Using data taken with the CLEO-c detector at the Cornell Electron Storage Ring, we have investigated the direct photon momentum spectrum in the decay J/psi->gamma+gluon+gluon, via the 'tagged' process: e+e- -> psi(2S); psi(2S)->J/psi pi+pi-; J/psi->photon + X. Including contributions from two-body radiative decay processes, we find the ratio of the inclusive direct photon branching fraction to that of the dominant three-gluon branching fraction to be R=0.137+/-0.001+/-0.016+/-0.004, where the errors shown are statistical, systematic, and the model-dependent uncertainty related to the extrapolation to zero photon energy. The shape of the scaled photon energy spectrum in J/psi->gg gamma is observed to be very similar to that of Upsilon(1S)->gg gamma. The R value obtained is roughly consistent with that expected by a simple quark-charge scaling of the value determined at the Upsilon(1S), but somewhat higher than the value expected from the running of the strong coupling constant.
Using 605/fb of data collected at the Upsilon(4S) resonance we present a measurement of the inclusive radiative B-meson decay channel, B to X_s gamma. For the lower photon energy thresholds of 1.7, 1.8, 1.9 and 2.0GeV, as defined in the rest frame of the B-meson, we measure the partial branching fraction and the mean and variance of the photon energy spectrum. At the 1.7GeV threshold we obtain the partial branching fraction BF(B to X_s gamma) = (3.45 +/- 0.15 +/- 0.40) x 10^-4, where the errors are statistical and systematic.
We have searched for the bottomonium eta_b(1S) via the hindered magnetic dipole (M1) photon transition Upsilon(3S) -> gamma eta_b(1S). No evidence for such a transition is found in the data sample of 4.7 x 10^6 Upsilon(3S)'s collected with the CLEO-III detector. We set upper limits on the branching ratio from 9.30 to 9.43 GeV/c^2 of eta_b(1S) masses. These upper limits rule out many previously published phenomenological estimates of the rate for this transition.
Using e+e- collision data taken with the CLEO-c detector at the Cornell Electron Storage Ring, we have investigated the direct photon spectrum in the decay psi(2S)->gamma+gluon+gluon. We determine the ratio R of that inclusive direct photon decay rate to that of the three-gluon decay rate psi(2S)->3-gluon to be R(z>0.4)=0.070+/-0.002+/-0.019+/-0.011, with z defined as the scaled photon energy relative to the beam energy. The errors shown are statistical, systematic, and that due to the uncertainty in the input branching fractions used to extract the ratio, respectively. This R value is approxi…
We report a fully inclusive measurement of the flavor changing neutral current decay $B\to X_sγ$ in the energy range $1.7 \GeV\le E^\mathrm{c.m.s}_γ\le 2.8 \GeV$, covering 97% of the total spectrum, where c.m.s is the center of mass system. Using $605\ifb$ of data, we obtain in the rest frame of the $B$-meson ${\mathcal B}(B\to X_sγ: E^B_γ>1.7 \mathrm{GeV})= (3.31 \pm 0.19 \pm 0.37 \pm 0.01)\times 10^{-4}$, where the errors are statistical, systematic and from the boost correction needed to transform from the rest frame of the $Υ(4S)$ (c.m.s) to that of the $B$-meson, respectively. We also mea…
The $b \rightarrow s γ$, $b \rightarrow d γ$ and $b \rightarrow s \ell^+ \ell^-$ processes are allowed at higher order via the electroweak loop or box diagrams in the Standard model. It is sensitive probe to search for new physics beyond the Standard model because new particles might enter in the loop. We present preliminary results of branching fraction of the $\bar{B} \rightarrow X_s γ$, $CP$ asymmetry in the $\bar{B} \rightarrow X_{s+d} γ$, and the forward-backward asymmetry in the $\bar{B} \rightarrow X_s \ell^+ \ell^-$. The results are based on a data sample containing $772 \times 10^6 B\…
We discuss in detail the photon spectrum of radiative Upsilon 1S decays taking into account a number of results that have recently appeared in the literature. In particular, we show how to consistently combine expressions which are valid in the upper end-point region, where NRQCD factorization breaks down, with those of the central region, where NRQCD factorization holds. An excellent description of data is achieved, but theoretical errors are large.
