G. Majumder

We report the first observation of a narrow charmmonium state produced in the exclusive decay process B+->K+ pi+pi- J/psi. This state, which decays into pi+pi-J/psi, has a mass of 3871.8+-0.7(stat)+-0.4(syst) MeV, which is very near the M_D + M_D* mass threshold. The results are based on an analysis of 152M BBbar events collected at the Upsilon(4S) resonance in the Belle detector at the KEKB collider.

We have measured the branching fraction and photon energy spectrum for the radiative penguin process b-->s gamma. We find Beta(b-->s gamma) = (3.21+/-0.43+/-0.27(+0.18)(-0.10))x10(-4), where the errors are statistical, systematic, and from theory corrections. We obtain first and second moments of the photon energy spectrum above 2.0 GeV, <E( gamma)> = 2.346+/-0.032+/-0.011 GeV, and <E(2)(gamma)>-<E(gamma)>(2) = 0.0226+/-0.0066+/-0.0020 GeV(2), where the errors are statistical and systematic. From the first moment, we obtain (in the modified minimal subtraction renormalization scheme, to order 1/M(3)(B) and beta(0)alpha(2)(s)) the heavy quark effective theory parameter Lambda = 0.35+/-0.08+/-0.10 GeV.

We report the observation of a near-threshold enhancement in the omegaJ/psi invariant mass distribution for exclusive B-->KomegaJ/psi decays. The results are obtained from a 253 fb(-1) data sample that contains 275 x 10(6) BB pairs that were collected near the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric energy e(+)e(-) collider. The statistical significance of the omegaJ/psi mass enhancement is estimated to be greater than 8sigma.

We report the observation of prompt J/psi via double cc; production from the e+e- continuum. In this process one cc; pair fragments into a J/psi meson while the remaining pair either produces a charmonium state or fragments into open charm. Both cases have been experimentally observed. We find cross sections of sigma[e+e- -->J/psieta(c)(gamma)]xB(eta(c)-->>or=4 charged)=(0.033(+0.007)(-0.006)+/-0.009) pb and sigma(e+e- -->J/psiD(*+)X)=(0.53(+0.19)(-0.15)+/-0.14) pb and infer sigma(e+e- -->J/psicc;)/sigma(e+e- -->J/psiX)=0.59(+0.15)(-0.13)+/-0.12. These results are obtained from a 46.2 fb(-1) data sample collected near the Upsilon(4S) resonance, with the Belle detector at the KEKB collider.

We report the first observation of the B-->Dmacr;D(sJ)(2317) and B-->Dmacr;D(sJ)(2457) decays based on 123.8x10(6) BBmacr; events collected with the Belle detector at KEKB. We observe the D(sJ)(2317) decay to D(s)pi(0) and the D(sJ)(2457) decay to the D(*)(s)pi(0) and D(s)gamma final states. We also set 90% C.L. upper limits for the decays D(sJ)(2317)-->D(*)(s)gamma, D(sJ)(2457)-->D(*)(s)gamma, D(sJ)(2457)-->D(s)pi(0), and D(sJ)(2457)-->D(s)pi(+)pi(-).

We report a fully inclusive measurement of the flavor changing neutral current decay b --> sgamma in the energy range 1.8 GeV < or = E*gamma < or = 2.8 GeV, covering 95% of the total spectrum. Using 140 fb(-1), we obtain B(b --> sgamma) = (3.55+/-0.32(+0.30+0.11)(-0.31-0.07)) x 10(-4), where the errors are statistical, systematic, and from theory corrections. We also measure the first and second moments of the photon energy spectrum above 1.8 GeV and obtain (Egamma) = 2.292+/-0.026+/-0.034 GeV and (E2gamma) - (Egamma)2 = 0.0305+/-0.0074+/-0.0063 GeV2, where the errors are statistical and systematic.

We report the first observation of a near-threshold enhancement in the D(0)D[over](0)pi(0) system from B-->D(0)D[over](0)pi(0)Kappa decays using a 414 fb(-1) data sample collected at the Upsilon(4S) resonance. The enhancement peaks at a mass M=3875.2+/-0.7(+0.3)/(-1.6) +/-0.8 MeV/c2 and the branching fraction for events in the peak is B(B-->D(0)D[over](0)pi(0)Kappa)=(1.22+/-0.31(+0.23)/(-0.30))x10(-4). The data were collected with the Belle detector at the KEKB energy-asymmetric e+ e- collider.

The upcoming 50 kt magnetized iron calorimeter (ICAL) detector at the India-based Neutrino Observatory (INO) is designed to study the atmospheric neutrinos and antineutrinos separately over a wide range of energies and path lengths. The primary focus of this experiment is to explore the Earth matter effects by observing the energy and zenith angle dependence of the atmospheric neutrinos in the multi-GeV range. This study will be crucial to address some of the outstanding issues in neutrino oscillation physics, including the fundamental issue of neutrino mass hierarchy. In this document, we present the physics potential of the detector as obtained from realistic detector simulations. We describe the simulation framework, the neutrino interactions in the detector, and the expected response of the detector to particles traversing it. The ICAL detector can determine the energy and direction of the muons to a high precision, and in addition, its sensitivity to multi-GeV hadrons increases its physics reach substantially. Its charge identification capability, and hence its ability to distinguish neutrinos from antineutrinos, makes it an efficient detector for determining the neutrino mass hierarchy. In this report, we outline the analyses carried out for the determination of neutrino mass hierarchy and precision measurements of atmospheric neutrino mixing parameters at ICAL, and give the expected physics reach of the detector with 10 years of runtime. We also explore the potential of ICAL for probing new physics scenarios like CPT violation and the presence of magnetic monopoles.

We present the first measurement of the D*+ width using 9/fb of e+ e- data collected near the Upsilon(4S) resonance by the CLEO II.V detector. Our method uses advanced tracking techniques and a reconstruction method that takes advantage of the small vertical size of the CESR beam spot to measure the energy release distribution from the D*+ -> D0 pi+ decay. We find Gamma(D*+) = 96 +- 4 (Statistical) +- 22 (Systematic) keV. We also measure the energy release in the decay and compute Delta m = m(D*+) - m(D0) = 145.412 +- 0.002 (Statistical) +- 0.012 (Systematic) MeV/c^2

We report the observation of a narrow peak in the K(S)K-pi(+) invariant mass distribution in a sample of exclusive B-->KK(S)K-pi(+) decays collected with the Belle detector at the KEKB asymmetric e(+)e(-) collider. The measured mass of the peak is M=3654+/-6(stat)+/-8(syst) MeV/c(2), and we place a 90% confidence level upper limit on the width of Gamma<55 MeV/c(2). The properties agree with heavy-quark potential model expectations for the eta(c)(2S) meson, the n=2 singlet S charmonium state.

We report results on the Dalitz analysis of three-body charmless B + → K + π + π -and B + → K + K + K -decays based on a 140 fb -1 data sample collected with the Belle detector.Measurements of branching fractions for quasi-two-body decays to scalar-pseudoscalar states: B + → f 0 (980)K + , B + → K * 0 (1430) 0 π + , and to vector-pseudoscalar states:Upper limits on decays to some pseudoscalar-tensor final states are reported.We also report the measurement of the B + → χ c0 K + branching fraction in two χ c0 decays channels: χ c0 → π + π -and χ c0 → K + K -.

We present an improved measurement of the branching fraction for the electroweak penguin process B-&gt;Xsll, where l is an electron or a muon and Xs is a hadronic system containing an s-quark. The measurement is based on a sample of 152*10^6 Upsilon(4S) -&gt; BB events collected with the Belle detector at the KEKB energy asymmetric e+e- collider. The Xs hadronic system is reconstructed from one K^{+-} or K^{0}_{S} and up to four pions, where at most one pion can be neutral. Averaging over both lepton flavors, the inclusive branching fraction is measured to be Br(B-&gt;Xsll)=(4.11+-0.83(stat)+0.85-0.81(syst))*10^{-6} for M_ll &gt; 0.2GeV/c2.

We have studied exclusive, radiative B meson decays to charmless mesons in 9.7x10(6) B&Bmacr; decays accumulated with the CLEO detector. We measure B(B0-->K(*0)(892)gamma) = (4.55(+0.72)(-0. 68)+/-0.34)x10(-5) and B(B+-->K(*+)(892)gamma) = (3.76(+0.89)(-0. 83)+/-0.28)x10(-5). We have searched for CP asymmetry in B-->K(*)(892)gamma decays and measure A(CP) = +0.08+/-0.13+/-0.03. We report the first observation of B-->K(*)(2)(1430)gamma decays with a branching fraction of (1.66(+0.59)(-0.53)+/-0.13)x10(-5). No evidence for the decays B-->rhogamma and B0-->omegagamma is found and we limit B(B-->(rho/omega)gamma)/B(B-->K(*)(892)gamma)<0.32 at 90% C.L.

We present a new analysis of double charmonium production in e + e -annihilation.The observation of the processes e + e -→ J/ψ ηc, J/ψ χc0, and J/ψ ηc(2S) is confirmed using a dataset more than three times larger than that of Belle's previous report, and no evidence for the process e + e -→ J/ψ J/ψ is found.We perform an angular analysis for J/ψ ηc production and set an upper limit on the production of J/ψ J/ψ.Processes of the type e + e -→ ψ(2S)(cc)res have been observed for the first time; their rates are found to be comparable to those of e + e -→ J/ψ(cc)res processes.

