Peter Zweber
Overconstraining the CKM unitarity triangle with precision measurements of its angles continues to test the validity of the Standard Model. One of these angles, gamma/phi_3, has been measured by studying B+- -> D K+- decays, where D = D0 or D0-bar. I present recent results of hadronic D decays which will improve the sensitivity of gamma/phi_3 measurements.
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The asymmetric B-factories have provided valuable information on CP violation so far. In particular, one of the angles of the Unitarity Triangle, phi1(=beta), has been measured by several approaches. Since FPCP2004, some measurements have been updated and improved. In this letter, the latest status of phi1 measurements, performed at BaBar and Belle experiments usgin B -> charm/charmonium decays, are reported.
Parameters for linac-ring type e^{-}e^{+} colliders with sqrt(s)=1020 MeV (phi factory), 3770 MeV (charm factory) and 4.2 GeV (tau factory) are discussed. It is shown that luminosities of the order of 10^{34} cm^{-2}s^{-1} can be achieved.
We present measurements of time-dependent CP violation parameters in B0 --> K0 PI0, B0 --> Ks Pi+ Pi- and B0 --> Ks K+ K- decays. The latter two are extracted using time-dependent Dalitz plot analyses. These results are obtained from a large data sample that contains 657 x 10^6 BBbar pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider.
We present preliminary measurements of branching fractions and CP-asymmetry parameters in two- and three-body charmless hadronic B decays. The available data sample consists of 227 million Upsilon(4S) B decays collected with the BABAR detector at the PEP-II asymmetric-energy e+e- collider at SLAC. We establish the observation of the decays B --> pi0 pi0 and B0 --> K0K0bar and constrain the CKM angle alpha with a full SU(2) isospin analysis in the B --> pi pi system and with a B0 --> pi+ pi- pi0 time-dependent Dalitz plot analysis.
Using the data sample of 10.5 fb-1 collected by the Belle detector, we searched for two-body charmless decays involving vector mesons. The clear signal signature of B+ -> phi K+ is seen and its branching fraction is measured to be (1.39+.32-.30 +- 0.2) X 10-5. The evidence for B+ -> rho pi+, B0 -> rho- pi+ and B+ -> phi K*+ is reported and their branching fractions are determined. No significant signals are observed for B0 -> phi K0S, -> phi K*0, -> rho- K+, B+ -> rho K+, -> omega pi+ and -> omega K+ only the 90% C.L. upper limits are given.
We present results of B -> vector-vector (VV) and B -> vector-axial vector (VA) decays B0 -> phi X (X = phi, rho+ or rho0), B+ -> phi K(*)+, B0 -> K*K*, B0 -> rho+b_1- and B+ -> K*0a_1+. The largest dataset used for these results is based on 465 * 10^6 Y(4S) -> BB decays, collected with the BABAR detector at the PEP-II B meson factory located at the Stanford Linear Accelerator Center (SLAC).
We search for B meson decays into two-body combinations of eta, eta', omega, and phi mesons from 89 million B B-bar pairs collected with the BaBar detector at the PEP-II asymmetric-energy e+e- collider at SLAC. We find the branching fraction BF(B0 -> eta omega) = (4.0^{+1.3}_{-1.2} +- 0.4) x 10^-6 with a significance of 4.3 sigma. For all the other decay modes we set the following 90% confidence level upper limits on the branching fractions, in units of 10^-6 : BF(B0 -> eta eta)<2.8, BF(B0 -> eta eta')<4.6, BF(B0 -> eta' eta')<10, BF(B0 -> eta'omega)<2.8, BF(B0 -> eta phi)<1.0, BF(B0 -> eta' p…
The formalism for extracting the CKM parameter $V_{cd}$ from $νN$ production of charm is discussed in some detail. The various model assumptions needed are clearly pointed out. A direct determination from neutrino induced dimuon production requires $νN$ charm production data, $% νN$ charm hadronization data, and the semi-muonic branching ratios for charmed hadrons. Hadronization data from FNAL E531 is re-analyzed to take advantage of better-determined properties of the charmed hadrons. A small bias in the original published result is removed. Neutrino induced charm fragmentation is compared to…
Penguin transitions play a key role in the search of New Physics hints in the heavy flavor sector. During the last decade CDF has been exploring this opportunity with a rich study of two--body charmless decays of neutral B mesons into charged final--state particles. After briefly introducing the aspects of this physics peculiar to the hadron collision environment, I report on two interesting results: the first polarization measurement of the B^0_s --> phi phi decay and the update of the B^0(_s) --> h^+h'^- decays analysis.
