilab (CDF). We find $\sigma \cdot B(W \to e \nu) = 2.49 \pm 0.12$~nb and $\sigma \cdot B(Z^0 \to e^+e^-) = 0.231 \pm 0.012$~nb.

We report on a search for B(0)(s)-->micro(+)micro(-) and B(0)(d)-->micro(+)micro(-) decays in pp collisions at square root of s=1.96 TeV using 171 pb(-1) of data collected by the CDF II experiment at the Fermilab Tevatron Collider. The decay rates of these rare processes are sensitive to contributions from physics beyond the standard model. One event survives all our selection requirements, consistent with the background expectation. We derive branching ratio limits of B(B(0)(s)-->micro(+)micro(-))<5.8x10(-7) and B(B(0)(d)-->micro(+)micro(-))<1.5x10(-7) at 90% confidence level.

The inherent properties of diamond make it an ideal material for tracking detectors especially in the high rate, high radiation environments of future colliders such as the LHC. In order to survive in this environment, detectors must be radiation hard. We have constructed charged particle detectors using high quality CVD diamond and performed radiation hardness tests on them. The signal response of diamond detectors to ionizing particles is measured before and after irradiation. Diamond detectors have been exposed to 60Co photons at Argonne National Laboratory, 300 MeV/c pions at PSI, 500 MeV protons at TRIUMF and 5 MeV alpha particles at Los Alamos National Laboratory. The results show that CVD diamond is an extremely radiation hard material well suited for particle detector production.

We update the measurement of the $t\overline{t}$ production cross section using the CDF detector at the Fermilab Tevatron. This measurement uses $t\overline{t}$ decays to the final states $e+\ensuremath{\nu}+\mathrm{jets}$ and $\ensuremath{\mu}+\ensuremath{\nu}+\mathrm{jets}.$ We search for b quarks from t decays via secondary-vertex identification or the identification of semileptonic decays of the b and cascade c quarks. The background to the $t\overline{t}$ production is determined primarily through a Monte Carlo simulation. However, we calibrate the simulation and evaluate its uncertainty using several independent data samples. For a top quark mass of $175\mathrm{GeV}{/c}^{2},$ we measure ${\ensuremath{\sigma}}_{t\overline{t}}=5.1\ifmmode\pm\else\textpm\fi{}1.5\mathrm{pb}$ and ${\ensuremath{\sigma}}_{t\overline{t}}=9.2\ifmmode\pm\else\textpm\fi{}4.3\mathrm{pb}$ using the secondary vertex and the lepton tagging algorithms, respectively. Finally, we combine these results with those from other $t\overline{t}$ decay channels and obtain ${\ensuremath{\sigma}}_{t\overline{t}}{=6.5}_{\ensuremath{-}1.4}^{+1.7}\mathrm{pb}.$

We have used $19{\mathrm{pb}}^{\ensuremath{-}1}$ of data collected with the Collider Detector at Fermilab to search for new particles decaying to dijets. We exclude at 95% confidence level models containing the following new particles: axigluons with mass between 200 and 870 GeV/ ${c}^{2}$, excited quarks with mass between 80 and 570 GeV/ ${c}^{2}$, and color octet technirhos with mass between 320 and 480 GeV/ ${c}^{2}$.

The distributions of quarks in the pion and nucleon are extracted from measurements of the reaction ${\ensuremath{\pi}}^{\ensuremath{-}}N\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}X$ at 253 GeV/c in a naive Drell-Yan analysis, as well as QCD-corrected analyses at leading-log and next-to-leading-log order. As ${x}_{\ensuremath{\pi}}\ensuremath{\rightarrow}1$ the pion structure function shows a term that varies as $\frac{1}{{m}_{\ensuremath{\mu}\ensuremath{\mu}}^{4}}$, which we interpret as a higher-twist effect. Additionally, the angular distribution of the ${\ensuremath{\mu}}^{+}$ in the muon-pair rest frame tends towards ${sin}^{2}\ensuremath{\theta}$ as ${x}_{\ensuremath{\pi}}\ensuremath{\rightarrow}1$ and as ${m}_{\ensuremath{\mu}\ensuremath{\mu}}\ensuremath{\rightarrow}0$ in a manner consistent with higher-twist effects. When the strongly mass-dependent higher-twist effects are included as part of the pion structure function, the nucleon structure function agrees well with leading-twist results from deeply inelastic lepton-hadron scattering. A significant advance of the present work is the extension of the analysis to low masses by the subtraction of the $\frac{J}{\ensuremath{\psi}}$ and ${\ensuremath{\psi}}^{\ensuremath{'}}$ resonances from the continuum. Our analysis covers the kinematic range $0.4&lt;{x}_{\ensuremath{\pi}}&lt;1.0$ and $0.02&lt;{x}_{N}&lt;0.33$ with $3.0&lt;{m}_{\ensuremath{\mu}\ensuremath{\mu}}&lt;8.55$ GeV/${\mathit{c}}^{2}$. Cross sections for ${\ensuremath{\psi}}^{\ensuremath{'}}$ production are presented in an appendix.

