J. Rander

We have searched for νμ oscillations by comparing the rates of νgm charged-current interactions in two detectors located 130 and 885 m from the target, which was struck by a 9.2 GeV/c proton beam from the CERN Proton Synchroton. No evidence for νμ oscillations was found. At the 90% confidence level, Δm2 values between 0.26 and 90 eV2 are excluded for maximal mixing. The most restrictive limit on the neutrino mixing-angle parameter sin22θ is 0.053 at Δm2=2.5 eV2.

We present results on charged current inclusive neutrino and antineutrino scattering in the neutrino energy range 30–200 GeV. The results include a) total cross-sections; b)y distributions; c) structure functions; and d) scaling violations observed in the structure functions. The results, as well as their comparison with the results of electron and muon inclusive scattering, are in agreement with the expectations of the quark parton model and QCD.

A large sample of opposite-sign dimuons, produced by the interaction of neutrinos and antineutrinos in iron, is analysed. The data agree very well with the hypothesis that the extra muon is the product of charm decay. They yield information on the strength and space-time structure of the charmproducing weak current. The strange-sea structure functionxs(x) is determined. The difference between neutrino and antineutrino dimuon production is analysed to provide a value of the Kobayashi-Maskawa weak mixing angleθ 2.

The energy resolution and response of a segmented iron-scintillator total absorption calorimeter has been measured for pion energies from 10 to 140 GeV and for electron energies up to 50 GeV. A procedure has been found to weight individual counter responses for hadron showers which results in improved energy resolution at high energies and a nearly linear dependence of response on hadron energy above 30 GeV. There is evidence in the data that this weighting procedure compensates for fluctuations in energy deposition due to the electromagnetic component of the hadronic shower. For an iron sampling thickness of 2.5 cm the hadron energy resolution follows a 0.58E law, while the resolution for electromagnetic showers is 0.23E.

Inclusive charged-current interactions of high-energy neutrinos and antineutrinos have been studied with high statistics in a counter experiment at the CERN Super Proton Synchrotron. The energy dependence of the total cross-sections, the longitudinal structure function, and the nucleon structure functionsF 2,xF 3, and $$\bar q^{\bar v} $$ are determined from these data. The analysis of theQ 2-dependence of the structure functions is used to test quantum chromodynamics, to determine the scale parameter Λ and the gluon distribution in the nucleon.

We report results from a beam dump experiment that has been performed at the CERN SPS neutrino facility using the CDHS neutrino counter detector. Limits on dimuon and trimuon production by new penetrating neutral particles are given. A new source of prompt electron and muon neutrinos has been observed giving (1.2±0.4)× 10−7 νe or νμ per incident proton with neutrino angle smaller than 1.85 mrad and Eν > 20 GeV. If these prompt neutrinos are attributed to charmed meson pair production, the inclusive DD production cross section could be of the order of 30 ωb. If axions are existing their production rate relative to π0 mesons is found to be less than 0.5 × 10−8.

The CDHS neutrino detector has been used to measure events originating in a tank of liquid hydrogen and in the iron of the detector. Total cross-sections, differential cross-sections, and structure functions are given for hydrogen and compared with those in iron. The measurements are in agreement with the expectations of the quark parton model. No significant differences indicative of nuclear binding effects in corresponding structure functions of protons and iron are observed. This may be of special interest in the case of the sea structure functions, since large differences are expected in some models.

The structure functions F2(x, Q2) and xF3(x, Q2) measured in high-energy neutrino charged-current interactions on nuclei are compared with QCD predictions. Solutions to the moment equations of QCD are found which are in good agreement with the data and yield simple parametrisations of the structure functions. For the scale parameter Λ we find Λ = 0.5 ± 0.2 GeV. The analysis also results in values for the width of the gluon distribution as a function of Q2. We find 〈x〉gluons = 0.16 ± 0.03 for Q2 = 10 GeV2.