The present status of the measurement of the inclusive semileptonic $B$ decays is reviewed. In particular the determination of the Cabibbo-Kobayashi-Maskawa matrix elements $|V_{cb}|$ and $|V_{ub}|$ is discussed and some future prospects are given.
We present an update on total and partial branching fractions and on CP asymmetries in the semi-inclusive decay B -> Xs l+l-. Further, we summarize our results on branching fractions and CP asymmetries for semi-inclusive and fully-inclusive B -> Xs gamma decays. We present the first result on the CP asymmetry difference of charged and neutral B -> Xs gamma$ decays yielding the first constraint on the ratio of Wilson coefficients Im (C8/C7).
The present status of the measurement of the semileptonic B decays is reviewed. Emphasis is given on the factors affecting experimental errors of the Cabibbo-Kobayashi-Masawa matrix element |Vcb | and |Vub |.
We study the inclusive decays of Ds+ mesons, using data collected near the Ds*+ Ds- peak production energy E_cm=4170 MeV by the CLEO-c detector. We report the inclusive yields of Ds+ decays to K^+ X, K^- X, KS0 X, pi^+ X, pi^- X, pi^0 X, eta X, eta' X, phi X, omega X and f0(980) X, and also decays into pairs of kaons, Ds+ -> KK-bar X. Using these measurements, we obtain an overview of Ds+ decays.
In a search for new phenomena in a signature suppressed in the standard model of elementary particles (SM), we compare the inclusive production of events containing a lepton, a photon, significant transverse momentum imbalance (MET), and a jet identified as containing a b-quark, to SM predictions. The search uses data produced in proton-antiproton collisions at 1.96 TeV corresponding to 1.9 fb-1 of integrated luminosity taken with the CDF detector at the Fermilab Tevatron. We find 28 lepton+photon+MET+b events versus an expectation of 31.0+4.1/-3.5 events. If we further require events to conta…
The inclusive production rate of phi mesons from the decay of b hadrons produced in Z0 decays was measured to be Br(b->phi+X) = 0.0282+-0.0013(stat.)+-0.0019(syst.), using data collected by the OPAL detector at LEP.
We present preliminary results on two analyses performed by the SLD Collaboration using inclusive B decays: a search for CP violation and a search for the b --> sg transition.
A generator for inclusive b -> u l nu decays has been developed. Different prescriptions have been applied to describe the kinematics of the b-quark inside the hadron and the generation of the hadronic final states. Results are presented with particular attention to the invariant mass of the hadronic system recoiling against the lepton and its resonance decomposition. These studies are of special relevance for the extraction of Vub from semileptonic B decays at LEP and at B factories.
A study of b quark hadronisation is presented using inclusively reconstructed B hadrons in about four million hadronic Z decays recorded in 1992-2000 with the OPAL detector at LEP. The data are compared to different theoretical models, and fragmentation function parameters of these models are fitted. The average scaled energy of weakly decaying B hadrons is determined to be <xe>=0.7193+-0.0016(stat)+0.0036-0.0031(syst)
Recent results on inclusive charmless semileptonic decays of B mesons are reviewed. Emphasis is given to measurements on the recoil of fully reconstructed B mesons, which allow to exploit several regions of phase space. Preliminary averages of the CKM matrix element $|V_{ub}|$ from the Heavy Flavour Working Group are shown, using four different theoretical calculations.
Electron-positron annihilation data collected by the BABAR detector near the Y(4S) resonance are used to study the inclusive decay of B mesons to D_S^(+/-) and D_S^(*+/-) mesons, where the D_S^(+/-) is reconstructed using the decay D_S^(+/-) --> phi pi^(+/-). The production fraction of inclusive D_S^((*)+/-) and the corresponding momentum spectra have been determined. The exclusive decays B^0 --> D^(*-)D_S^((*)+) are observed with a partial reconstruction technique which uses the soft pion from the D^(*+/-) decay in association with the reconstructed D_S^((*)+/-). The beam energy constraint is…
On the basis of the study of inclusive hadronic events, two methods are adopted to determine the number of produced psi(2S) events collected by BES in 2001-2002 run, which is 14 Million with the uncertainty of 4%.