Using 230.2 fb^(-1) of e+e- annihilation data collected with the BABAR detector at and near the peak of the Y(4S) resonance, 489 +/- 55 events containing the pure leptonic decay D_s^+ --> mu^+ nu_mu have been isolated in charm-tagged events. The ratio of partial widths Gamma(D_s^+ --> mu^+ nu_mu)/Gamma(D_s^+ --> phi pi^+) is measured to be 0.143 +/- 0.018 +/- 0.006 allowing a determination of the pseudoscalar decay constant f_{D_s} = (283 +/- 17 +/- 7 +/- 14) MeV. The errors are statistical, systematic, and from the D_s^+ --> phi pi^+ branching ratio, respectively.
Using a large sample of charm semileptonic decays collected by the FOCUS photoproduction experiment at Fermilab, we present new measurements of two semileptonic branching ratios. We obtain values of D+ to K*munu/k2pi = 0.602 +/- 0.010 +/- 0.021 and Ds to phimunu/phipi = 0.54 +/- 0.033 +/- 0.048. Our result D+ result includes the effects of s-wave interference.
The observation of a narrow structure near the J/psi phi threshold in exclusive B+ to J/psi phi K+ decays produced in p-pbar collisions at sqrt(s) = 1.96 TeV is reported. A signal of 19 +- 6(stat) +- 3(syst) events, with statistical significance of 5.0 standard deviations, is seen in a data sample corresponding to an integrated luminosity of 6.0 invfb, collected by the CDF II detector. The mass and natural width of the structure are determined to be m = 4143.4 + 2.9 - 3.0(stat) +- 0.6(syst) MeV and Gamma = 15.3 + 10.4 - 6.1(stat) +- 2.5(syst) MeV, consistent with the previous measurements repo…
We report the observation of the decay mode B -> phi phi K based on an analysis of 78 fb^{-1} of data collected with the Belle detector at KEKB. This is the first example of a b -> s sbar s sbar s transition. The branching fraction for this decay is measured to be B(B^{+-} -> phi phi K^{+-}) = (2.6 ^{+1.1}_{-0.9} +- 0.3) x 10^{-6} for a phi phi invariant mass below 2.85 GeV/c^2. Results for other related charmonium decay modes are also reported.
We present preliminary measurements of the branching fractions for charmless hadronic decays of B mesons into two-body final states with kaons, pions and a phi resonance. The measurements are based on a data sample of approximately 23 million B-anti-B pairs collected by the BABAR detector at the PEP-II asymmetric B Factory at SLAC.
The Belle experiment has measured branching fractions and CP asymmetries for the charmless decays B0->pi+pi- and B0->rho+-pi-+. From these measurements, constraints upon the CKM angle phi_2 can be obtained. These constraints indicate that phi_2 is around 100 degrees.
The Belle and BaBar experiments have measured branching fractions and CP asymmetries in the charmless decay modes B0->pi+pi-, B0->rho+pi-/rho-pi+, and B0->rho+rho-. From these measurements, constraints upon the CKM angle phi_2 can be obtained. These constraints consistently indicate that phi_2 is around 100 degrees.