We report on a study of the invariant mass spectrum of the hadronic system in the decay τ−→π−π0ντ. This study was performed with data obtained with the CLEO II detector operating at the CESR e+e− collider. We present fits to phenomenological models in which resonance parameters associated with the ρ(770) and ρ(1450) mesons are determined. The π−π0 spectral function inferred from the invariant mass spectrum is compared with data on e+e−→π+π− as a test of the conserved vector current theorem. We also discuss the implications of our data with regard to estimates of the hadronic contribution to the muon anomalous magnetic moment.Received 21 October 1999DOI:https://doi.org/10.1103/PhysRevD.61.112002©2000 American Physical Society

We report measurements of the properties of the D(+)(sJ)(2317) and D(+)(sJ)(2457) resonances produced in continuum e(+)e(-) annihilation near sqrt[s]=10.6 GeV. The analysis is based on an 86.9 fb(-1) data sample collected with the Belle detector at KEKB. We determine the masses to be M(D(+)(sJ)(2317))=2317.2+/-0.5(stat)+/-0.9(syst) MeV/c(2) and M(D(+)(sJ)(2457))=2456.5+/-1.3(stat)+/-1.3(syst) MeV/c(2). We observe the radiative decay mode D(+)(sJ)(2457)-->D(+)(s)gamma and the dipion decay mode D(+)(sJ)(2457)-->D(+)(s)pi(+)pi(-) and determine their branching fractions. No corresponding decays are observed for the D(sJ)(2317) state. These results are consistent with the spin-parity assignments of 0(+) for the D(sJ)(2317) and 1(+) for the D(sJ)(2457).

We report a measurement of the exclusive e+e−→D(*)±D*∓ cross section as a function of center-of-mass energy near the D(*)±D*∓ threshold with initial-state radiation. A partial reconstruction technique is used to increase the efficiency and to suppress background. The analysis is based on a data sample collected with the Belle detector with an integrated luminosity of 547.8 fb−1.Received 12 January 2007DOI:https://doi.org/10.1103/PhysRevLett.98.092001©2007 American Physical Society

We present the first measurement of the D*(+) width using 9/fb of e(+)e(-) data collected near the Upsilon(4S) resonance by the CLEO II.V detector. Our method uses advanced tracking techniques and a reconstruction method that takes advantage of the small vertical size of the Cornell Electron-positron Storage Ring beam spot to measure the energy release distribution from the D*(+)-->D(0)pi(+) decay. We find gamma(D*(+)) = 96+/-4 (stat)+/-22 (syst) keV. We also measure the energy release in the decay and compute Delta m identical with m(D*(+))-m(D(0)) = 145.412+/-0.002 (stat)+/-0.012 (syst) MeV/c(2).

Using 13.7 fb^{-1} of data recorded by the CLEO detector at CESR, we investigate the spectrum of charmed baryons which decay into Lambda_c^+ pi^- pi^+ and are more massive than the Lambda_{c1} baryons. We find evidence for two new states: one is broad and has an invariant mass roughly 480 MeV above that of the Lambda_c^+; the other is narrow with an invariant mass of 596 +- 1 +- 2 MeV above the Lambda_c^+ mass. These results are preliminary.

We describe the design, construction and performance of a Ring Imaging Cherenkov Detector (RICH) constructed to identify charged particles in the CLEO experiment. Cherenkov radiation occurs in LiF crystals, both planar and ones with a novel “sawtooth”-shaped exit surface. Photons in the wavelength interval 135–165 nm are detected using multi-wire chambers filled with a mixture of methane gas and triethylamine vapor. Excellent π/K separation is demonstrated.

We briefly describe the design, construction and performance of the LiF-Tea RICH detector built to identify charged particles in the CLEO III experiment. Excellent pion/kaon separation is demonstrated.

The B meson decay modes B --> D p pbar and B --> D* p pbar have been studied using 29.4 fb^{-1} of data collected with the Belle detector at KEKB. The B0bar --> D0 p pbar and B0bar --> D*0 p pbar decays have been observed for the first time with branching fractions Br(B0bar --> D0 p pbar) =(1.18\pm 0.15\pm 0.16) 10^{-4} and Br(B0bar --> D*0 p pbar) =(1.20^{+0.33}_{-0.29}\pm 0.21) 10^{-4}. No signal has been found for the B+ --> D+ p pbar and B+ --> D*+ p pbar decay modes, and the corresponding upper limits at 90% C.L. are presented.

In a sample of 19 million produced B mesons, we have observed the decays B -> eta K* and improved our previous measurements of B -> eta'K. The branching fractions we measure for these decay modes are BR(B+ -> eta K*+) = (26.4 +9.6-8.2 +- 3.3) x $10^{-6}$, BR(B0 -> eta K*0) = (13.8 +5.5-4.6 +- 1.6) x $10^{-6}$, BR(B+ -> eta' K+) = (80 +10-9 +- 7) x $10^{-6}$ and BR(B0 -> eta' K0) = (89 +18-16 +- 9) x $10^{-6}$. We have searched with comparable sensitivity for related decays and report upper limits for these branching fractions.

We report the first observation of the charmless vector-vector decay process B∓→ρ∓ρ0. The measurement uses a 78 fb−1 data sample collected with the Belle detector at the KEKB asymmetric e+e− collider operating at the Υ(4S) resonance. We obtain a branching fraction of B(B∓→ρ∓ρ0)=[31.7±7.1(stat)−6.7+3.8(syst)]×10−6. An analysis of the ρ helicity-angle distributions gives a longitudinal polarization fraction of ΓL/Γ=0.95±0.11(stat)±0.02(syst). We also measure the direct-CP-violating asymmetry ACP(B∓→ρ∓ρ0)=0.00±0.22(stat)±0.03(syst).Received 3 June 2003DOI:https://doi.org/10.1103/PhysRevLett.91.221801©2003 American Physical Society

We report measurements of the radiative decay B → K * γ.The analysis is based on a data sample containing 85.0 × 10 6 B meson pairs collected by the Belle detector at the KEKB storage ring.We measure branching fractions of B(B 0 → K * 0 γ) = (4.01 ± 0.21 ± 0.17) × 10 -5 and B(B + → K * + γ) = (4.25 ± 0.31 ± 0.24) × 10 -5 , where the first and second errors are statistical and systematic, respectively.The isospin asymmetry between B 0 and B + decay widths is measured to be ∆0+ = +0.012± 0.044 ± 0.026.We search for a partial rate asymmetry between CP conjugate modes, and find ACP (B → K * γ) = -0.015± 0.044 ± 0.012.

Using a 282 1/fb data sample collected by the Belle experiment at the KEKB e+e- collider, we study D0 decays to K-l+nu and pi-l+nu final states. The D0 flavor and momentum are tagged through a full reconstruction of the recoiling charm meson and additional mesons from fragmentation. The reconstruction method provides very good resolution in neutrino momentum and in q^2 = (p_l+p_nu)^2. Normalizing to the total number of D0 tags, we measure the absolute branching fractions to be B(D0 -> Klnu) =(3.45 +- 0.07stat +- 0.20syst)% and B(D0 -> pilnu) = (0.255 +- 0.019stat +- 0.016syst)% and the semi-leptonic form factors (within the modified pole model) f+^K(0) = 0.695 +- 0.007stat +- 0.022syst and f+^pi(0) = 0.624 +- 0.020stat +- 0.030syst.

We report the results of several studies of the Lambda(c)(+)pi(+)pi(-)X final state in continuum e(+)e(-) annihilation data collected by the Belle detector. An analysis of angular distributions in Lambda(c)(2880)(+)-->Sigma(c)(2455)(0,++)pi(+,-) decays strongly favors a Lambda(c)(2880)(+) spin assignment of 5/2 over 3/2 or 1/2. We find evidence for Lambda(c)(2880)(+)-->Sigma(c)(2520)(0,++)pi(+,-) decay and measure the ratio of Lambda(c)(2880)(+) partial widths Gamma(Sigma(c)(2520)pi)/Gamma(Sigma(c)(2455)pi)=0.225+/-0.062+/-0.025. This value favors the Lambda(c)(2880)(+) spin-parity assignment of 5/2(+) over 5/2(-). We also report the first observation of Lambda(c)(2940)(+)-->Sigma(c)(2455)(0,++)pi(+,-) decay and measure Lambda(c)(2880)(+) and Lambda(c)(2940)(+) mass and width parameters. These studies are based on a 553 fb(-1) data sample collected at or near the Upsilon(4S) resonance at the KEKB collider.

We present a precise measurement of the standard model $CP$-violation parameter $\mathrm{sin}2{\ensuremath{\phi}}_{1}$, the direct $CP$ violation parameter $|\ensuremath{\lambda}|$, the lifetimes of charged and neutral $B$ mesons and their ratio, and the ${B}^{0}$-${\overline{B}}^{0}$ mixing parameter $\ensuremath{\Delta}{m}_{d}$ based on a sample of $152\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $B\overline{B}$ pairs collected at the $\ensuremath{\Upsilon}(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy ${e}^{+}{e}^{\ensuremath{-}}$ collider. One of two $B$ mesons is fully reconstructed in a $CP$-eigenstate or a flavor-eigenstate decay channel. The flavor of the accompanying $B$ meson is identified from its decay products. From the distributions of the time interval between the two $B$ meson decay points, we obtain $\mathrm{sin}2{\ensuremath{\phi}}_{1}=0.728\ifmmode\pm\else\textpm\fi{}0.056(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.023(\mathrm{syst})$, $|\ensuremath{\lambda}|=1.007\ifmmode\pm\else\textpm\fi{}0.041(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.033(\mathrm{syst})$, ${\ensuremath{\tau}}_{{B}^{0}}=[1.534\ifmmode\pm\else\textpm\fi{}0.008(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.010(\mathrm{syst})]\text{ }\text{ }\mathrm{ps}$, ${\ensuremath{\tau}}_{{B}^{+}}=[1.635\ifmmode\pm\else\textpm\fi{}0.011(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.011(\mathrm{syst})]\text{ }\text{ }\mathrm{ps}$, ${\ensuremath{\tau}}_{{B}^{+}}/{\ensuremath{\tau}}_{{B}^{0}}=1.066\ifmmode\pm\else\textpm\fi{}0.008(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.008(\mathrm{syst})$ and $\ensuremath{\Delta}{m}_{d}=[0.511\ifmmode\pm\else\textpm\fi{}0.005(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.006{(\mathrm{syst})]\text{ }\text{ }\mathrm{ps}}^{\ensuremath{-}1}$. The results for $\mathrm{sin}2{\ensuremath{\phi}}_{1}$ and $|\ensuremath{\lambda}|$ are consistent with the standard model expectations. The significance of the observed deviation from unity in the lifetime ratio exceeds 5 standard deviations.