On the basis of 315 dimuon events of opposite sign for which the nature (and energy) of the incident neutrino is known, and the momenta and hadronic shower energy are measured, we find a) very similar production by neutrinos and antineutrinos, and therefore confirmation of the GIM model for semileptonic weak interactions, b) energy spectra, excitation functions, angular correlations and transverse momentum distributions which are in remarkable agreement with the hypothesis of charm production and decay, c) evidence against models for which the second muon has a heavy lepton as origin, d) evidence against “bottom” quark production by antineutrinos, e) the amount and the structure function for the strange quark-antiquark sea, and f) an approximate branching ratio, of 0.15 for the muonic decay of the semistable charmed meson.

We describe the design, construction and performance of a large mass detector used at CERN to study high-energy neutrino interactions in iron. This detector combines magnetic spectrometry and hadron calorimetry techniques.

We have analyzed data taken in the CERN narrow-band neutrino and antineutrino beams with regard to the "high-$y$ anomaly" observed by previous experiments at Fermilab. At neutrino energies between 30 and 200 GeV, the $\overline{\ensuremath{\nu}}$ and $\ensuremath{\nu}$ charged-current cross-section ratios and muon-inelasticity distributions disagree with the earlier results. In particular, there is no evidence for energy-dependent effects in the antineutrino data which constitute an important aspect of the alleged anomaly.

A search for the charmed baryon, Λc+, has been carried out in inclusively, measured Λ0π±π+π− and K−π±p final states with longitudinal x > 0.75 in an experiment at the CERN intersecting storage rings. An effect with invariant mass near 2.3 GeV is observed in Λ0π+π+π− with cross section times branching ratio Bσ = (2.8±1.0) μb; similar effect is observed in K−π+p with Bσ = (2.3 ± 0.3) μb. The effect is seen only in the positive charge state, in agreement with an interpretation as Λc+. However, it is pointed out that in the same experiment, the non-charmed hyperon state Σ(1385)+ also has a cross section much larger than its corresponding negative charge state Σ(1385)−.

The observed scaling violations of the nucleon structure functionF 2 and $$\bar q$$ have been analysed in the framework of perturbative QCD to determine the shape and magnitude of the gluon distribution. The data are in good agreement with leading order QCD, and the simultaneous use ofF 2 and $$\bar q$$ structure functions permits, for the first time, a reliable determination of the gluon structure function.

We have calibrated a magnetized iron-scintillator sandwhich calorimeter in a hadron beam, finding an energy resolution equal to 16% fwhm at 140 GeV with 5 cm sampling. The hadron energy resolution (fwhm/mean) improves as E−12 between 15 and 140 GeV. No effect due to the magnetic field was observed. Longitudinal and lateral shower containment were also investigated.

We report on results from a study of hadron-energy distributions for ν and ν inclusive neutral current interactions. There is no significant variation of the neutral to charged current total cross-section ratios Rν and Rν with neutrino energy. The space-time structure of neutral currents is dominated by V−A, with a significant admixture of V+A. The Weinberg-Salam model is in agreement with all data if sin2θw=0.24±0.02.

We present moments (both ordinary and Nachtmann) of the nucleon valence structure function measured in high Q2νFE scattering, supplemented by data from deep inelastic eD scattering. These data seem to agree with QCD predictions for vector gluons. The QCD parameter Λ is found to be of the order 0.5 GeV.

Λ0's produced in the inclusive reaction pp → Λ° + X with √s = 53 and 62 GeV at the CERN Intersecting Storage Rings are observed to be polarized along the normal to the production plane. In the ranges of longitudinal and transverse momenta, 15–24 and 0.6-1.4 GeV/c, respectively, the mean polarization is found to be −(0.357±0.055).

We report on the analysis of inclusive neutral current events produced in neutrino and antineutrino narrow band beams. We find for incident neutrino energies in the range 12–200 GeV and for hadron energies above 12 GeV a neutral to charged current cross-section ratio of Rv = 0.293 ± 0.010 for incident neutrinos, and Rv = 0.35 ± 0.03 for antineutrinos. These ratios are consistent with the Weinberg-Salam model, with sin2θw = 0.24 ± 0.02.

Accelerated protons and ions are observed when an intense relativistic electron stream is propagated through a gas-filled region. Several proton momentum peaks are observed for each stream pulse with a spread of \ensuremath{\le}10%, consistent with our resolution. Proton energies are independent of the filling gas for ${\mathrm{H}}_{2}$, ${\mathrm{N}}_{2}$, and air. Total ion fluxes are ${10}^{13}$ to ${10}^{15}$ particles/stream pulse. Nitrogen-ion tracks were too short to determine the charge state and hence the energy, but estimated upper limits suggest +4 or +5, consistent with the energy-to-change ratio observed for protons.