We present the results of searches for B decays to charmless final states involving phi, fzero(980), and charged or neutral rho mesons. The data sample corresponds to 384 million BBbar pairs collected with the babar detector operating at the PEP-II asymmetric-energy epem collider at SLAC. We find no significant signals and determine the following 90% confidence level upper limits on the branching fractions, including systematic uncertainties: B(B0->phiphi) < 2.0 x 10^-7, B(B+->phirho+) < 30 x 10^-7, B(B0->phirho0) < 3.3 x 10^-7, B(B0-phif0) x B(f0->pi+pi-) < 3.8 x 10^-7, and B(B0->f0f0) x B(f0…
We report on preliminary measurements of time-dependent CP-violation asymmetries in charmless neutral B meson decays to K+K-K0 (including resonant decays phiK0 and f0K0), eta'K0, pi0K0s, K0sK0sK0s, K0sK0s, rho0K0s, omegaK0s. The results are obtained from a data sample of up to 347 million BBbar pairs produced by e+e- annihilation at the Y(4S) resonance collected with the BaBar detector at the PEP-2 asymmetric-energy B-meson Factory at SLAC.
Quantum correlations in $ψ(3770) \to D^0\bar{D}^0$ provide unique access to information about strong phase differences. Precision determination of the CKM phase $γ/ϕ_3$ via $B \to D K$ decays depends upon constraints on charm mixing amplitudes, measurements of doubly-Cabibbo suppressed amplitudes and relative phases, and studies of correlated charmed meson decays tagged by flavor or CP eigenstates. CP-tagged $D^0 \to K^-π^+π^-π^+$ decays and CP-tagged $D^0 \to K^0_Sπ^+π^-$ Dalitz plots are only available at CLEO-c. Using the 818 pb$^{-1}$ CLEO-c data sample produced by the Cornell Electron Sto…
We report the results of some recent E791 charm analyses. They include: 1) a search for rare and forbidden decays, 2) measurements of form factors for D+ --> K*,l,nu and Ds --> phi,l,nu, and 3) Ds and D0 lifetime measurements including the lifetime difference between D0-->Kpi and D0-->KK. The latter is the first direct search for a possible lifetime difference that could contribute to D0-D0bar mixing.
I present recent results of measurements of branching fractions and CP-violating asymmetries in B0, Bs, and Lambda_B two-body charmless decays at the upgraded Collider Detector at the Fermilab Tevatron. Measurements of rates of flavor-changing neutral current B0, Bs -->mu+mu- and B+/B0/Bs --> mu+mu- K+/K*0/phi decays are also reported. The results are extracted from samples corresponding to time-intergrated luminosities ranging from 0.78 to 1 fb-1.
The latest experimental results in charmless B decays are presented with a focus on CP violation measurements. These include the first observation of CP violation in B_s decays, evidence for CP violation in charmless three-body B+ decays, branching fraction measurements of B+ --> ppK+ decays and the first observation of the decay B_s --> phi K*0 from LHCb, a comparison of B+ --> K+K-K+ CP violation measurements between LHCb and BaBar, and the first evidence for the decay B0 --> K+K-pi0 obtained by Belle.
The first measurement of B(0->phi X0) and an upper limit for B(D+->phi X+) are determined from 22.3 pb-1 of e+e- annihilation data at a C. M. energy of 4.03 GeV. The data were recorded by the Beijing Spectrometer (BES) at BEPC. A recoil charge method is applied for the first time to charm threshold data to determine the charge of the D meson in the recoil from 9054+-309+-416 reconstructed D0, D+ mesons. The branching fractions B(D->phiX0) =(1.71+0.76-0.71+-0.17)%, and B(D+->phiX+) <1.8% are determined from 10 events with a reconstructed D and a recoiling phi. In addition, a 90% C.L. upper limi…
We have measured the form factor ratios r_V = V(0)/A_1(0) and r_2 = A_2(0)/A_1(0) for the decay D_s^+ -> phi ell^+ nu_ell, phi -> K^+ K^-, using data from charm hadroproduction experiment E791 at Fermilab. Results are based on 144 signal and 22 background events in the electron channel and 127 signal and 34 background events in the muon channel. We combine the measurements from both lepton channels to obtain r_V = 2.27 +- 0.35 +- 0.22 and r_2 = 1.57 +- 0.25 +- 0.19.