We report the first measurement of the forward-backward asymmetry and the ratios of Wilson coefficients A 9 /A 7 and A 10 /A 7 in B → K * ℓ + ℓ -, where ℓ represents an electron or a muon.We observe a large integrated forward-backward asymmetry with a significance of 3.4σ.The results are obtained from a data sample containing 386 ×10 6 B B pairs that were collected on the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e + e -collider.

We search for CP-violating charge asymmetries (alpha(CP)) in the B meson decays to K(+/-)pi(-/+), K(+/-)pi(0), K(0)(S)pi(+/-), K(+/-)eta('), and omega pi(+/-). Using 9.66 million upsilon(4S) decays collected with the CLEO detector, the statistical precision on alpha(CP) is in the range of +/-0.12 to +/-0.25 depending on decay mode. While CP-violating asymmetries of up to +/-0.5 are possible within the standard model, the measured asymmetries are consistent with zero in all five decay modes studied.

We report results of searches for charmless hadronic B meson decays to pseudoscalar( pi(+/-), K+/-, pi(0), or K(0)(S))-vector( rho, K(*), or omega) final states. By using 9.7x10(6) BB pairs collected with the CLEO detector, we report the first observation of B(-)--->pi(-)rho(0), B(0)-->pi(+/-)rho(-/+), and B(-)-->pi(-)omega, which are expected to be dominated by hadronic b-->u transitions. The measured branching fractions are (10.4(+3.3)(-3.4)+/-2.1)x10(-6), (27.6(+8.4)(-7.4)+/-4.2)x10(-6), and (11.3(+3.3)(-2.9)+/-1. 4)x10(-6), respectively. Branching fraction upper limits are set for all of the other decay modes investigated.

We have studied charmless hadronic decays of $B$ mesons into two-body final states with kaons and pions and observe three new processes with the following branching fractions: $B(B\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}})\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}({4.3}_{\ensuremath{-}1.4}^{+1.6}\ifmmode\pm\else\textpm\fi{}0.5)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$, $B(B\ensuremath{\rightarrow}{K}^{0}{\ensuremath{\pi}}^{0})\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}({14.6}_{\ensuremath{-}5.1\ensuremath{-}3.3}^{+5.9+2.4})\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$, and $B(B\ensuremath{\rightarrow}{K}^{\ifmmode\pm\else\textpm\fi{}}{\ensuremath{\pi}}^{0})\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}({11.6}_{\ensuremath{-}2.7\ensuremath{-}1.3}^{+3.0+1.4})\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$. We also update our previous measurements for the decays $B\ensuremath{\rightarrow}{K}^{\ifmmode\pm\else\textpm\fi{}}{\ensuremath{\pi}}^{\ensuremath{\mp}}$ and ${B}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\rightarrow}{K}^{0}{\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}$.

We report the observation of the flavor-changing neutral current decay B-->K(*)l(+)l(-) and an im-proved measurement of the decay B-->Kl(+)l(-), where l represents an electron or a muon, with a data sample of 140 fb(-1) accumulated at the Upsilon(4S) resonance with the Belle detector at KEKB. The results for the branching fractions are B(B-->K(*)l(+)l(-))=(11.5(+2.6)(-2.4)+/-0.8+/-0.2)x10(-7) and B(B-->Kl(+)l(-))=(4.8(+1.0)(-0.9)+/-0.3+/-0.1)x10(-7), where the first error is statistical, the second is systematic and the third is from model dependence.

We have measured the first and second moments of the hadronic mass-squared distribution in B -> X_c l nu, for P(lepton) > 1.5 GeV/c. We find <M_X^2 - M_D[Bar]^2> = 0.251 +- 0.066 GeV^2, < (M_X^2 -<M_X^2>)^2 > = 0.576 +- 0.170 GeV^4, where M_D[Bar] is the spin-averaged D meson mass. From that first moment and the first moment of the photon energy spectrum in b -> s gamma, we find the HQET parameter lambda_1 (MS[Bar], to order 1/M^3 and beta_0 alpha_s^2) to be -0.24 +- 0.11 GeV^2. Using these first moments and the B semileptonic width, and assuming parton-hadron duality, we obtain |V_cb| = 0.0404 +- 0.0013.

We report the first observation of a b -> u type charmless baryonic B decay, B+ -> p pbar pi+, as well as b -> s type B0 -> p pbar K0 and B+ -> p pbar K*+ decays. The analysis is based on a 78fb^{-1} data sample recorded on the Upsilon(4S) resonance with the Belle detector at KEKB. We find BF(B+ -> p pbar pi+) = (3.06^{+0.73}_{-0.62} \pm 0.37)*10^{-6}, BF(B0 -> p pbar K0) =(1.88^{+0.77}_{-0.60} \pm 0.23)*10^{-6}, and BF(B+ -> p pbar K*+) = (10.3^{+3.6 + 1.3}_{-2.8 -1.7})*10^{-6}. We also update BF(B+ -> p pbar K+) = (5.66^{+0.67}_{-0.57} \pm 0.62)* 10^{-6}, and present an upper limit on BF(B0 -> p pbar K*0) at the 90% confidence level. A common feature of the observed decay modes is threshold peaking in baryon pair invariant mass.

We present a measurement of the unitarity triangle angle ${\ensuremath{\phi}}_{3}$ using a Dalitz plot analysis of the ${K}_{S}^{0}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ decay of the neutral $D$ meson from the ${B}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\rightarrow}{D}^{(*)}{K}^{(*)\ifmmode\pm\else\textpm\fi{}}$ process. The method exploits the interference between ${D}^{0}$ and ${\overline{D}}^{0}$ to extract the angle ${\ensuremath{\phi}}_{3}$, strong phase $\ensuremath{\delta}$ and the ratio $r$ of suppressed and allowed amplitudes. We apply this method to a $357\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ data sample collected by the Belle experiment. The analysis uses three modes: ${B}^{+}\ensuremath{\rightarrow}D{K}^{+}$, ${B}^{+}\ensuremath{\rightarrow}{D}^{*}{K}^{+}$ with ${D}^{*}\ensuremath{\rightarrow}D{\ensuremath{\pi}}^{0}$, and ${B}^{+}\ensuremath{\rightarrow}D{K}^{*+}$ with ${K}^{*+}\ensuremath{\rightarrow}{K}_{S}^{0}{\ensuremath{\pi}}^{+}$, as well as the corresponding charge-conjugate modes. From a combined maximum likelihood fit to the three modes, we obtain ${\ensuremath{\phi}}_{3}=53\ifmmode^\circ\else\textdegree\fi{}\genfrac{}{}{0}{}{+15\ifmmode^\circ\else\textdegree\fi{}}{\ensuremath{-}18\ifmmode^\circ\else\textdegree\fi{}}(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}3\ifmmode^\circ\else\textdegree\fi{}(\mathrm{syst})\ifmmode\pm\else\textpm\fi{}9\ifmmode^\circ\else\textdegree\fi{}(\mathrm{\text{model}})$. The corresponding 2 standard deviation interval is $8\ifmmode^\circ\else\textdegree\fi{}&lt;{\ensuremath{\phi}}_{3}&lt;111\ifmmode^\circ\else\textdegree\fi{}$.

We present new measurements of CP-violation parameters in B0 -&gt; phiK0, K+K-Ks, f0(980)Ks, eta'Ks, omegaKs and Kspi0 decays based on a sample of 275 x 10^6 BBbar pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB energy-asymmetric e+e- collider. One neutral B meson is fully reconstructed in one of the specified decay channels, and the flavor of the accompanying B meson is identified from its decay products. CP-violation parameters for each of the decay modes are obtained from the asymmetries in the distributions of the proper-time intervals between the two B decays. The combined result for the B0-&gt;phiK0, K+K-Ks, f0(980)Ks, eta'Ks, omegaKs, Kspi0, and previously reported KsKsKs decays differs from the SM expectation by 2.4 standard deviations.

The resonant structure of the four pion final state in the decay $\stackrel{\ensuremath{\rightarrow}}{\ensuremath{\tau}}3\ensuremath{\pi}{\ensuremath{\pi}}^{0}{\ensuremath{\nu}}_{\ensuremath{\tau}}$ has been analyzed using 4.27 million ${\ensuremath{\tau}}^{+}{\ensuremath{\tau}}^{\ensuremath{-}}$ pairs collected by the CLEO II experiment at the Cornell Electron Storage Ring. A partial wave analysis of the resonant structure of the $\stackrel{\ensuremath{\rightarrow}}{\ensuremath{\tau}}3\ensuremath{\pi}{\ensuremath{\pi}}^{0}{\ensuremath{\nu}}_{\ensuremath{\tau}}$ decay has been performed; the spectral decomposition of the four pion system is dominated by the $\ensuremath{\omega}\ensuremath{\pi}$ and ${a}_{1}\ensuremath{\pi}$ final states. The mass and width of the ${\ensuremath{\rho}}^{\ensuremath{'}}$ resonance have been extracted from a fit to the $\stackrel{\ensuremath{\rightarrow}}{\ensuremath{\tau}}\ensuremath{\omega}\ensuremath{\pi}{\ensuremath{\nu}}_{\ensuremath{\tau}}$ spectral function. We have searched for second class currents in the decay $\stackrel{\ensuremath{\rightarrow}}{\ensuremath{\tau}}\ensuremath{\omega}\ensuremath{\pi}{\ensuremath{\nu}}_{\ensuremath{\tau}}$ using spin-parity analysis and established an upper limit on the non-vector current contribution.

We report the first observation of the charmless hyperonic B decay, B0-->pLambda(pi)(-), using a 78 fb(-1) data sample recorded on the Upsilon(4S) resonance with the Belle detector at KEKB. The measured branching fraction is B(B0-->pLambda(pi)(-))=(3.97(+1.00)(-0.80)+/-0.56)x10(-6). Searches for B0-->pLambda(K)- and pSigma(0)pi(-) yield no significant signals and we set 90% confidence-level upper limits of B(B0-->pLambda(K)-)<8.2x10(-7) and B(B0-->pSigma(0)pi(-))<3.8x10(-6).