Using the Belle detector operating at the KEKB e+e- storage ring, we have measured the mean multiplicity and the momentum spectrum of neutral pions from the decays of the Upsilon(4S) resonance. We measure a mean of 4.70 +/- 0.04 +/- 0.22 neutral pions per Upsilon(4S) decay.
The inclusive production of charmonium mesons in B meson decay has been studied in a 20.3 fb$^{-1}$ data set collected by the BaBar experiment operating at the $Υ(4S)$ resonance. Branching fractions have been measured for the inclusive production of the charmonium mesons $J/ψ$, $ψ(2S)$, $χ_{c1}$, and $χ_{c2}$. The branching fractions are also presented as a function of the center-of-mass momentum of the mesons and of the helicity of the $J/ψ$.
We present measurements of the inclusive semileptonic branching fractions of charged and neutral B mesons using 20.6 fb-1 of data measured at the Upsilon(4S) with the BABAR detector. Events are tagged with a fully reconstructed hadronic decay of a B meson. The correlation between the flavor of the tag B meson and the electron charge allows the separation of prompt semileptonic B decays and cascade semileptonic charm decays. We obtain the preliminary inclusive semileptonic branching fraction of charged B mesons b+ = 0.103+/-0.006+/-0.005, neutral B mesons b0 = 0.104+/-0.008+/-0.005, their avera…
We report on the measurement of inclusive charmless semileptonic B decays $B \to X_{u} \ell ν$. The analysis makes use of hadronic tagging and is performed on the full data set of the Belle experiment comprising 772 million $B\bar{B}$ pairs. In the proceedings, the preliminary results of measurements of partial branching fractions and the CKM matrix element $|V_{ub}|$ are presented.
Using 8.5M B-anti-B events recorded by the BABAR detector the yield of inclusive J/psi, the branching ratios of psi(2S) and chi_C1 are presented. Combining the charmonium state with either a K+,KS, K*+ or K*0 exclusive B decays are reconstructed and their branching ratios determined. Using the fully reconstructed decays, both the B0 and B+ masses and their difference is measured. Finally the contributions of CP even and odd amplitudes in the decay B to J/psi K* are determined from an angular analysis.
A largely model-independent measurement of the inclusive electron momentum spectrum and branching fraction for semileptonic decays of B mesons is presented based on data recorded at the Upsilon(4S) resonance with the BABAR detector. Backgrounds from secondary charm decays are separated from prompt B decays using charge and angular correlations between the electron from one B meson and a high momentum electron tag from the second B meson. The resulting branching fraction is BR(B -> X e nu) = (10.87 +-0.18(stat)+-0.30(syst))%. Based on this measurement we determine the CKM matrix element |V_cb|.
Using the data sample of about 33 pb-1 collected at and around 3.773 GeV with the BES-II detector at the BEPC collider, we have studied inclusive K0~/K0 and K*(892)+- decays of D0 and D+ mesons. The branching fractions for the inclusive K0~/K0 and K*(892)- decays are measured to be BF(D0 to K0~/K0 X)=(47.6+-4.8+-3.0)%, BF(D+ to K0~/K0 X)=(60.5+-5.5+-3.3)%, BF(D0 to K*- X)=(15.3+- 8.3+- 1.9)% and BF(D+ to K*- X)=(5.7+- 5.2+- 0.7)%. The upper limits of the branching fractions for the inclusive K*(892)+ decays are set to be BF(D0 to K*+ X)<3.6% and BF(D+ to K*+ X) <20.3% at 90% confidence level.