We present the first evidence of the decay mode $B_s \to ϕϕ$ and a measurement of partial width and direct CP asymmetry for the $B^+ \to ϕK^+$ decay using $180 pb^{-1}$ of data collected by the CDFII experiment at the Fermilab Tevatron collider. We measure: $BR (\phiphi) = (1.4 \pm 0.6(stat.) \pm 0.2(syst.) \pm 0.5(\BR)) \cdot 10^{-5}$, where the last error is due to the uncertainty on the $B_s \to J/ψϕ$ branching ratio used as normalization, $BR (ϕk) = (7.2 \pm 1.3(stat.) \pm 0.7(syst.)) \cdot 10^{-6}$ and $\ACP(phi k) = -0.07 \pm 0.17 (stat.) \ase{0.06}{0.05} (syst.)$. We also briefly discus…
We report on a search for the exclusive two-body charmless hadronic B meson decays B-> eta' rho, B-> eta' K*, B-> eta' phi, B-> eta' omega and B->eta' eta('). The results are obtained from a data sample containing 535 x 10^6 BBbar pairs that were collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+ e- collider. We find no significant signals and report upper limits in the range 0.5-6.5 x 10^{-6} for all of the above decays.
We present measurements of the branching ratio and of the polarization amplitudes in charmless Bs to Phi Phi decays using data corresponding to 2.9/fb of integrated luminosity, collected by the CDF experiment at the Tevatron. The branching ratio in Bs to Phi Phi decays is measured relative to the normalization mode Bs to J/Psi Phi$ to be B(Bs to Phi Phi)/B(Bs to J/Psi Phi) = [1.78 +/- 0.14 (stat) +/- 0.20 (syst)] x 10^{-2}. Using the experimental value of B(Bs to J/Psi Phi) we determine the Bs to Phi Phi branching ratio B(Bs to Phi Phi) = 2.40 +/- 0.21(stat) +/- 0.27(syst) +/- 0.82 (BR)] x 10^…
We have studied two-body charmless hadronic decays of $B$ mesons into the final states phi K and phi K^*. Using 9.7 million $B\bar{B}$ pairs collected with the CLEO II detector, we observe the decays B- -> phi K- and B0 -> phi K*0 with the following branching fractions: BR(B- -> phi K-)=(5.5 +2.1-1.8 +- 0.6) x 10^{-6} and BR(B0 -> phi K*0)=(11.5 +4.5-3.7 +1.8-1.7) x 10^{-6}. We also see evidence for the decays B0 -> phi K0 and B- -> phi K*-. However, since the statistical significance is not overwhelming for these modes we determine upper limits of <12.3 x 10^{-6} and <22.5 x 10^{-6} (90% C.L.…
We analyze nonleptonic $B_s$ decays to a charmonium state and a light meson, induced by the $b \to c {\bar c}s$ transition, which are useful to access the $B_s$-${\bar B}_s$ mixing phase $β_s$. We use generalized factorization and $SU(3)_F$ symmetry to relate such modes to correspondent $B$ decay channels. We discuss the feasibility of the measurements in the various channels, stressing the importance of comparing different determinations of $β_s$ in view of the hints of new physics effects (NP) recently emerged in the $B_s$ sector. Finally, adopting a general parametrization of NP contributio…
We measure the inclusive branching fractions of charm mesons into three mesons with large s-anti-s content, namely the eta, eta' and phi. Data were accumulated with the CLEO-c detector. For D0 and D+ rates, we use 281/pb taken on the psi(3770) resonance, and for Ds+ rates, we use 195/pb taken at 4170 MeV. We find that the production rates of these particles are larger in Ds+ decays than in D0 and D+ decays. The phi rate, in particular, is 15 times greater. These branching fractions can be used to measure Bs yields either at the Upsilon(5S) resonance or at hadron colliders.