We report results of a study of charmless B meson decays to three-body Kππ,KKπ and KKK final states. Measurements of branching fractions for B decays to K+(0)π+π−,K+K+K−,K0K+K−,K+K0SK0S and K0SK0SK0S final states are presented. The decays B0→K0K+K−,B+→K+K0SK0S and B0→K0SK0SK0S are observed for the first time. We also report evidence for B+→K+K−π+ decay. For the three-body final states K0K+π−,K0SK0Sπ+,K+K+π− and K−π+π+, 90% confidence level upper limits are reported. Finally, we discuss the possibility of using the three-body B0→K0SK+K− decay for CP violation studies. The results are obtained with a 78 fb−1 data sample collected at the Υ(4S) resonance by the Belle detector operating at the KEKB asymmetric energy e+e− collider.Received 1 August 2003DOI:https://doi.org/10.1103/PhysRevD.69.012001©2004 American Physical Society

This report provides a comprehensive overview of the prospects for B physics at the Tevatron. The work was carried out during a series of workshops starting in September 1999. There were four working groups: 1) CP Violation, 2) Rare and Semileptonic Decays, 3) Mixing and Lifetimes, 4) Production, Fragmentation and Spectroscopy. The report also includes introductory chapters on theoretical and experimental tools emphasizing aspects of B physics specific to hadron colliders, as well as overviews of the CDF, D0, and BTeV detectors, and a Summary.

We present an update of the search for the lepton family number violating decay $\stackrel{\ensuremath{\rightarrow}}{\ensuremath{\tau}}\ensuremath{\mu}\ensuremath{\gamma}$ using 12.6 million ${\ensuremath{\tau}}^{+}{\ensuremath{\tau}}^{\ensuremath{-}}$ pairs collected with the CLEO detector. No evidence of a signal has been found and the corresponding upper limit is $\mathcal{B}(\stackrel{\ensuremath{\rightarrow}}{\ensuremath{\tau}}\ensuremath{\mu}\ensuremath{\gamma})&lt;1.1\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$ at 90% C.L., significantly smaller than previous experimental limits.

CP violation in B → J/ψK * decays is studied using an angular analysis in a data sample of 253 fb -1 recorded with the Belle detector at the KEKB e + e -collider.The flavor separated measurements of the decay amplitudes indicate no evidence for direct CP violation.T-odd CP violation is studied using the asymmetries in triple product correlations, and the results are consistent with the Standard Model null predictions.The time-dependent angular analysis gives the following values of CP-violating parameters: sin 2φ 1 = 0.24 ± 0.31 ± 0.05 and cos 2φ 1 = 0.56 ± 0.79 ± 0.11.

In a sample of 9.66x10(6)B&Bmacr; pairs collected with the CLEO detector we make the first observation of B decays to an eta(c) and a kaon. We measure branching fractions B(B+-->eta(c)K+) = (0.69(+0.26)(-0.21)+/-0.08+/-0.20)x10(-3) and B(B degrees -->eta(c)K degrees ) = (1.09(+0.55)(-0.42)+/-0.12+/-0.31)x10(-3), where the first error is statistical, the second is systematic, and the third is from the eta(c) branching fraction uncertainty. From these we extract the eta(c) decay constant in the factorization approximation, f(eta(c)) = 335+/-75 MeV. We also search for B decays to a chi(c0) and a kaon. No evidence for a signal is found and we set 90% C.L. upper limits: B(B+-->chi(c0)K+)<4.8x10(-4) and B(B degrees -->chi(c0)K degrees )<5.0x10(-4).

We report the first measurement of the branching fraction for the inclusive decay B-->X(s)l(+)l(-), where l is either an electron or a muon, and X(s) is a hadronic recoil system that contains an s quark. We analyzed a data sample of 65.4 x 10(6) B meson pairs collected with the Belle detector at the KEKB e(+)e(-) asymmetric-energy collider. We find B(B-->X(s)l(+)l(-))=[6.1 +/-1.4(stat) +1.4-1.1(syst)] x 10(-6) for dilepton masses greater than 0.2 GeV/c(2).

We report the observation of the radiative decay B+ --> K1(1270)+ gamma using a data sample of 140 fb-1 taken at the Upsilon(4S) resonance with the Belle detector at the KEKB e+e- collider. We find the branching fraction to be Br(B+ --> K1(1270)+ gamma) = (4.3 +- 0.9(stat.) +- 0.9(syst.)) x 10-5 with a statistical significance of 7.3sigma. We find no significant signal for B+ --> K1(1400)+ gamma and set an upper limit Br(B+ --> K1(1400)+ gamma) < 1.5 x 10-5 at the 90% confidence level. We also measure inclusive branching fractions for B+ --> K+ pi+ pi- gamma and B0 --> K0 pi+ pi- gamma in the mass range 1 GeV/c^2 < M(K+(0)pi+pi-) < 2 GeV/c^2.

We have measured π+π− and K+K− production in two-photon collisions using 87.7fb−1 of data collected with the Belle detector at the asymmetric energy e+e− collider KEKB. The cross sections are measured to high precision in the two-photon center-of-mass energy (W) range between 2.4GeV<W<4.1GeV and angular region |cosθ∗|<0.6. The cross section ratio σ(γγ→K+K−)/σ(γγ→π+π−) is measured to be 0.89±0.04(stat.)±0.15(syst.) in the range of 3.0GeV<W<4.1GeV, where the ratio is energy-independent. We observe a sin−4θ∗ behavior of the cross section in the same W range. Production of χc0 and χc2 mesons is observed in both γγ→π+π− and γγ→K+K− modes.

We report measurements of the charmless semileptonic decays $B^0 \to \pi^- / \rho^- \ell^{+} \nu$ and $B^+ \to \pi^0 / \rho^0 \ell^{+} \nu$, based on a sample of $2.75 \times 10^8$ $B \bar{B}$ events collected at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB $e^+e^-$ asymmetric collider. In this analysis, the accompanying $B$ meson is reconstructed in the semileptonic mode $B \to D^{(*)} \ell \nu$, enabling detection of the signal modes with high purity. We measure the branching fractions ${\mathcal B}(B^0 \to \pi^- \ell^+ \nu) = (1.38\pm 0.19\pm 0.14\pm 0.03) \times 10^{-4}$, ${\mathcal B}(B^0 \to \rho^- \ell^+ \nu) = (2.17\pm 0.54\pm 0.31\pm 0.08) \times 10^{-4}$, ${\mathcal B}(B^+ \to \pi^0 \ell^+ \nu) = (0.77\pm 0.14\pm 0.08\pm 0.00) \times 10^{-4}$ and ${\mathcal B}(B^+ \to \rho^0 \ell^+ \nu) = (1.33\pm 0.23\pm 0.17\pm 0.05) \times 10^{-4}$, where the errors are statistical, experimental systematic, and systematic due to form-factor uncertainties, respectively. For each mode we also present the partial branching fractions in three $q^2$ intervals: $q^2 < 8$, $8 \leq q^2 < 16$, and $q^2 \geq 16$ GeV$^2/c^2$. From our partial branching fractions for $B \to \pi \ell \nu$ and recent results for the form factor from unquenched Lattice QCD calculations, we obtain values of the CKM matrix element $|V_{ub}|$.

We report results of a Dalitz plot analysis of the three-body charmless B 0 → K 0 π + π -decay.The analysis is performed with a data sample that contains 388 million B B pairs collected near the Υ(4S) resonance with the Belle detector at the KEKB asymmetric energy e + e -collider.Measurements of branching fractions for the quasi-two-body decays B 0 → ρ(770) 0 K 0 , B 0 → f0(980)K 0 , B 0 → K * (892) + π -, B 0 → K * (1430) + π -, and upper limits on several other quasi-two-body decay modes are reported.

We report the first observation of the charmless hyperonic $B$ decay, ${B}^{+}\ensuremath{\rightarrow}\ensuremath{\Lambda}\overline{\ensuremath{\Lambda}}{K}^{+}$, using a $140\text{ }{\mathrm{f}\mathrm{b}}^{\ensuremath{-}1}$ data sample recorded at the $\ensuremath{\Upsilon}(4\mathrm{S})$ resonance with the Belle detector at the KEKB ${e}^{+}{e}^{\ensuremath{-}}$ collider. The measured branching fraction is $\mathcal{B}({B}^{+}\ensuremath{\rightarrow}\ensuremath{\Lambda}\overline{\ensuremath{\Lambda}}{K}^{+})=({2.91}_{\ensuremath{-}0.70}^{+0.90}\ifmmode\pm\else\textpm\fi{}0.38)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$. We also perform a search for the related decay mode ${B}^{+}\ensuremath{\rightarrow}\ensuremath{\Lambda}\overline{\ensuremath{\Lambda}}{\ensuremath{\pi}}^{+}$, but do not find a significant signal. We set a 90% confidence-level upper limit of $\mathcal{B}({B}^{+}\ensuremath{\rightarrow}\ensuremath{\Lambda}\overline{\ensuremath{\Lambda}}{\ensuremath{\pi}}^{+})&lt;2.8\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$.

The branching fractions and the decay amplitudes of B→J/ψK∗ decays are measured in a 29.4 fb−1 data sample collected with the Belle detector at the KEKB electron–positron collider. The decay amplitudes of helicity states of the J/ψK∗ system are determined from the full angular distribution of the final state particles in the transversity basis. The branching fractions are measured to be (1.29±0.05±0.13)×10−3 for neutral mesons and (1.28±0.07±0.14)×10−3 for charged mesons. The measured longitudinal and transverse (perpendicular to the transversity plane) amplitudes are |A0|2=0.62±0.02±0.03 and |A⊥|2=0.19±0.02±0.03, respectively. The value of |A⊥|2 shows that the CP even component dominates in the B0→J/ψK∗0(KSπ0) decay.

We have measured the CP asymmetry A(CP) identical with[gamma(b-->sgamma)-gammab-->sgamma)]/[gamma(b-->sgamma)+gamma(b-->sgamma)] to be A(CP) = (-0.079+/-0.108+/-0.022) (1.0+/-0.030), implying that, at 90% confidence level, A(CP) lies between -0.27 and +0.10. These limits rule out some extreme non-standard-model predictions, but are consistent with most, as well as with the standard model.