Neutrino and antineutrino total charged current cross sections on iron were measured in the 100, 160, and 200 GeV narrow band beams at the CERN SPS in the energy range 10 to 200 GeV. Assuming σ/E to be constant, the values corrected for non-isoscalarity are σv/E = (0.686 ± 0.019) * 10−38 cm2/ (GeV · nucleon) and σv/E = (0.339 ± 0.010) * 10−38 cm2/ (GeV·nucleon). Between 50 and 150 GeV no energy dependence of σ/E was observed within ±3% for neutrino and ±4% for antineutrino interactions.

We report on the multiple wavelength laser monitoring system designed for the compact muon solenoid (CMS) lead tungstate crystal calorimeter. Results are presented for the test-beam performance of the system designed to achieve ⩽0.2% relative optical transmittance inter-calibration for 75 848 lead tungstate crystals. The system cycles continuously over the calorimeter to follow each crystal's evolution under the irradiation and recovery periods foreseen during operation at the LHC.

Inclusive measurements of Λ0, Λ0, Ξ−, Σ(1385)±) production in the forward direction at the CERN intersecting storage rings are presented. A signal for simulataneous Λ0Λ0 production is also observed with total x > 0.6, 2.3 < MΛΛ < 2.5 GeV and with a cross section of (1.7 ± 0.2) μb.

The single diffraction dissociation process pp → (pπ+π−)p has been studied at the CERN ISR at √s = 45 GeV and 0.1 < −t < 0.6 GeV2. The reaction is dominated by nucleon resonance production: pp → pN (1520) and pp → pN(1688) with cross-sections (0.25 ± 0.08) mb and (0.56 ± 0.19) mb respectively.

The result of a search at the LHC for heavy stable charged particles produced in pp collisions at $ \sqrt {s} = 7\;{\text{TeV}} $ is described. The data sample was collected with the CMS detector and corresponds to an integrated luminosity of 3.1 pb−1. Momentum and ionization-energy-loss measurements in the inner tracker detector are used to identify tracks compatible with heavy slow-moving particles. Additionally, tracks passing muon identification requirements are also analyzed for the same signature. In each case, no candidate passes the selection, with an expected background of less than 0.1 events. A lower limit at the 95% confidence level on the mass of a stable gluino is set at 398GeV/c 2, using a conventional model of nuclear interactions that allows charged hadrons containing this particle to reach the muon detectors. A lower limit of 311 GeV/c 2 is also set for a stable gluino in a conservative scenario of complete charge suppression, where any hadron containing this particle becomes neutral before reaching the muon detectors.

Hadronic event shapes have been measured in proton-proton collisions at sqrt(s)=7 TeV, with a data sample collected with the CMS detector at the LHC. The sample corresponds to an integrated luminosity of 3.2 inverse picobarns. Event-shape distributions, corrected for detector response, are compared with five models of QCD multijet production.

A measurement of the top-antitop production cross section in proton-proton collisions at a centre-of-mass energy of 7 TeV has been performed at the LHC with the CMS detector. The analysis uses a data sample corresponding to an integrated luminosity of 36 inverse picobarns and is based on the reconstruction of the final state with one isolated, high transverse-momentum electron or muon and three or more hadronic jets. The kinematic properties of the events are used to separate the top-antitop signal from W+jets and QCD multijet background events. The measured cross section is 173 + 39 - 32 (stat. + syst.) pb, consistent with standard model expectations.

The charge asymmetry in the production of top quark and antiquark pairs is measured in proton-proton collisions at a center-of-mass energy of 8 TeV. The data, corresponding to an integrated luminosity of 19.6 inverse femtobarns, were collected by the CMS experiment at the LHC. Events with a single isolated electron or muon, and four or more jets, at least one of which is likely to have originated from hadronization of a bottom quark, are selected. A template technique is used to measure the asymmetry in the distribution of differences in the top quark and antiquark absolute rapidities. The measured asymmetry is A[c,y] = [0.33 +/- 0.26 (stat) +/- 0.33 (syst)]%, which is the most precise result to date. The results are compared to calculations based on the standard model and on several beyond-the-standard-model scenarios.