We report the results of a search for flavor-changing neutral current, lepton-flavor, and lepton-number violating decays of the 3 and 4-body decay modes of D0 (and its antiparticle) containing muons and electrons. Using data from Fermilab charm hadroproduction experiment E791, we examine modes with two leptons and either a Rho(0), Kstar, or Phi vector meson or a non-resonant Pi Pi, K Pi, or K K pair of pseudoscalar mesons. No evidence for any of these decays is found. Therefore, we present branching-fraction upper limits at 90% confidence level for the 27 decay modes examined (18 new).
We report on measurements of differential cross sections d sigma/d p_t for prompt charm meson production in p anti-p collisions at s**(1/2) = 1.96 TeV using 5.8 +/- 0.3 pb-1 of data from the CDF II detector at the Fermilab Tevatron. The data are collected with a new trigger that is sensitive to the long lifetime of hadrons containing heavy flavor. The charm meson cross sections are measured in the central rapidity region |y| \leq 1 in four fully reconstructed decay modes: D0 --> K- pi+, D*+ -> D0 pi+, D+ --> K- pi+ pi+, D+_s--> phi pi+, and their charge conjugates. The measured cross sections …
Fermilab experiment E791 studied weak decays of D+, D_s, and D^0 mesons produced in collisions of 500 GeV/c negative pions with Pt and C targets. The experiment collected over 200,000 fully reconstructed charm decays. Four recent results are discussed here: (a) measurement of the form factor ratios V/A_1, A_2/A_1, and A_3/A_1 in D->K*-l-nu and Ds->phi-l-nu decays; (b) measurement of the difference in decay widths $ΔΓ$ between the two D^0/D^0-bar mass eigenstates; (c) search for rare and forbidden D decays to dilepton final states; and (d) search for a ``Pentaquark,'' a bound state of c-bar-suu…
Recent CLEO results on beauty and charm meson decays presented at the International Conference on Flavor Physics (ICFP2001) are discussed. The results include exclusive rare B decays (B to PP, PV, VV, \phiK^(*), l^+l^-K^(*)), inclusive b to s γ, and CP violation measurements in beauty and charm mesons. Preliminary results on rare B decays using CLEO III data are also included.
We report results on the Dalitz analysis of three-body charmless B+=>K+Pi+Pi- 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+ => f0(980)K+, B+ => K*_0(1430)^0 Pi+, and to vector-pseudoscalar states: B+ => K*(892)^0 Pi+, B+ => rho(770)K+, B+ => phi(1020)K+ are presented. Upper limits on decays to some pseudoscalar-tensor final states are reported. We also report the measurement of the B+ => chi_c0 K+ branching fraction in two chi_c0 decays channels: chi_c…
We present the first evidence of charmless decays of the $B_s^0$ meson, the decay \phiphi, and a measurement of the Branching Ratio $\BR(\phiphi)$ using $180 {\rm pb}^{-1}$ of data collected by the \cdfii experiment at the Fermilab Tevatron collider. In addition, the BR and direct CP asymmetry for the \phik\ decay are measured. We obtain: $\BR (\phiphi) = (14 \ase{6}{5}(stat.) \pm 6(syst.)) \times 10^{-6}$, $\BR (\phik) = (7.6 \pm 1.3(stat.) \pm 0.6(syst.)) \times 10^{-6}$, and $\ACP(\phik) = -0.07 \pm 0.17 (stat.) \ase{0.03}{0.02} (syst.)$. Both decays are governed in the Standard Model by se…
We present a review of the measurements of the CKM angle beta (phi_1) by the BaBar and Belle experiments at the asymmetric-energy e+e- B Factories PEP-II and KEKB. The angle beta (phi_1) is measured by time-dependent CP analyses of neutral B meson decays in a Upsilon(4S)->BBbar system, where one B meson is fully reconstructed in a final state that can be accessed to by both B0 and B0bar, usually a CP eigenstate. This angle has been measured at a high precision through B0-> (ccbar)K0 channels. We also review another tree-dominated decay B0-> D(*)0 h0 (h0 = pi0, eta^{'}, omega); tree decays with…
We exploit the quantum coherence between pair-produced D0 and D0B in psi(3770) decays to make a first determination of the relative strong phase differences between D0--> K0Spi+pi- and D0B--> K0Spi+pi-, which are of great importance in determining the CKM angle gamma/phi3 in B- --> D0 (D0B) K- decays. Using 818 1/pb of e+e- collision data collected with the CLEO-c detector at Ecm = 3.77 GeV, we employ a binned Dalitz-plot analysis of K0S pi+pi- and K0Lpi+pi- decays recoiling against flavor-tagged, CP-tagged and K0Spi+pi- tagged events to determine these strong phase differences.