We report a measurement of the charge asymmetry for same-sign dileptons in $B^0$-$\bar{B}^0$ mixing, $A_{\rm sl}$. The data were collected with the Belle detector at KEKB. Using a data sample of 78 fb$^{-1}$ recorded at the $\Upsilon(4S)$ resonance and 9 fb$^{-1}$ recorded at an energy 60 MeV below the resonance, we measure $A_{\rm sl} = (-1.1 \pm 7.9(\text{stat}) \pm 7.0(\text{sys}))\times 10^{-3}$.

We report the observation of the flavor-changing neutral current process b --&gt; d gamma using a sample of 386*10^6 B meson pairs accumulated by the Belle detector at the KEKB e+ e- collider. We measure branching fractions for the exclusive modes B- --&gt; rho- gamma, B0bar --&gt; rho0 gammaand B0bar --&gt; omega gamma. Assuming that these three modes are related by isospin, we find Br(B --&gt; (rho,omega) gamma) = (1.32 +0.34-0.31(stat.) +0.10-0.09(syst.)) * 10^-6 with a significance of 5.1 sigma. This result is used to determine the ratio of CKM matrix elements |V_td/V_ts| to be 0.199 +0.026-0.025(exp.) +0.018-0.015(theo.).

We report a measurement of the inclusive electron energy spectrum for charmed semileptonic decays of $B$ mesons in a $140\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ data sample collected at the $\ensuremath{\Upsilon}(4S)$ resonance with the Belle detector at the KEKB asymmetric energy ${e}^{+}{e}^{\ensuremath{-}}$ collider. We determine the first four moments of the electron energy spectrum for threshold values of the electron energy between 0.4 and 2.0 GeV. In addition, we provide values of the partial branching fraction (zeroth moment) for the same electron threshold energies, and independent measurements of the ${B}^{+}$ and ${B}^{0}$ partial branching fractions at 0.4 GeV and 0.6 GeV electron threshold energies. We measure the independent ${B}^{+}$ and ${B}^{0}$ partial branching fractions with electron threshold energies of 0.4 GeV to be $\ensuremath{\Delta}\mathcal{B}({B}^{+}\ensuremath{\rightarrow}{X}_{c}e\ensuremath{\nu})=(10.79\ifmmode\pm\else\textpm\fi{}0.25(\mathrm{stat}.)\ifmmode\pm\else\textpm\fi{}0.27(\mathrm{sys}.))%$ and $\ensuremath{\Delta}\mathcal{B}({B}^{0}\ensuremath{\rightarrow}{X}_{c}e\ensuremath{\nu})=(10.08\ifmmode\pm\else\textpm\fi{}0.30(\mathrm{stat}.)\ifmmode\pm\else\textpm\fi{}0.22(\mathrm{sys}.))%$. Full correlations between all measurements are evaluated.

We report the results of a study of neutral $B$ meson decays to the ${D}^{0}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ final state, where the ${D}^{0}$ is fully reconstructed. The results are obtained from an event sample containing $388\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $B\overline{B}$-meson pairs collected in the Belle experiment at the KEKB ${e}^{+}{e}^{\ensuremath{-}}$ collider. The total branching fraction of the three-body decay $\mathcal{B}({\overline{B}}^{0}\ensuremath{\rightarrow}{D}^{0}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}})=(8.4\ifmmode\pm\else\textpm\fi{}0.4(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.8(\mathrm{syst}))\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$ has been measured. The intermediate resonant structure of these three-body decays has been studied. From a Dalitz plot analysis we have obtained the product of the branching fractions for ${D}_{2}^{*+}$ and ${D}_{0}^{*+}$ production: $\mathcal{B}({\overline{B}}^{0}\ensuremath{\rightarrow}{D}_{2}^{*+}{\ensuremath{\pi}}^{\ensuremath{-}})\ifmmode\times\else\texttimes\fi{}\mathcal{B}({D}_{2}^{*+}\ensuremath{\rightarrow}{D}^{0}{\ensuremath{\pi}}^{+})=(2.15\ifmmode\pm\else\textpm\fi{}0.17(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.29(\mathrm{syst})\ifmmode\pm\else\textpm\fi{}0.12(\mathrm{mod}))\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$, and $\mathcal{B}({\overline{B}}^{0}\ensuremath{\rightarrow}{D}_{0}^{*+}{\ensuremath{\pi}}^{\ensuremath{-}})\ifmmode\times\else\texttimes\fi{}\mathcal{B}({D}_{0}^{*+}\ensuremath{\rightarrow}{D}^{0}{\ensuremath{\pi}}^{+})=(0.60\ifmmode\pm\else\textpm\fi{}0.13(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.15(\mathrm{syst})\ifmmode\pm\else\textpm\fi{}0.22(\mathrm{mod}))\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$. This is the first observation of the ${\overline{B}}^{0}\ensuremath{\rightarrow}{D}_{0}^{*+}{\ensuremath{\pi}}^{\ensuremath{-}}$ decay. The ${\overline{B}}^{0}\ensuremath{\rightarrow}{D}^{0}{\ensuremath{\rho}}^{0}$ and ${D}^{0}{f}_{2}$ branching fractions are measured to be: $\mathcal{B}({\overline{B}}^{0}\ensuremath{\rightarrow}{D}^{0}{\ensuremath{\rho}}^{0})=(3.19\ifmmode\pm\else\textpm\fi{}0.20(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.24(\mathrm{syst})\ifmmode\pm\else\textpm\fi{}0.38(\mathrm{mod}))\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$, and $\mathcal{B}({\overline{B}}^{0}\ensuremath{\rightarrow}{D}^{0}{f}_{2})=(1.20\ifmmode\pm\else\textpm\fi{}0.18(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.21(\mathrm{syst})\ifmmode\pm\else\textpm\fi{}0.32(\mathrm{mod}))\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$.

The inclusive production of $D_s$, $D^0$, and $J/\psi$ mesons is studied using a 1.86 fb$^{-1}$ data sample collected on the $\Upsilon$(5S) resonance by the Belle detector at the KEKB asymmetric energy $e^+ e^-$ collider. The number of $b\bar{b}$ events in the $\Upsilon$(5S) data sample is determined. We measure the branching fractions $B(\Upsilon({\rm 5S}) \to D_s X) / 2 = (23.6 \pm 1.2 \pm 3.6)%$, $B(\Upsilon({\rm 5S}) \to D^0 X) / 2 = (53.8 \pm 2.0 \pm 3.4)%$}, and $B(\Upsilon({\rm 5S}) \to J/\psi X) / 2 = (1.030 \pm 0.080 \pm 0.067)%$. From the $D_s$ and $D^0$ inclusive branching fractions the ratio $f_s = (18.0 \pm 1.3 \pm 3.2)%$} of $B_s^{(*)} \bar{B}_s^{(*)}$ to the total $b\bar{b}$ quark pair production at the $\Upsilon$(5S) energy is obtained in a model-dependent way.

We present a measurement of the hadronic invariant mass squared (${M}_{X}^{2}$) spectrum in charmed semileptonic $B$ meson decays $B\ensuremath{\rightarrow}{X}_{c}\ensuremath{\ell}\ensuremath{\nu}$ based on $140\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of Belle data collected near the $\ensuremath{\Upsilon}(4S)$ resonance. We determine the first, the second central, and the second noncentral moments of this spectrum for lepton energy thresholds ranging between 0.7 and 1.9 GeV. Full correlations between these measurements are evaluated.

The mass of the τ lepton has been measured in the decay mode τ→3πντ using a pseudomass technique. The result obtained from 414 fb−1 of data collected with the Belle detector is Mτ=[1776.61±0.13(stat)±0.35(sys)] MeV/c2. The upper limit on the relative mass difference between positive and negative τ leptons is |Mτ+−Mτ−|/Mτ<2.8×10−4 at 90% confidence level.Received 2 February 2007DOI:https://doi.org/10.1103/PhysRevLett.99.011801©2007 American Physical Society

A Kalman filter package has been developed for reconstructing muon (μ±) tracks (coming from the neutrino interactions) in ICAL detector. Here, we describe the algorithm of muon track fitting, with emphasis on the error propagation of the elements of Kalman state vector along the muon trajectory through dense materials and inhomogeneous magnetic field. The higher order correction terms are included for reconstructing muon tracks at large zenith angle θ (measured from the perpendicular to the detector planes). The performances of this algorithm and its limitations are discussed.

The 50 \,kton\, INO-ICAL is a proposed underground high energy physics experiment at Theni, India ($9^{\circ}57'N$, $77^{\circ}16'E$) to study the neutrino oscillation parameters using atmospheric neutrinos. The Resistive Plate Chamber (RPC) has been chosen as the active detector element for the ICAL detector. An experimental setup consisting of 12 layers of glass RPCs of size 2\,m\,$\times$\,2\,m has been built at IICHEP, Madurai to study the long term stability and performance of RPCs which are produced on a large scale in Indian industry. In this paper, the studies on the performance of RPCs are presented along with the angular distribution of muons at Madurai ($9^{\circ}56'N,78^{\circ}00'E$ and Altitude $\approx$\,160\,m from sea level).

The High Luminosity phase of the Large Hadron Collider will deliver 10 times more integrated luminosity than the existing collider, posing significant challenges for radiation tolerance and event pileup on detectors, especially for forward calorimetry. As part of its upgrade program, the Compact Muon Solenoid collaboration is designing a high-granularity calorimeter (HGCAL) to replace the existing endcap calorimeters. It will feature unprecedented transverse and longitudinal readout and triggering segmentation for both electromagnetic and hadronic sections. The electromagnetic section and a large fraction of the hadronic section will be based on hexagonal silicon sensors of 0.5–1 cm2 cell size, with the remainder of the hadronic section being based on highly-segmented scintillators with silicon photomultiplier readout. The intrinsic high-precision timing capabilities of the silicon sensors will add an extra dimension to event reconstruction, especially in terms of pileup rejection. First hexagonal silicon modules, using the existing Skiroc2 front-end ASIC developed for CALICE, have been tested in beams at Fermilab and CERN in 2016. We present results from these tests, in terms of system stability, calibration with minimum-ionizing particles and resolution (energy, position and timing) for electrons, and the comparisons of these quantities with GEANT4-based simulation.