Forty seven events of the type v + Fe → μ− + μ− + X and nine events of the type v + Fe → μ+ + μ+ + X have been observed, and zero events with like-sign muons of the opposite sign. Most of the observed events can be attributed to the background of normal charged current events, in which one of the pions or kaons of the hadron shower decays, and so produces a second muon. The remaining events correspond to rates of the order of (3 ± 2) × 10−4 of those for charged current events. They may very well be due to the hadronic production of a charm-anticharm pair, with subsequent decay of one member of the pair. The observed rates correspond to charm-anticharm pair production in 0.5–1% of the hadron showers. No evidence can be found for a lepton-cascade origin of the observed events.

The properties of 76 neutrino-initiated μ−μ−μ+ events observed in the CDHS detector in the 350 GeV and 400 GeV wide-band beams at CERN are discussed. For neutrino energies 30 GeV and muon momenta ≳4.5 GeV, the average trimuon rate is (3.0 ± 0.4) × 10−5 of the single-muon event rate. The experimental distributions are compared with predictions from various models. The data cannot be understood in terms of either heavy-lepton or heavy-quark cascades; no evidence is found for such processes and upper limits for the two possibilities are established. The data can be understood in terms of the normal charged-current process with the additional production of a muon pair by both hadronic and electromagnetic processes.

We report two trimuon events producedin v interactions. Of these, one is of the charge type −++, not previously reported. In an antineutrino exposure, one candidate of the charge type +−− has been observed. This type of event has also not been reported previously. The combined π → μ and K → μ background for the three events are calculated to be ∼ 0.7 events. The rate relative to charged current events corresponding to these three events is of the order of 4 × 10−5.

290 events of the type νFe→μ−μ−X and 53 events from the reaction νFe→μ+μ+X withEν>30GeV and muon momenta pμ>6.5GeV/c have been observed in the CDHS detector. After subtracting the background from charged-current processes with one π or K meson of the hadronic shower decaying into μ−ν(or μ+μ), we obtain for neutrinos a rate of prompt like- sign dimuon production of (3.4±1.8)×10−5 relative to the rate of charged-current events with the same cuts, or (4.1 ± 2.2)% relative to the prompt μ−μ+ rate, and for antineutrinos the corresponding relative rates (4.3±2.3)×10−5 and (4.2 ± 2.3)%. A possible explanation for the events is charm pair production at a level of 10−3 relative to all charged-current reactions.

Ions are accelerated when a high-current relativistic electron beam is injected into a low-pressure gas-filled region. A correlation is observed between electron-beam front velocities in hydrogen and mean proton velocities that places an upper limit on the length of the acceleration region and indicates that the net beam-current rise is preceded by the protons after particle acceleration. The apparent field strengths in the acceleration region are \ensuremath{\ge} (3 to 6) \ifmmode\times\else\texttimes\fi{} ${10}^{7}$ V/m.

A search has been made for neutrino interactions with a positive (wrong-sign) muon in the final state. All the events found can be attributed to known sources. A cut at a visible energy of 100 GeV leaves one event, giving an upper limit for μ+ production relative to μ- of 1.6 × 10−4 at the 90% confidence level. Upper limits are given for (a) charm-changing neutral currents, (b) positive heavy-lepton production, and (c) neutrino-antineutrino oscillations.

Right handed weak quark currents coupled to the usual left handed weak lepton current would be seen in inclusive antineutrino scattering on nuclei as a contribution at largey with the quark (not antiquark) structure function. We do not see such a term, and can therefore put an upper limit on the relative strengths of such right handed currents: $$\varrho ^2 = \frac{{\sigma _R }}{{\sigma _L }}< 0.009$$ , 90% confidence. This measurement puts limits on the mixing angle of left-right symmetric models. In distinction to similar limits derived from muon decay or β decay, our limits are also valid if the right handed neutrino is heavy.