Abstract A simple scheme for soil sampling and subsequent analysis for total soil phosphorus using perchloric acid digestion is described and its application illustrated by samples from the native farmstead of the Roman period at Cefn Graeanog in North Wales. The floor deposits of three distinctive buildings were analysed, and the data obtained enhanced by Trend Surface Analysis to produce generalized maps of the phosphorus distribution, together with levels of significance of such distribution patterns. These were then used to clarify the details of the interpretation of the usage of the various types of building. Data for soil phosphorus concentration clearly reveal the pattern of erosion of constructed floors, the presence of features such as hearths and drains, and can be used to reveal patterns not otherwise discernible by excavation techniques.

A measurement of the cross section for the inclusive production of isolated photons by the CDF experiment at the Fermilab Tevatron collider is presented. The measurement covers the pseudorapidity region |ηγ|<1.0 and the transverse energy range EγT>30 GeV and is based on 2.5 fb−1 of integrated luminosity. The sample is almost a factor of 7 larger than those used for recent published results and extends the EγT coverage by 100 GeV. The result agrees with next-to-leading order perturbative QCD calculations within uncertainties over the range 50<EγT<400 GeV, though the energy spectrum in the data shows a steeper slope at lower EγT.Received 20 October 2009DOI:https://doi.org/10.1103/PhysRevD.80.111106©2009 American Physical Society

We present a search for standard model (SM) Higgs boson production using ppbar collision data at sqrt(s) = 1.96 TeV, collected with the CDF II detector and corresponding to an integrated luminosity of 4.8 fb-1. We search for Higgs bosons produced in all processes with a significant production rate and decaying to two W bosons. We find no evidence for SM Higgs boson production and place upper limits at the 95% confidence level on the SM production cross section (sigma(H)) for values of the Higgs boson mass (m_H) in the range from 110 to 200 GeV. These limits are the most stringent for m_H > 130 GeV and are 1.29 above the predicted value of sigma(H) for mH = 165 GeV.

A precision measurement of the top quark mass ${m}_{t}$ is obtained using a sample of $t\overline{t}$ events from $p\overline{p}$ collisions at the Fermilab Tevatron with the CDF II detector. Selected events require an electron or muon, large missing transverse energy, and exactly four high-energy jets, at least one of which is tagged as coming from a $b$ quark. A likelihood is calculated using a matrix element method with quasi-Monte Carlo integration taking into account finite detector resolution and jet mass effects. The event likelihood is a function of ${m}_{t}$ and a parameter ${\ensuremath{\Delta}}_{\mathrm{JES}}$ used to calibrate the jet energy scale in situ. Using a total of 1087 events in $5.6\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of integrated luminosity, a value of ${m}_{t}=173.0\ifmmode\pm\else\textpm\fi{}1.2\text{ }\text{ }\mathrm{GeV}/{c}^{2}$ is measured.

We present the results of a search for pair production of a heavy toplike (t') quark decaying to Wq final states using data corresponding to an integrated luminosity of 5.6 fb(-1) collected by the CDF II detector in pp collisions at √s=1.96 TeV. We perform parallel searches for t'→Wb and t'→Wq (where q is a generic down-type quark) in events containing a lepton and four or more jets. By performing a fit to the two-dimensional distribution of total transverse energy versus reconstructed t' quark mass, we set upper limits on the t't' production cross section and exclude a standard model fourth-generation t' quark decaying to Wb (Wq) with mass below 358 (340) GeV/c(2) at 95% C.L.

We present a measurement of the \CP-violating parameter \betas using approximately 6500 $\BsJpsiPhi$ decays reconstructed with the CDF\,II detector in a sample of $p\bar p$ collisions at $\sqrt{s}=1.96$ TeV corresponding to 5.2 fb$^{-1}$ integrated luminosity produced by the Tevatron Collider at Fermilab. We find the \CP-violating phase to be within the range $\betas \in [0.02, 0.52] \cup [1.08, 1.55]$ at 68% confidence level where the coverage property of the quoted interval is guaranteed using a frequentist statistical analysis. This result is in agreement with the standard model expectation at the level of about one Gaussian standard deviation. We consider the inclusion of a potential $S$-wave contribution to the $\Bs\to J/\psi K^+K^-$ final state which is found to be negligible over the mass interval $1.009 < m(K^+K^-)<1.028 \gevcc$. Assuming the standard model prediction for the \CP-violating phase \betas, we find the \Bs decay width difference to be $\deltaG = 0.075 \pm 0.035\,\textrm{(stat)} \pm 0.006\,\textrm{(syst)} \ps$. We also present the most precise measurements of the \Bs mean lifetime $\tau(\Bs) = 1.529 \pm 0.025\,\textrm{(stat)} \pm 0.012\,\textrm{(syst)}$ ps, the polarization fractions $|A_0(0)|^2 = 0.524 \pm 0.013\,\textrm{(stat)} \pm 0.015\,\textrm{(syst)}$ and $|A_{\parallel}(0)|^2 = 0.231 \pm 0.014\,\textrm{(stat)} \pm 0.015\,\textrm{(syst)}$, as well as the strong phase $\delta_{\perp}= 2.95 \pm 0.64\,\textrm{(stat)} \pm 0.07\,\textrm{(syst)} \textrm{rad}$. In addition, we report an alternative Bayesian analysis that gives results consistent with the frequentist approach.