We report observations of radiative B meson decays into the K+pi(-)gamma and K+pi(-)pi(+)gamma final states. In the B0-->K+pi(-)gamma channel, we present evidence for decays via an intermediate tensor meson state with a branching fraction of B(B0-->K(*)(2)(1430)(0)gamma)=[1.3+/-0.5(stat)+/-0.1(syst)]x10(-5). We measure the branching fraction B(B+-->K+pi(-)pi(+)gamma)=[2.4+/-0.5(stat) +0.4-0.2(syst)]x10(-5), in which the B+-->K(*0)pi(+)gamma and B+-->K+rho(0)gamma channels dominate. The analysis is based on a data set of 29.4 fb(-1) recorded by the Belle experiment at the KEKB collider.

Direct CP violation in the b→sγ process is a sensitive probe of physics beyond the standard model. We report a measurement of the CP asymmetry in B→Xsγ, where the hadronic recoil system Xs is reconstructed using a pseudoreconstruction technique. In this approach there is negligible contamination from b→dγ decays, which are expected to have a much larger CP asymmetry. We find ACP=0.002±0.050(stat)±0.030(syst) for B→Xsγ events having recoil mass smaller than 2.1 GeV/c2. The analysis is based on a data sample of 140 fb−1 recorded at the Υ(4S) resonance with the Belle detector at the KEKB e+e− storage ring.Received 4 April 2004DOI:https://doi.org/10.1103/PhysRevLett.93.031803©2004 American Physical Society

We report improved measurements of branching fractions for $\stackrel{\ensuremath{\rightarrow}}{B}K\ensuremath{\pi},$ ${\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}},$ ${\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{0},$ and $K\overline{K}$ decays based on a data sample of 85.0 million $B\overline{B}$ pairs collected at the $\ensuremath{\Upsilon}(4S)$ resonance with the Belle detector at the KEKB ${e}^{+}{e}^{\ensuremath{-}}$ storage ring. This data sample is almost three times larger than the sample previously used. We observe clear signals for $\stackrel{\ensuremath{\rightarrow}}{B}K\ensuremath{\pi},$ ${\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}},$ and ${\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{0}$ decays and set upper limits on $\stackrel{\ensuremath{\rightarrow}}{B}K\overline{K}$ decays. The results can be used to give model-dependent constraints on the CKM angle ${\ensuremath{\varphi}}_{3},$ as well as limits on the hadronic uncertainty in the time-dependent analysis of the angle ${\ensuremath{\varphi}}_{2}.$

We report the first observation of the decay B+→ψ(3770)K+ where the ψ(3770) is reconstructed in the D0¯¯¯D0 and D+D− decay channels. The obtained branching fraction is B(B+→ψ(3770)K+)=(0.48±0.11±0.07)×10−3. We have measured the branching fraction for the decay B+→D0¯¯¯D0K+ to be (1.17±0.21±0.15)×10−3 and set a 90% confidence level upper limit of 0.90×10−3 for the decay B+→D+D−K+. We also present the results of a search for possible decays to D¯¯¯D and D0¯¯¯D0π0 of the recently observed X(3872) particle. The analysis is based on 88 fb−1 of data collected at the Υ(4S) resonance by the Belle detector at the KEKB asymmetric-energy e+e− collider.Received 23 January 2004DOI:https://doi.org/10.1103/PhysRevLett.93.051803©2004 American Physical Society

We report the observation of the decay B0-->pi(0)pi(0), using a 253 fb(-1) data sample collected at the Upsilon(4S) resonance with the Belle detector at the KEKB e(+)e(-) collider. The measured branching fraction is B(B0-->pi(0)pi(0))=(2.3(+0.4+0.2)(-0.5-0.3))x10(-6), with a significance of 5.8 standard deviations including systematic uncertainties. We also make a measurement of the direct CP violating asymmetry in this mode.

We report measurements of partial branching fractions of inclusive charmless semileptonic B-meson decays at the endpoint of the electron momentum spectrum. The measurements are made in six overlapping momentum intervals that have lower bounds ranging from 1.9 to 2.4 GeV/c and a common upper bound of 2.6 GeV/c, as measured in the centre of mass frame. The results are based on a sample of 29 million BB¯ pairs, accumulated by the Belle detector at the KEKB asymmetric e+e− collider operating on the ϒ(4S) resonance. In the momentum interval ranging from 1.9 to 2.6 GeV/c we measure the partial branching fraction ΔB(B→Xueνe)=(8.47±0.37±1.53)×10−4, where the first error is statistical and the second is systematic. A prediction of the partial rate R=(21.69±3.62−1.98+2.18)|Vub|2ps−1 in this momentum interval based on theory is calculated with input HQET parameters that have been derived from Belle's measurement of the B→Xsγ photon energy spectrum, where the first error is due to the uncertainty on HQET parameters and the second error is from theory. Using both ΔB(B→Xueνe) and R we find |Vub|=(5.08±0.47±0.42−0.23+0.26)×10−3, where the first error is from the partial branching fraction, and the second and third errors are from uncertainties in R.

We report results of a search for the invisible decay of the Υ(1S) via the Υ(3S)→π+π−Υ(1S) transition using a data sample of 2.9 fb−1 at the Υ(3S) resonance. The data were collected with the Belle detector at the KEKB asymmetric-energy e+e− collider. No signal is found, and an upper limit for the branching fraction at the 90% confidence level is determined to be B(Υ(1S)→invisible)<2.5×10−3.Received 23 November 2006DOI:https://doi.org/10.1103/PhysRevLett.98.132001©2007 American Physical Society

We report the first observation of exclusive decays of the type B-->D(*)N_NX, where N is a nucleon. Using a sample of 9.7x10(6)B_B pairs collected with the CLEO detector operating at the Cornell Electron Storage Ring, we measure the branching fractions B(B0-->D(*-)p_p pi(+)) = (6.5(+1.3)(-1.2)+/-1.0)x10(-4) and B(B0-->D(*-)p_n) = (14.5(+3.4)(-3.0)+/-2.7)x10(-4). Antineutrons are identified by their annihilation in the CsI electromagnetic calorimeter.

We report branching fractions and charge asymmetries for exclusive decays of charged and neutral B mesons to two-body final states containing a charmonium meson, $J/\ensuremath{\psi}$ or $\ensuremath{\psi}(2S).$ This result is based on a $29.4{\mathrm{fb}}^{\ensuremath{-}1}$ data sample collected at the $\ensuremath{\Upsilon}(4S)$ resonance with the Belle detector at the KEKB asymmetric ${e}^{+}{e}^{\ensuremath{-}}$ collider.

K^+K^- production in two-photon collisions has been studied using a large data sample of 67 fb^{-1} accumulated with the Belle detector at the KEKB asymmetric e^+e^- collider. We have measured the cross section for the process gamma gamma -&gt; K^+ K^- for center-of-mass energies between 1.4 and 2.4 GeV, and found three new resonant structures in the energy region between 1.6 and 2.4 GeV. The angular differential cross sections have also been measured.

A high precision study of the process γγ→pp¯ has been performed using a data sample of 89 fb−1 collected with the Belle detector at the KEKB e+e− collider. The cross section of pp¯ production has been measured at two-photon center-of-mass (c.m.) energies between 2.025 and 4.0 GeV and in the c.m. angular range of |cosθ∗|<0.6. Production of γγ→ηc→pp¯ is observed and the product of the two-photon width of the ηc and its branching ratio to pp¯ is determined.

We present a measurement of the angle ${\ensuremath{\phi}}_{1}$ of the Cabibbo-Kobayashi-Maskawa unitarity triangle using a time-dependent Dalitz analysis of $D\ensuremath{\rightarrow}{K}_{S}^{0}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ decays produced in neutral $B$ meson decay to a neutral $D$ meson and a light meson (${\overline{B}}^{0}\ensuremath{\rightarrow}{D}^{(*)}{h}^{0}$). The method allows a direct extraction of $2{\ensuremath{\phi}}_{1}$ and, therefore, helps to resolve the ambiguity between $2{\ensuremath{\phi}}_{1}$ and $\ensuremath{\pi}\ensuremath{-}2{\ensuremath{\phi}}_{1}$ in the measurement of $\mathrm{sin}2{\ensuremath{\phi}}_{1}$. We obtain $\mathrm{sin}2{\ensuremath{\phi}}_{1}=0.78\ifmmode\pm\else\textpm\fi{}0.44\ifmmode\pm\else\textpm\fi{}0.22$ and $\mathrm{cos}2{\ensuremath{\phi}}_{1}={1.87}_{\ensuremath{-}0.53\ensuremath{-}0.32}^{+0.40+0.22}$. The sign of $\mathrm{cos}2{\ensuremath{\phi}}_{1}$ is determined to be positive at 98.3% C.L.

We present a search for the decays B+→μ+νμ and B+→e+νe in a 253 fb−1 data sample collected at the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric-energy B factory. We find no significant evidence for a signal and set 90% confidence level upper limits of B(B+→μ+νμ)<1.7×10−6 and B(B+→e+νe)<9.8×10−7.

The India-based Neutrino Observatory (INO) collaboration is planning to set-up a magnetized Iron-CALorimeter (ICAL) to study atmospheric neutrino oscillations with precise measurements of oscillations parameters. The ICAL uses 50 kton iron as target mass and about 28800 Resistive Plate Chambers (RPC) of 2 m × 2 m in area as active detector elements. As part of its R&D program, a prototype detector stack comprising 12 layers of RPCs of 1 m × 1 m in area has been set-up at Tata Institute of Fundamental Research (TIFR) to study the detector parameters using cosmic ray muons. We present here a study of muon flux measurement at sea level and lower latitude. (Site latitude: 18°54'N, longitude: 72°48'E.)

We present measurements of the reduction of light output by plastic scintillators irradiated in the CMS detector during the 8 TeV run of the Large Hadron Collider and show that they indicate a strong dose rate effect. The damage for a given dose is larger for lower dose rate exposures. The results agree with previous measurements of dose rate effects, but are stronger due to the very low dose rates probed. We show that the scaling with dose rate is consistent with that expected from diffusion effects.