In the interactions of 400 GeV/c protons with copper nuclei, a flux of prompt neutrinos is observed. The reactions produced by these neutrinos in our apparatus appear consistent with those of electron- and muon-neutrinos. The prompt neutrino fluxes are interpreted as being due to associated production and subsequent semileptonic decay of charmed hadrons. The prompt flux ratio $$\bar v_\mu /v_\mu = 0.46_{ - 0.16}^{ + 0.21} $$ suggests a sizeable production of charmed baryons near the forward direction. The ratio of prompte −+e + toµ −+µ + event rates is 0.64 −0.15 +0.22 , where unity is expected frome-μ universality.

Inclusive cross sections are presented for $2\ensuremath{\pi}$ and $3\ensuremath{\pi}$ systems with large longitudinal $x$ at the highest intersecting storage ring energies ($\sqrt{s}=53$ GeV for $2\ensuremath{\pi}$; $\sqrt{s}=53 \mathrm{and} 62$ GeV for $3\ensuremath{\pi}$). The ratio $\frac{{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}}{{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{\ensuremath{-}}}$ rises sharply with increasing $x$ similar to the ratio $\frac{{K}^{+}}{{K}^{\ensuremath{-}}}$, as expected in a quark-model interpretation.

The properties of 76 neutrino-initiated μ−μ−μ+ events observed in the CDHS detector in the 350 GeV and 400 GeV wide-band beams at the CERN SPS are discussed. For neutrino energies > 30 GeV and muon momenta ≳ 4.5 GeV, the average trimuon rate is (3.0±0.4)×10−5 of the single-muon event rate. The data are in agreement with normal charged-current interactions with the additional production of a muon pair by both hadronic and radiative processes. No evidence is found for either heavy-lepton or heavy-quark cascades. Upper limits for these two possibilities are established.

A new measurement of the ratio R = σL/σT of longitudinal and transverse structure functions in neutrino interactions on iron between 30 and 190 GeV neutrino energy is reported. The result is given as a function of the scale parameter x and the inelasticity ν of the interaction. The average value is R = 0.10 ± 0.07 around ν ≈ 50 GeV and is in accordance with a prediction from the QCD theory.

Abstract We report the observation of double diffraction dissociation in the process p + p → (p π + π − ) + X at √ s of 45 GeV and momentum transfer in the − t range 0.15−0.53 GeV 2 at the CERN ISR. The relative rates for elastic, single and double dissociation reactions measured here are found to agree with the prediction of Pomeron factorization.

Abstract In a single-arm magnetic spectrometer experiment at the CERN Intersecting Storage Rings (ISR), a prominent diffractive enhancement is observed for inclusive production of (pπ+π−) systems near x ∼ 1 at √s = 53 and 35 GeV. In testing limiting fragmentation and scaling for this system, inclusive pπ+π− diffractive excitation into a fixed invariant mass range is found to possess a cross-section independent of s to within (3 ± 5)%. The main component in the (pπ+π−) system is Δ(1236)π, with a charge structure compatible with the break-up of an isotopic spin 1 2 system.

Neutrinos are elementary particles electrically neutral which belong to the family of leptons. As a consequence and in first approximation they only undergo weak processes. This gives them very special properties. They are ideal tools to study precisely the weak interactions, but there is a price to pay: neutrinos are characterized by extremely low probabilities of interactions, they easily penetrate large amount of matter without being stopped. Consequently, it is hard to perform neutrino physics measurements. In practice the difficulty is twofold: in order to accumulate enough statistics, experiments must rely on huge fluxes traversing huge detectors, the number of interactions being obviously proportional to these two factors. As a corollary, backgrounds are difficult to handle because they appear much more commonly than good events. Nevertheless, neutrino interactions have been detected from a variety of sources, both man-made and natural, from very low to very large energies.The aim of this review is to survey our current knowledge about interaction cross sections of neutrinos with matter across all pertinent energy scales. We will see that neutrino interactions cover a large range of processes: nuclear capture, inverse beta-decay, quasi-elastic scattering, resonant pion production, deep inelastic scattering and ultra-high energy interactions.All the gathered information will be used to study weak properties of matter but it will also allow to explore the properties of the neutrinos themselves. In particular, the known three different flavors of neutrinos have different behaviors inside matter and this will be relevant to give some precious understanding about their intrinsic parameters in particular their masses and mixings.As a second order process, neutrinos can undergo electromagnetic interactions. This will also be discussed. Although the corresponding phenomena are not yet experimentally proven by actual measurements, the theory is able to calculate them and it is useful to discuss the topic since it may become an important issue to test ideas of cosmological relevance.This review will mainly adopt an experimental point of view. Strong emphasis will be placed on important detectors which have illustrated the challenging progresses in neutrino physics; they will be described and their results confronted to theoretical predictions.