We report updates on two analyses of inclusive semileptonic B decays based on a dataset of 89 million BB events recorded with the BABAR detector at the Y(4S) resonance. Events are selected by fully reconstructing the decay of one B meson and identifying a charged lepton from the decay of the other B meson. In the first analysis, the measurement of the first and second moment of the hadronic mass distribution in Cabibbo-favored B ->X_c l nu decays allows for the determination of the nonperturbative parameters $\barΛ$ and $λ_1$ of Heavy Quark Effective Theory (HQET) and |Vcb|. In the second anal…
We report on measurements of the inclusive production rate of Sigma+ and Sigma0 baryons in hadronic Z decays collected with the L3 detector at LEP. The Sigma+ baryons are detected through the decay Sigma+ -> p pi0, while the Sigma0 baryons are detected via the decay mode Sigma0 -> Lambda gamma. The average numbers of Sigma+ and Sigma0 per hadronic Z decay are measured to be: < N_Sigma+ > + < N_Sigma+~ > = 0.114 +/- 0.011 (stat) +/- 0.009 (syst), < N_Sigma0 > + < N_Sigma0~ > = 0.095 +/- 0.015 (stat) +/- 0.013 (syst). These rates are found to be higher than the predictions from Monte Carlo hadro…
With singly-tagged $\bar D$ samples selected from the data collected at and around 3.773 GeV with the BESII detector at the BEPC collider, we have measured the branching fractions for the inclusive $K^\pm$ decays of $D^+$ and $D^0$ mesons, which are $BF(D^+\to K^-X) = (24.7 \pm 1.3 \pm 1.2)%$, $BF(D^+\to K^+X) = (6.1 \pm 0.9 \pm 0.4) %$, $BF(D^0\to K^-X) = (57.8 \pm 1.6 \pm 3.2) %$ and $BF(D^0\to K^+X) = (3.5 \pm 0.7 \pm 0.3) %$, respectively. We have also measured the branching fractions for the inclusive semileptonic decays of $D^+$ and $D^0$ mesons to be $BF(D^+ \to e^+ X)=(15.2 \pm 0.9 \pm…
The inclusive production of prompt photons with energy above 10 GeV is measured using the OPAL detector in hadronic Z^0 decays at LEP. In contrast to previous measurements, the prompt photons were not required to be isolated. The production rate and energy spectrum are found to be in agreement with QCD predictions for the quark-to-photon fragmentation function.
We report a measurement of the inclusive electron energy spectrum for semileptonic decays of B mesons in a data sample of 52 million Y4S -> BBar decays collected with the BABAR detector at the PEP-II asymmetric-energy B-meson factory at SLAC. We determine the branching fraction, first, second, and third moments of the spectrum for lower cut-offs on the electron energy between 0.6 and 1.5 GeV. We measure the partial branching fraction to be Br(B -> X e nu, E_e>0.6 GeV) = (10.36 +-0.06(stat.) +-0.23(sys))%.
Radiative and electroweak penguin mediated decays of $B$ mesons are a great probe for physics beyond the Standard Model of particle physics. Furthermore, recently anomalies on exclusive $b \rightarrow s \ell^{+} \ell^{-}$ processes, which may imply lepton flavor universality violation, have been observed. Belle II experiment sheds light on the anomalies with the measurement of an inclusive analysis in this mode. Thanks to smaller hadronic uncertainties compared with exclusive modes, complementary information can be provided. Belle II is also a unique experiment to search for processes involvin…
We have measured the branching fraction of the inclusive radiative B meson decay B --> X(s) gamma to be Br(B->X(s)gamma)=(3.36 +/- 0.53(stat) +/- 0.42(sys) +0.50-0.54(th)) x 10^{-4}. The result is based on a sample of 6.07 x 10^6 BBbar events collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric e^+e^- storage ring.
Radiative and electroweak decays of B mesong (B to X_{s(d)}γ and B to X_{s(d)}\ell\ell, respectively, where X is a hadronic system and s or d labels the underlying quark process b to s(d)γ) provide good places to search for new physics (NP) beyond the standard model. Recent BaBar measurements are reported: inclusive BF(B to X_s γ), direct CP asymmetry for inclusive X_s γ and X_{s+d} γ, and searches for the rare decays B to π(η)\ell\ell. No evidence for NP was found, but several constraints are discussed.
A measurement of the first four moments of the hadronic mass distribution in B->Xc lv decays is presented for minimum lepton momenta varying between 0.9 and 1.6 GeV, using data recorded with the BaBar detector. Furthermore, a measurement of the inclusive electron energy spectrum for semileptonic B decays together with a measurement of its first, second and third moments for minimum electron energies between 0.6 and 1.5 GeV is reported. We determine the inclusive B->Xc lv branching fraction, B_clv, the CKM matrix element |V_cb|, and other heavy-quark parameters from a simultaneous fit to the me…
We review the present status of rare B decays, focusing on inclusive decay modes and their role in our search for new physics. We also briefly discuss direct CP violation in rare B decays and the rare kaon decays $K^+\to π^+ν\barν$ and $K_L \to π^0 ν\barν$, which offer complementary opportunities for precision flavour physics.