The India-Based Neutrino Observatory (INO) collaboration houses the miniICAL detector, at the transit campus of IICHEP, Madurai, India, which serves as a prototype-detector of the larger Iron-Calorimeter detector (ICAL). The purpose of miniICAL lies in unraveling the intricate engineering challenges inherent in constructing a substantial ICAL-type detector. To explore the feasibility of building a large-scale neutrino experiment at shallow depths the collaboration has embarked upon the construction of a Cosmic Muon Veto Detector (CMVD) around the miniICAL detector. The primary objective of this endeavor revolves around attaining a veto efficiency surpassing $99.99\%$, while simultaneously maintaining a false-positive rate lower than $10^{-5}$. The CMVD system is based on extruded plastic scintillators (EPS) and utilizes wavelength-shifting fibers to collect scintillation photons and uses silicon photomultipliers (SiPMs) as photo-transducers. The expected performance of the CMVD is estimated using simulated muon tracks in the miniICAL stack taking into account efficiency, multiplicity of RPC detectors from the miniICAL data as well as the noise of SiPM, observed SiPM spectra and time resolution due to cosmic muon along the whole length of EPS etc. The CMVD experiment is a crucial step in the larger context of neutrino research, by increasing the veto efficiency of cosmic muons, the CMVD experiment helps to pave the way for future large-scale shallow-depth neutrino experiments, providing valuable insights into the study of neutrinos and their properties.

The B→D(∗)K−K(∗)0 decays have been observed for the first time. The branching fractions of the B→D(∗)K−K(∗)0 decay modes are measured. Significant signals are found for the B→D(∗)K−K∗0 and B−→D0K−K0S decay modes. The invariant mass and polarization distributions for the K−K∗0 and K−K0S subsystems have been studied. For the K−K∗0 sybsystem these distributions agree well with those expected for two-body B→D(∗)a1−(1260) decays, with a1−(1260)→K−K∗0. The analysis was done using 29.4 fb−1 of data collected with the Belle detector at the e+e− asymmetric collider KEKB.

We report the observation of B0 decays to the K+π−π0 final state using a data sample of 78 fb−1 collected by the Belle detector at the KEKB e+e− collider. With no assumptions about intermediate states in the decay, the branching fraction is measured to be (36.6−4.3+4.2±3.0)×10−6. We also search for B decays to intermediate two-body states with the same K+π−π0 final state. Significant B signals are observed in the ρ(770)−K+ and K*(892)+π− channels, with branching fractions of (15.1−3.3−1.5−2.1+3.4+1.4+2.0)×10−6 and (14.8−4.4−1.0−0.9+4.6+1.5+2.4)×10−6, respectively. The first error is statistical, the second is systematic and the third is due to the largest possible interference. Contributions from other possible two-body states will be discussed. No CP asymmetry is found in the inclusive K+π−π0 or ρ−K+ modes, and we set 90% confidence level bounds on the asymmetry of −0.12<ACP<0.26 and −0.18<ACP<0.64, respectively.

Using 29.1fb−1 of data accumulated at the Υ(4S) with the Belle detector at KEKB, we have studied the decay modes B0→Λ+c¯pπ+π−, B−→Λ+c¯pπ−, and B0→Λ+c¯p. We report branching fractions of exclusive B decays to charmed baryons with four-, three- and two-body final states, including intermediate Σ++c and Σ0c states. We observed B0→Σc(2455)++¯pπ− for the first time with a branching fraction of (2.38+0.63−0.55±0.41±0.62)×10−4 and observed evidence for the two-body decay B−→Σc(2455)0¯p with a branching fraction of (0.45+0.26−0.19±0.07±0.12)×10−4. We also set improved upper limits for the two-body decays B0→Λ+c¯p and B−→Σc(2520)0¯p. Received 25 August 2002DOI:https://doi.org/10.1103/PhysRevD.66.091102©2002 American Physical Society

We present a measurement of the Cabibbo-Kobayashi-Maskawa matrix element /Vub/, based on 253 fb(-1) of data collected by the Belle detector at the KEKB e+ e- asymmetric collider. Events are tagged by fully reconstructing one of the B mesons, produced in pairs from Gamma(4S). The signal for b --> u semileptonic decay is distinguished from the b --> c background using the hadronic mass Mx, the leptonic invariant mass squared q2 and the variable P+ [triple bond] Ex - /px/. The results are obtained for events with p(l)* > or = 1 GeV/c, in three kinematic regions (1) Mx < 1.7 GeV/c2, (2) Mx < 1.7 GeV/c2 combined with q2 > 8 GeV2/c2, and by (3) P+ < 0.66 GeV/c. The matrix element /Vub/ is found to be (4.09 +/- 0.19 +/- 0.20(+0.14) -0.15 +/- 0.18) x 10(-3), where the errors are statistical, systematic including Monte Carlo modeling, theoretical, and from shape function parameter determination, respectively.

Using kaon secondary interactions in the material of the Belle detector, we search for both inclusive and exclusive production of the Θ(1540)+. We set an upper limit of 2.5% at the 90% C.L. on the ratio of the Θ(1540)+ to Λ(1520) inclusive production cross sections. We also search for the Θ(1540)+ as an intermediate resonance in the charge exchange reaction K+n→pKS0. We set an upper limit of ΓΘ+<0.64MeV at the 90% C.L. for mΘ+=1.539MeV/c2. These results are obtained from a 397fb−1 data sample collected with the Belle detector near the ϒ(4S) resonance, at the KEKB asymmetric energy e+e− collider.

KS0KS0 production in two-photon collisions has been studied using a 397.6 fb−1 data sample collected with the Belle detector at the KEKB e+e− collider. For the first time the cross sections are measured in the two-photon center-of-mass energy range between 2.4 GeV and 4.0 GeV and angular range |cosθ∗|<0.6. Combining the results with measurements of γγ→K+K− from Belle, we observe that the cross section ratio σ(KS0KS0)/σ(K+K−) decreases from ∼0.13 to ∼0.01 with increasing energy. Signals for the χc0 and χc2 charmonium states are also observed.

Sub-relativistic magnetic monopoles are predicted from the GUT era by theory. To date there have been no confirmed observations of such exotic particles. The Iron CALorimeter (ICAL) at the India-based Neutrino Observatory (INO) aims to measure the neutrino oscillation parameters precisely. As it is a tracking detector there is also the possibility of detecting magnetic monopoles in the sub-relativistic region. Using ICAL the magnetic monopole event is characterised by the large time intervals of up to 0.3 μs between the signals in successive layers of the active detectors. The aim of this study is to identify the sensitivity of ICAL for a particle carrying magnetic charge in the mass range from 107–1017GeV with β=v/c ranging from 10-3-7×10-1. In this velocity and mass range, the detector sensitivity is ∼1.6×10-16(cm2srs)-1 for a live-time of 10y. The sensitivity can be increased by a factor of two with some additional detectors on the walls of the cavern.

We present an observation and time-integrated rate measurement of the decay ${D}^{0}\ensuremath{\rightarrow}{K}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}$ produced in $9{\mathrm{fb}}^{\ensuremath{-}1}$ of ${e}^{+}{e}^{\ensuremath{-}}$ collisions near the $\ensuremath{\Upsilon}(4S)$ resonance. The signal is inconsistent with an upward fluctuation of the background by 4.9 standard deviations. We measured the time-integrated rate of ${D}^{0}\ensuremath{\rightarrow}{K}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}$ normalized to the rate of $\overline{{D}^{0}}\ensuremath{\rightarrow}{K}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}$ to be ${0.0043}_{\ensuremath{-}0.0010}^{+0.0011}(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.0007(\mathrm{syst})$. This decay can be produced by doubly Cabibbo-suppressed decays or by the ${D}^{0}$ evolving into a $\overline{{D}^{0}}$ through mixing, followed by a Cabibbo-favored decay to ${K}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}$. We also found the $\mathrm{CP}$ asymmetry $A\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}({9}_{\ensuremath{-}22}^{+25})%$ be consistent with zero.

The decays $\bar{B^0} \to D_{sJ}^+ K^-$ and $\bar{B^0} \to D_{sJ}^- \pi^+$ are studied for the first time. A significant signal is observed in the $\bar{B^0} \to D_{sJ}^*(2317)^+ K^-$ decay channel with ${\cal B}(\bar{B^0} \to D_{sJ}^*(2317)^+ K^-) \times {\cal B} (D_{sJ}^*(2317)^+ \to D_s^+ \pi^0) = (5.3^{+1.5}_{-1.3} \pm 0.7 \pm 1.4) \times 10^{-5}$. No signals are observed in the $\bar{B^0} \to D_{sJ}^*(2317)^- \pi^+$, $\bar{B^0} \to D_{sJ}(2460)^+ K^-$ and $\bar{B^0} \to D_{sJ}(2460)^- \pi^+$ decay modes, and upper limits are obtained. The analysis is based on a dataset of 140 fb$^{-1}$ collected by the Belle experiment at the asymmetric $e^+ e^-$ collider KEKB.

We present a precise measurement of the standard model CP-violation parameter sin(2phi1), the direct CP violation parameter |lambda|, the lifetimes of charged and neutral B mesons and their ratio, and the B0-B0bar mixing parameter Delta m_d based on a sample of 152 x 10^6 BB-bar pairs collected at the Y(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. One of two B mesons is fully reconstructed in a CP-eigenstate or a flavor-eigenstate decay channel. The flavor of the accompanying B meson is identified from its decay products. From the asymmetry in the distribution of the time interval between the two B meson decay points, we obtain sin(2phi1) = 0.728 +/- 0.056(stat) +/- 0.023(syst), |lambda| = 1.007 +/- 0.041(stat) +/- 0.033(syst), tau_B0 = 1.534 +/- 0.008(stat) +/- 0.010(syst) ps, tau_B+ = 1.635 +/- 0.011(stat) +/- 0.011(syst) ps, tau_B+/tau_B0 = 1.066 +/- 0.008(stat) +/- 0.008(syst) and Delta m_d = 0.511 +/- 0.005(stat) +/- 0.006(syst) ps-1. The results for sin(2phi1) and |lambda| are the most precise measurements performed so far, and are consistent with the standard model expectations. The significance of the observed deviation from unity in the lifetime ratio exceeds five standard deviations.