We present a measurement of the total decay width of the top quark using events with top-antitop-quark pair candidates reconstructed in the final state with one charged lepton and four or more hadronic jets. We use the full Tevatron Run II data set of $\sqrt{s} = 1.96$ TeV proton-antiproton collisions recorded by the CDF II detector. The top-quark mass and the mass of the hadronically-decaying $W$ boson are reconstructed for each event and compared with distributions derived from simulated signal and background samples to extract the top-quark width (\gmt) and the energy scale of the calorimeter jets with {\it in-situ} calibration. For a top-quark mass $\mtop = \gevcc{172.5}$, we find $1.10<\gmt<\gev{4.05}$ at 68% confidence level, which is in agreement with the standard-model expectation of \gev{1.3} and is the most precise direct measurement of the top-quark width to date.

This Letter reports a measurement of the cross section for producing pairs of central prompt isolated photons in proton-antiproton collisions at a total energy of 1.96 TeV using data corresponding to 9.5/fb integrated luminosity collected with the CDF II detector at the Fermilab Tevatron. The measured differential cross section is compared to three calculations derived from the theory of strong interactions. These include a prediction based on a leading order matrix element calculation merged with parton shower, a next-to-leading order, and a next-to-next-to-leading order calculation. The first and last calculations reproduce most aspects of the data, thus showing the importance of higher-order contributions for understanding the theory of strong interaction and improving measurements of the Higgs boson and searches for new phenomena in diphoton final states.

We measure the asymmetry in the charge-weighted rapidity of the lepton in semileptonic ttbar decays recorded with the CDF II detector using the full Tevatron Run II sample, corresponding to an integrated luminosity of 9.4/fb. A parametrization of the asymmetry as a function of the charge-weighted rapidity is used to correct for the finite acceptance of the detector and recover the production-level asymmetry. The result of afb(lep) = 0.094 +0.032 -0.029 is to be compared to the standard model next-to-leading-order prediction of afb(lep) = 0.038 +-0.003.

Farmland hedges could be managed for carbon sequestration, but empirical data on their carbon (C) stock in the UK is lacking. Lowland hedges managed by hedge laying and triennial trimming using a mechanical flail formed a dense woody structure (mean 81,368 stems ha−1). Hedges untrimmed for 3 years (mean height 3.5 m, widths 2.6–4.2 m), contained an above ground biomass (AGB) C stock of 42.0 ± 3.78 t C ha−1 (14.0 ± 1.94 t C km−1); when trimmed to 2.7 m high, and subsequently 1.9 m high, AGB C stocks were reduced to 40.6 ± 4.47 t C ha−1 (11.4 t C km−1) and 32.2 ± 2.76 t C ha−1 (9.9 t C km−1), respectively. A 4.2 m wide hedge contained 9.7 t C km−1 more AGB C stock than a 2.6 m wide hedge (mean height 3.5 m). Below ground biomass (BGB) was 38.2 ± 3.66 t C ha−1 (11.5 t C km−1). Near horizontal stems, arranged by hedge laying, 12–18 years prior to sampling, accounted for 5.2 t C ha−1 (1.6 t C km−1) of AGB C. The empirical data demonstrated how changing management practices to wider/taller hedges sequestered C in AGB. These estimates of hedgerow C stocks fill a knowledge gap on C storage and identified the need for a more comprehensive biomass inventory of hedgerows to strengthen the national carbon accounting of agro-ecosystems in the UK.

Dryland smallholders are faced with the challenges of achieving resilience and agricultural sustainability. This is in addition to constraints such as lack of capital, inputs, and often poor extension services. The risk of extreme weather events poses a great challenge to food security in drylands as the impacts of climate change increases. This paper examines the challenges faced by smallholders and the limitations of traditional farming systems in Sudano-Sahelian zones amidst climate change and emerging armed conflicts with special focus on the Sudano-Sahelian Nigerian drylands. The review reports three key findings as follows: first, smallholders have been active in managing short-term environmental risks and challenges by using local knowledge to improve production and short-term resilience. Secondly, concerns about potential longer-term climatic changes such as longer droughts, desertification, the impact of the drying of the Lake Chad, armed conflicts and extreme weather events could hinder resilience. Third, an increasing rainfall variability, soil/nutrient degradation and farming systems adopted could limit or undermine resilience strategies, especially if new environmental challenges exceed those previously experienced. This review suggests a need for additional research into innovative drylands’ sustainability and resilience practices in response to a changing climate linked to other social challenges.

We report the first observation of dijet events with a double Pomeron exchange topology produced in &pmacr;p collisions at sqrt[s] = 1800 GeV. The events are characterized by a leading antiproton, two jets in the central pseudorapidity region, and a large rapidity gap on the outgoing proton side. We present results on jet kinematics and production rates, compare them with corresponding results from single diffractive and inclusive dijet production, and test factorization.