We propose a novel method of measuring the CKM matrix element V_ub, via inclusive B decays to "wrong sign" charm. This process is mediated by the quark level decay b -> u cbar s'. When normalized to the inclusive semileptonic decay rate, the theoretical expression is very well behaved, with small uncertainties from unknown quark masses and no leading renormalon ambiguity. We compute the decay rate for this process, including the leading perturbative and nonperturbative corrections.
A novel approach to reconstruct inclusive $\bar{B} \to X_{s} \ell^{+}\ell^{-}$ decays is presented. The method relies on isopsin symmetry to extrapolate the semi-inclusive signature $X_{b}\to K^{+} \ell^{+}\ell^{-} X$ to the fully inclusive rate in $B^{+}$ and $B^{0}$ decays. We investigate the possibility to measure branching fractions and other observables such as lepton universality ratios and $CP$ asymmetries. As a proof of concept, fast simulation is used to compare the $X_{b}\to K^{+} \ell^{+}\ell^{-} X$ signature with a fully inclusive approach. Several experimental advantages are seen …
We review recent experimental and theoretical developments in inclusive semileptonic B -> Xc l nu decays. In particular, we discuss the determination of |Vcb| and of the heavy quark masses through fits based on the Operator Product Expansion.
The huge datasets collected at the two B factories, Belle and BaBar, have made it possible to explore the radiative penguin process b --> s gamma, the electroweak penguin process b --> s l+ l- and the suppressed radiative process b --> d gamma in detail, all in exclusive channels and inclusive measurements. Theoretical tools have also advanced to meet or surpass the experimental precision, especially in inclusive calculations and the various ratios of exclusive channels. In this article, we review the theoretical and experimental progress over the past decade in the radiative and electroweak p…
I review some recent progress, leading to a substantial reduction in the number of non-perturbative parameters, in the calculation of inclusive quarkonium decay widths in the framework of non-relativistic effective field theories.
We give a status report on inclusive rare B decays, highlighting recent developments and open problems. We focus on the decay modes $B \to X_{s,d} γ$, $ B \to X_s \ell^+\ell^-$ and $B \to X_s ν\bar ν$ and on their role in the search for new physics. Most of the inclusive rare B decays are important modes of flavour physics due to the small hadronic uncertainties. They can be regarded as laboratories to search for new physics. We collect the experimental data already available from CLEO and the $B$ factories BABAR and BELLE. We review the NLL and NNLL QCD calculations of the inclusive decay rat…
We calculate the total and differential decay rates for the semi-inclusive nonleptonic decays $B\to D_s^{(*)} X_q$ ($q=c$ or $u$) under the factorization hypothesis. The initial bound state effect is treated using the light-cone expansion and the heavy quark effective theory. We investigate the contribution of the penguin amplitude for the decay mode $B\to D_s^{(*)} X_c$ and find that it is small but non-negligible. The resulting decay rates for $B\to D_s^{(*)} X_c$ agree with the measurements. The use of the decay mode $B\to D_s^{(*)} X_u$ to determine $|V_{ub}|$ is discussed.
Based on the non-relativistic QCD factorization formalism, we calculate the bottomonium ground state, $η_b$, inclusive charm decays at the leading order in the strong coupling constant $α_s$ and quarkonium internal relative velocity $v$. The inclusive charm pair production in $η_b$ decay is mainly realized through $η_b \to c \bar{c} g$ process, where the charm and anti-charm quarks then dominantly hadronize into charmed hadrons. The momentum distributions of the final states are presented. In this work, we also calculate the $J/ψ$ inclusive production rate in the $η_b$ decays, where the color-…
The availability of branching fractions for a large majority of $D_s$ decays permits the prediction of inclusive branching fractions. This is achieved with the help of a modest amount of input from an isospin statistical model applied to non-resonant multibody $D_s$ decays. A systematic uncertainty in these mostly small branching ratios is estimated by comparing predictions of this model with those of a model involving quark-antiquark pair production. The calculated inclusive branching fractions can be compared with data (for example, from a large sample of $D_s^+ D_s^{*-} + D_s^{*+} D_s^-$ ob…
In this article, we review the theory and the experimental status of inclusive semileptonic B meson decays B -> Xc l nu. Based on these inputs, we present the latest determination of the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element |V_cb| and of the b-quark mass m_b, obtained by the Heavy Flavor Averaging Group (HFAG).