In a magnetic spectrometer experiment at the CERN Intersecting Storage Rings (ISR), evidence is obtained for the existence of double diffractive excitation in the reaction pp → (pπ+π−) + X at 〈pt2〉 = 0.03 GeV2 and S = 53 GeV. X is observed to be a multi-body low-mass system 12% of the time, in agreement with the same rate observed in pp → p + X.

MethodsHash-ADC system using programmable gate arrays.readout ol the l22S8 pads of the detector.Trigger decisions are generated from a rapid tailed information concerning shower developement is obtained from zero-suppressed azimuthal acceptance for Bhabha scattering over polar angles from 24 to 58 mrad.De LEP § O.l % is described.The detector uses homogeneous construction to give full calorimeter built to achieve an experimental luminosity measurement precision at The design, construction and performance of a silicon-tungsten electromagnetic

The design, construction, and performance of a multiware proportional chamber (MWPC) system (∼10 k wires) constructed for use at the CERN Intersecting Storage Rings (ISR) is described. This system employs hybrid integrated circuity for pulse detection and storage, and is read out via a CAMAC compatible system. The chambers plus two large-aperture magnets with accompanying scintillation and Cherenkov counters form a versatile multiparticle spectrometer system which has been used to investigate particle systems produced near 0° at the CERN ISR.

Experimental evidence for the diffractive production ofΨmesons in weak neutral current reactions is reported. The spectrum-averaged cross section for this process isσdiff = (4.2±1.5) × 10−41cm2/nucleon, in agreement with gluonfusion models, but at variance with vector dominance calculations.

From exposures of the CDHS detector at the CERN SPS we have obtained 367μ + μ − events in neutrino beams and 73μ + μ + events in an antineutrino beam. The magnitude of a prompt like-sign signal has been controversial in the past and moreover could not be explained by known production mechanisms. A critical discussion of the experimental situation is given. We have tried to reduce the systematic uncertainties of previous experiments and to get more information on the dependence of the signal with energy and the muon momentum cut-off. This experiment yields a signal of 2.8σ (2.4σ) of prompt like-sign dimuon events in the case of neutrinos (antineutrinos). The rate to charged current events is of the order of 10−4 forp μ<9GeV andE>100 GeV. The prompt signal has all the properties expected from the production and decay of charm-anticharm events. The magnitude, however, is substantially higher then the prediction of perturbative QCD but lower than some other experiments.

A search is performed for the production of a massive W′ boson decaying to a top and a bottom quark. The data analysed correspond to an integrated luminosity of 19.7 fb−1 collected with the CMS detector at the LHC in proton-proton collisions at $$ \sqrt{s}=8 $$ TeV. The hadronic decay products of the top quark with high Lorentz boost from the W′ boson decay are detected as a single top flavoured jet. The use of jet substructure algorithms allows the top quark jet to be distinguished from standard model QCD background. Limits on the production cross section of a right-handed W′ boson are obtained, together with constraints on the left-handed and right-handed couplings of the W′ boson to quarks. The production of a right-handed W′ boson with a mass below 2.02 TeV decaying to a hadronic final state is excluded at 95% confidence level. This mass limit increases to 2.15 TeV when both hadronic and leptonic decays are considered, and is the most stringent lower mass limit to date in the tb decay mode.

Abstract Eight μ + μ + μ − events have been observed in the CDHS detector during the 330 GeV and 350 GeV antineutrino wide-band beam exposures at CERN. The corresponding average trimuon rate relative to the single-muon rate is (1.8 ± 0.6) × 10 −5 for visible energy ⩾ 30 GeV and muon momenta ⩾ 4.5 GeV c . Some characteristics of these antineutrino trimuon events are compared with μ − μ − μ + events produced by neutrinos.