We report on the first observation of D0/1(2420)-->D0pi- pi+ and D+/1(2420-->D+ pi- pi+ decays (where the contribution from the dominant known D1-->D*pi decay mode is excluded) in the B- -->D0/1pi-) and (-)B0-->D+/1pi- decays, respectively. The observation is based on 15.2 x 10(7) B(-)B events collected with the Belle detector at the KEKB collider. We also set 90% confidence level upper limits for the branching fractions of the four following decays: B- -->D0/1pi-, D01-->D(*0)pi- pi+, (-)B0-->D+/1pi-, D+/1-->D(*+) pi- pi+, B- -->D(*0)2(2460)pi-, D(*0)2 -->D(*0) pi- pi+, (-)B0-->D(*+)2(2460)pi-, D(*+)2-->D(*+)pi- pi+.

We report evidence for the exclusive two-body charmless hadronic B meson decay B-->eta'pi, and improved measurements of B-->eta'K. The results are obtained from a data sample of 386x10(6) BB pairs collected at the Upsilon(4S) resonance, with the Belle detector at the KEKB asymmetric-energy e+e- collider. We measure B(B+-->eta'pi+)=[1.76(-0.62)(+0.67)(stat)(-0.14)(+0.15)(syst)]x10(-6) and B(B0-->eta'pi0)=[2.79(-0.96)(+1.02)(stat)(-0.34)(+0.25)(syst)]x10(-6). We also find the ratio of B(B+-->eta'K+)/B(B0-->eta'K0)=1.17+/-0.08(stat)+/-0.03(syst) and measure the direct CP asymmetries for the charged modes.

We report the results of a study of two-body B meson decays to the complete set of $K\ensuremath{\pi},$ $\ensuremath{\pi}\ensuremath{\pi},$ and $K\overline{K}$ final states. The study is performed on a data sample of $31.7\ifmmode\pm\else\textpm\fi{}0.3$ million $B\overline{B}$ events recorded on the $\ensuremath{\Upsilon}(4\mathrm{S})$ resonance by the Belle experiment at KEKB. We observe significant signals in all $K\ensuremath{\pi}$ final states and in the ${\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ and ${\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{0}$ final states. We set limits on the ${\ensuremath{\pi}}^{0}{\ensuremath{\pi}}^{0}$ and $K\overline{K}$ final states. A search is performed for partial-rate asymmetries between conjugate states for flavor-specific final states.

We have searched for the two-body decay of the B meson to a light pseudoscalar meson h = pi(+/-),K+/-,K(0)(S) and a massless neutral feebly interacting particle X(0) such as the familon, the Nambu-Goldstone boson associated with a spontaneously broken global family symmetry. We find no significant signal by analyzing a data sample containing 9.7x10(6) BBbar mesons collected with the CLEO detector at the Cornell Electron Storage Ring, and set 90% C.L. upper limits italicB(B(+/-) --> h(+/-)X(0)) = 4.9x10(-5) and italicB(B(0) --> K(0)(S)X(0)) = 5.3x10(-5). These limits correspond to a lower bound of approximately 10(8) GeV on the family symmetry breaking scale with vector coupling involving the third generation of quarks.

We report on a study of B0→D(∗)0π+π− decays using 29.1 fb−1 of e+e− annihilation data recorded at the ϒ(4S) resonance with the Belle detector at the KEKB storage ring. Making no assumptions about the intermediate mechanism, the branching fractions for B0→D0π+π− and B0→D∗0π+π− are determined to be (8.0±0.6±1.5)×10−4 and (6.2±1.2±1.8)×10−4, respectively. An analysis of B0→D0π+π− candidates yields to the first observation of the color-suppressed hadronic decay B0→D0ρ0 with the branching fraction (2.9±1.0±0.4)×10−4. We measure the ratio of branching fractions B(B0→D0ρ0)/B(B0→D0ω)=1.6±0.8.

Using 12.7 fb(-1) of data collected with the CLEO detector at CESR, we observed two-photon production of the cc states chi(c0) and chi(c2) in their decay to pi(+)pi(-)pi(+)pi(-). We measured gamma(gammagamma)(chi(c))xB(chi(c)-->pi(+)pi(-)pi(+)pi(-)) to be 75+/-13(stat)+/-8(syst) eV for the chi(c0) and 6.4+/-1.8(stat)+/-0.8(syst) eV for the chi(c2), implying gamma(gammagamma)(chi(c0)) = 3.76+/-0.65(stat)+/-0.41(syst)+/-1.69(br) keV and gamma(gammagamma)(chi(c2)) = 0.53+/-0.15(stat)+/-0.06(syst)+/-0.22(br) keV. Also, cancellation of dominant experimental and theoretical uncertainties permits a precise comparison of gamma(gammagamma)(chi(c0))/gamma(gammagamma)(chi(c2)), evaluated to be 7.4+/-2.4(stat)+/-0.5(syst)+/-0.9(br), with QCD-based predictions.

We report on a search for B(0)-->D(*0)K(*0) decays based on 85 x 10(6) BB events collected with the Belle detector at KEKB. The B(0)-->D0K(0) and B(0)-->D0K(*0) decays have been observed for the first time with the branching fractions B(B(0)-->D0K(0))=(5.0(+1.3)(-1.2)+/-0.6)x10(-5) and B(B(0)-->D0K(*0))=(4.8(+1.1)(-1.0)+/-0.5)x10(-5). No significant signal has been found for the B(0)-->D(*0)K*0) and B(0)-->D(*0)K(*0) decay modes, and upper limits at 90% C.L. are presented.

We report measurements of radiative B decays with Kηγ final states, using a data sample of 253fb−1 recorded at the ϒ(4S) resonance with the Belle detector at the KEKB e+e− storage ring. We observe B+→K+ηγ for the first time with a branching fraction of (8.4±1.5(stat)−0.9+1.2(syst))×10−6 for MKη<2.4 GeV/c2, and find evidence of B0→K0ηγ. We also search for B→K3∗(1780)γ.

We report measurements of time-dependent decay rates for ${B}^{0}\ensuremath{\rightarrow}{D}^{(*)\ensuremath{-}}{\ensuremath{\pi}}^{+}$ decays and extraction of $CP$ violation parameters that depend on ${\ensuremath{\phi}}_{3}$. Using fully reconstructed ${D}^{(*)}\ensuremath{\pi}$ events and partially reconstructed ${D}^{*}\ensuremath{\pi}$ events from a data sample that contains $386\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $B\overline{B}$ pairs that was collected near the $\ensuremath{\Upsilon}(4S)$ resonance, with the Belle detector at the KEKB asymmetric energy ${e}^{+}{e}^{\ensuremath{-}}$ collider, we obtain the $CP$ violation parameters ${S}^{+}({D}^{(*)}\ensuremath{\pi})$ and ${S}^{\ensuremath{-}}({D}^{(*)}\ensuremath{\pi})$. We obtain ${S}^{+}({D}^{*}\ensuremath{\pi})=0.049\ifmmode\pm\else\textpm\fi{}0.020(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.011(\mathrm{sys})$, ${S}^{\ensuremath{-}}({D}^{*}\ensuremath{\pi})=0.031\ifmmode\pm\else\textpm\fi{}0.019(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.011(\mathrm{sys})$, and ${S}^{+}(D\ensuremath{\pi})=0.031\ifmmode\pm\else\textpm\fi{}0.030(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.012(\mathrm{sys})$, ${S}^{\ensuremath{-}}(D\ensuremath{\pi})=0.068\ifmmode\pm\else\textpm\fi{}0.029(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.012(\mathrm{sys})$. These results are an indication of $CP$ violation in ${B}^{0}\ensuremath{\rightarrow}{D}^{*\ensuremath{-}}{\ensuremath{\pi}}^{+}$ and ${B}^{0}\ensuremath{\rightarrow}{D}^{\ensuremath{-}}{\ensuremath{\pi}}^{+}$ decays at the $2.5\ensuremath{\sigma}$ and $2.2\ensuremath{\sigma}$ levels, respectively. If we use the values of ${R}_{{D}^{(*)}\ensuremath{\pi}}$ that are derived using assumptions of factorization and SU(3) symmetry, branching fraction measurements for the $B\ensuremath{\rightarrow}{D}_{s}^{(*)}\ensuremath{\pi}$ modes, and lattice QCD calculations, we can restrict the allowed region of $|\mathrm{sin}(2{\ensuremath{\phi}}_{1}+{\ensuremath{\phi}}_{3})|$ to be above 0.44 and 0.52 at 68% confidence level from the ${D}^{*}\ensuremath{\pi}$ and $D\ensuremath{\pi}$ modes, respectively.

We present a new measurement of the time-dependent CP-violating parameters in B0→π+π− decays with 275×106 BB¯ pairs collected with the Belle detector at the KEKB asymmetric-energy e+e− collider operating at the Υ(4S) resonance. We find 666±43 B0→π+π− events and measure the CP-violating parameters: Sππ=−0.67±0.16(stat)±0.06(syst) and Aππ=+0.56±0.12(stat)±0.06(syst). We find evidence for large direct CP violation with a significance greater than 4 standard deviations for any Sππ value. Using isospin relations, we obtain 95.4% confidence intervals for the Cabibbo-Kobayashi-Maskawa quark-mixing matrix angle ϕ2 of 0°<ϕ2<19° and 71°<ϕ2<180°.Received 29 April 2005DOI:https://doi.org/10.1103/PhysRevLett.95.101801©2005 American Physical Society

We report a measurement of the branching fraction for the decay B+ --> rho(+) pi(0) based on a 140 fb(-1) data sample collected with the Belle detector at the KEKB asymmetric e(+)e(-) collider. We measure the branching fraction B(B(+) --> rho(+)pi(0)) = (13.2 +/- 2.3(stat)(+1.4)(-1.9)(syst)) x 10(-6), and the CP-violating asymmetry A(CP)(B-/+ -->rho(-/+)pi(0))=0.06 +/- 0.17(stat)(+0.04)(-0.05)(syst).

We present the first observation of τ lepton decays to hadronic final states with a ϕ-meson. This analysis is based on 401 fb−1 of data accumulated at the Belle experiment. The branching fraction obtained is B(τ−→ϕK−ντ)=(4.05±0.25±0.26)×10−5.