SIDIS-RC EvGen is a C++ standalone Monte-Carlo event generator for studies of semi-inclusive deep inelastic scattering (SIDIS) processes at medium to high lepton beam energies. In particular, the generator contains binary and library components for generating SIDS events and calculating cross sections for unpolarized or longitudinally polarized beam and unpolarized, longitudinally or transversely polarized target. The structure of the generator incorporates transverse momentum-dependent parton distribution and fragmentation functions, whereby we obtain multi-dimensional binned simulation resul…
We discuss the possibility of extracting |V_{ub}| from various spectra of inclusive B decays, without large systematic errors which usually arise from having to model the Fermi motion of the heavy quark. This strategy can be applied to the electron energy spectrum, as well as the hadronic mass spectrum. Modulo violation of local hadron-parton duality, the theoretical error in the extraction is estimated to be less than 10%.
We present predictions for the inclusive production of leptons ($e^{\pm},μ^{\pm}$) originating from charm and bottom-hadrons at the CERN LHC in the general-mass variable-flavor-number scheme at next-to-leading order. Detailed numerical results are compared to data of the CMS, ATLAS and ALICE collaborations.
We consider the possibility of observing CP violation in quasi-inclusive decays of the type $B^-\to K^- X$, $B^-\to K^{*-} X$, $\bar B^0\to K^- X$ and $\bar B^0\to K^{*-} X$, where $X$ does not contain strange quarks. We present estimates of rates and asymmetries for these decays in the Standard Model and comment on the experimental feasibility of observing CP violation in these decays at future $B$ factories. We find the rate asymmetries can be quite sizeable.
Using information on B-meson fragmentation functions from CERN LEP 1 and adopting the nonrelativistic QCD factorization formalism proposed by Bodwin, Braaten, and Lepage, we predict the transverse-momentum distribution of J/psi mesons originating from the inclusive decays of b hadrons produced in p p-bar collisions at the Fermilab Tevatron. We determine the relevant colour-octet charmonium matrix elements from fits to CDF data on prompt charmonium hadroproduction and to CLEO data on charmonium production from B-meson decay. Our predictions are found to agree well with recent CDF and D0 data.
We estimate the heavy quark effective theory parameter λ_1 from inclusive semileptonic B-meson decay spectrum. By using recent CLEO double lepton tagging data of B -> X e nu, which shows the lepton momentum as low as 0.6 GeV, we extracted λ_1 \sim -0.58 GeV^2. We also derived \barΛ\sim 0.46 GeV and |V_{cb}| = 0.041 \pm 0.002.
Inclusive semileptonic decays of beauty baryons are studied using the heavy quark expansion to ${\cal O}(1/m_b^3)$, at leading order in $α_s$. The case of a polarized decaying baryon is examined, with reference to $Λ_b$. An extension of the Standard Model effective Hamiltonian inducing $b \to U \ell {\bar ν}_ \ell$ transitions ($U=u,\,c$ and $\ell=e,\,μ,\,τ$) is considered, which comprises the full set of D=6 semileptonic operators with left-handed neutrinos. The effects of the new operators in several observables are described.
QED radiative effects in semi-inclusive deep-inelastic scattering: traditional and factorized approaches
Duke University（杜克大学）；Triangle Universities Nuclear Laboratory（三角大学核实验室）；Institute for Nuclear Problems of Belorussian State University（白俄罗斯国立大学核问题研究所）；Mississippi State University（密西西比州立大学）；Indiana University（印第安纳大学）；Shandong University（山东大学）；Institute of Modern Physics, Chinese Academy of Sciences（中国科学院近代物理研究所）；Jefferson Lab（杰斐逊实验室）