A search for massive resonances decaying to a Z boson and a photon is performed in events with a hadronically decaying Z boson candidate, separately in light-quark and b quark decay modes, identified using jet substructure and advanced b tagging techniques. Results are based on samples of proton-proton collisions collected with the CMS detector at the LHC at center-of-mass energies of 8 and 13 TeV, corresponding to integrated luminosities of 19.7 and 2.7 inverse femtobarns, respectively. The results of the search are combined with those of a similar search in the leptonic decay modes of the Z boson, based on the same data sets. Spin-0 resonances with various widths and with masses in a range between 0.2 and 3.0 TeV are considered. No significant excess is observed either in the individual analyses or the combination. The results are presented in terms of upper limits on the production cross section of such resonances and constitute the most stringent limits to date for a wide range of masses.

The inelastic hadronic cross section in proton-lead collisions at a centre-of-mass energy per nucleon pair of 5.02 TeV is measured with the CMS detector at the LHC. The data sample, corresponding to an integrated luminosity of 12.6 +/- 0.4 inverse nanobarns, has been collected with an unbiased trigger for inclusive particle production. The cross section is obtained from the measured number of proton-lead collisions with hadronic activity produced in the pseudorapidity ranges 3<abs(eta)<5 and/or -5<abs(eta)<-3, corrected for photon-induced contributions, experimental acceptance, and other instrumental effects. The inelastic cross section is measured to be sigma[inel,pPb]=2061 +/- 3 (stat) +/- 34 (syst) +/- 72 (lum) mb. Various Monte Carlo generators, commonly used in heavy ion and cosmic ray physics, are found to reproduce the data within uncertainties. The value of sigma[inel,pPb] is compatible with that expected from the proton-proton cross section at 5.02 TeV scaled up within a simple Glauber approach to account for multiple scatterings in the lead nucleus, indicating that further net nuclear corrections are small.

A measurement of the ttbar production cross section at sqrt(s)=13 TeV is presented using proton-proton collisions, corresponding to an integrated luminosity of 2.3 inverse femtobarns, collected with the CMS detector at the LHC. Final states with one isolated charged lepton (electron or muon) and at least one jet are selected and categorized according to the accompanying jet multiplicity. From a likelihood fit to the invariant mass distribution of the isolated lepton and a jet identified as coming from the hadronization of a bottom quark, the cross section is measured to be sigma(ttbar)= 835 +/- 3 (stat) +/- 23 (syst) +/- 23 (lum) pb, in agreement with the standard model prediction. Using the expected dependence of the cross section on the pole mass of the top quark (m[t]), the value of m[t] is found to be 172.7+2.4-2.7 GeV.

Memorial Volume for Jack Steinberger, pp. 95-99 (2022) No AccessQCD ANALYSIS OF CHARGED-CURRENT STRUCTURE FUNCTIONSJ.G.H. de GROOT, T. HANSL, M. HOLDER, J. KNOBLOCH, J. MAY, H.P. PAAR, P. PALAZZI, A. PARA, F. RANJARD, D. SCHLATTER, J. STEINBERGER, H. SUTER, W. von RÜDEN, H. WAHL, S. WHITAKER, E.G.H. WILLIAMS, F. EISELE, K. KLEINKNECHT, H. LIERL, G. SPAHN, H.J. WILLUTZKI, W. DORTH, F. DYDAK, C. GEWENIGER, V. HEPP, K. TITTEL, J. WOTSCHACK, P. BLOCH, B. DEVAUX, S. LOUCATOS, J. MAILLARD, J.P. MERLO, B. PEYAUD, J. RANDER, A. SAVOY-NAVARRO, R. TURLAY, and F.L. NAVARRIAJ.G.H. de GROOTCERN, Geneva, Switzerland, T. HANSLCERN, Geneva, Switzerland, M. HOLDERCERN, Geneva, Switzerland, J. KNOBLOCHCERN, Geneva, Switzerland, J. MAYCERN, Geneva, Switzerland, H.P. PAARCERN, Geneva, Switzerland, P. PALAZZICERN, Geneva, Switzerland, A. PARACERN, Geneva, Switzerland, F. RANJARDCERN, Geneva, Switzerland, D. SCHLATTERCERN, Geneva, Switzerland, J. STEINBERGERCERN, Geneva, Switzerland, H. SUTERCERN, Geneva, Switzerland, W. von RÜDENCERN, Geneva, Switzerland, H. WAHLCERN, Geneva, Switzerland, S. WHITAKERCERN, Geneva, Switzerland, E.G.H. WILLIAMSCERN, Geneva, Switzerland, F. EISELEInstitut für Physik der Universität, Dortmund, Germany, K. KLEINKNECHTInstitut für Physik der Universität, Dortmund, Germany, H. LIERLInstitut für Physik der Universität, Dortmund, Germany, G. SPAHNInstitut für Physik der Universität, Dortmund, Germany, H.J. WILLUTZKIInstitut für Physik der Universität, Dortmund, Germany, W. DORTHInstitut für Hochenergiephysik der Universität Heidelberg, Germany, F. DYDAKInstitut für Hochenergiephysik der Universität Heidelberg, Germany, C. GEWENIGERInstitut für Hochenergiephysik der Universität Heidelberg, Germany, V. HEPPInstitut für Hochenergiephysik der Universität Heidelberg, Germany, K. TITTELInstitut für Hochenergiephysik der Universität Heidelberg, Germany, J. WOTSCHACKInstitut für Hochenergiephysik der Universität Heidelberg, Germany, P. BLOCHD.Ph.P.E., CEN-Saclay, France, B. DEVAUXD.Ph.P.E., CEN-Saclay, France, S. LOUCATOSD.Ph.P.E., CEN-Saclay, France, J. MAILLARDD.Ph.P.E., CEN-Saclay, France, J.P. MERLOD.Ph.P.E., CEN-Saclay, France, B. PEYAUDD.Ph.P.E., CEN-Saclay, France, J. RANDERD.Ph.P.E., CEN-Saclay, France, A. SAVOY-NAVARROD.Ph.P.E., CEN-Saclay, France, R. TURLAYD.Ph.P.E., CEN-Saclay, France, and F.L. NAVARRIAIstituto di Fisica dell'Università, Bologna, Italyhttps://doi.org/10.1142/9789811264436_0018Cited by:0 (Source: Crossref) PreviousNext AboutSectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack CitationsRecommend to Library ShareShare onFacebookTwitterLinked InRedditEmail Abstract: The structure functions F2(x, Q2) and xF3(x, Q2) measured in high-energy neutrino charged-current interactions on nuclei are compared with QCD predictions. Solutions to the moment equations of QCD are found which are in good agreement with the data and yield simple parametrisations of the structure functions. For the scale parameter Λ we find Λ = 0.5 + 0.2 GeV. The analysis also results in values for the width of the gluon distribution as a function of Q2. We find (x)gluons = 0.16 ± 0.03 for Q2 = 10 GeV2. Reprinted from Physics Letters B, Vol. 82, J.G.H. de Groot et al., QCD analysis of charged-current structure functions, pp. 456–460, Copyright (1979), with permission from Elsevier. FiguresReferencesRelatedDetails Recommended Memorial Volume for Jack SteinbergerMetrics History PDF download

Induced signals on field corrector wires are used to resolve the right-left ambiguity in a large planar drift chamber. Efficient separation is obtained for ±3 cm drift cells, 4 m long. Technical problems involved in the method, in particular the severe geometrical constraints, are discussed. Important features of the avalanche asymmetry can be inferred from the measurements.

The properties of 76 neutrino‐initiated μ−μ−μ+ events observed in the CDHS detector in the 350 GeV and 400 GeV wide‐band beams at the CERN SPS are discussed. For neutrino energies ≳30 GeV and muon momenta ≳4.5 GeV, the average trimuon rate is (3.0±0.4) ×10−5 of the single‐muon event rate. The data are in agreement with normal charged‐current interactions with the additional production of a muon pair by both hadronic and radiative processes. No evidence is found for either heavy‐lepton or heavy‐quark cascades. Upper limits for these two possibilities are established.

Abstract A readout scheme using information from both anode and cathode planes of liquid argon calorimeters has been investigated. The feasibility of this scheme is demonstrated from data taken with a test calorimeter. The main features of a design for the LEP experiment ALEPH, using this scheme, are given.