The knowledge of charm production asymmetries is an important prerequisite for many of the possible searches for CP violation in charm. Measurements of these asymmetries at hadron colliders can also help to improve our understanding of QCD. These proceedings review existing measurements and discuss some of the experimental challenges of determining charge asymmetries at the per-mille level.
We present a new determination of the Ds decay constant, f_{Ds} using 5 million continuum charm events obtained with the CLEO II detector. Our value is derived from our new measured ratio of widths for Ds -> mu nu/Ds -> phi pi of 0.173+/- 0.021 +/- 0.031. Taking the branching ratio for Ds -> phi pi as (3.6 +/- 0.9)% from the PDG, we extract f_{Ds} = (280 +/- 17 +/- 25 +/- 34){MeV}. We compare this result with various model calculations.
We describe searches for B meson decays to the charmless vector-vector final states omega K*, omega rho, omega omega, and omega phi with 233 times 10^{6} BB pairs produced in e+e- annihilation at sqrt{s}=10.58 GeV. We also search for the vector-scalar B decay to omega f_0. We measure the following branching fractions in units of 10^{-6}: BR(B0 --> omega K*0) = 2.4 +/- 1.1 +/- 0.7 (<4.2), BR(B+ --> omega K*+) = 0.6 {+1.4}_{-1.2} {+1.1}_{-0.9} (<3.4), BR(B0 --> omega rho0) = -0.6 +/- 0.7 {+0.8}_{-0.3} (<1.5), BR(B+ --> omega rho+) = 10.6 +/- 2.1 {+1.6}_{-1.0}, BR(B0 --> omega omega) = 1.8 {+1.3}…
We present two recent results obtained by the CDF collaboration at the Tevatron collider. New Cabibbo suppresed B_s decay modes have been observed using 5.9 inverse fb of data: B_s-> J/psi Ks and B_s->J/psi K*0. We report also on masurement of the ratios of the branching ratios (BR) of the new modes to those of the B^0-meson to the same final states: BR(B_s->J/psi K*0)/BR(B^0->J/psi K*0) = 0.062 \pm 0.009 (stat.) \pm 0.025 (sys.) \pm 0.008 (frag.) and BR(B_s->J/psi Ks)/BR(B^0->J/psi Ks) = 0.041 \pm 0.007 (stat.) \pm 0.004 (sys.) \pm 0.005 (frag.). Then we discuss the first polarization measure…
In this article I report on new and updated measurements of the CP-violating parameter beta (phi_1), which is related to the phase of the Cabibbo-Kobayashi-Maskawa (CKM) quark-mixing matrix of the electroweak interaction. Over the past few years, beta has become the most precisely known parameter of the CKM unitarity triangle that governs the B system. The results presented here were produced by the two B factories, BaBar and Belle, based on their most recent datasets of over 600 million BB events combined. The new world average for sin(2beta), measured in the theoretically and experimentally …
Rare charm decays offer the unique possibility to explore flavour-changing neutral-currents in the up-sector within the Standard Model and beyond. Due to the lack of effective methods to reliably describe its low energy dynamics, rare charm decays have been considered as less promising for long. However, this lack does not exclude the possibility to perform promising searches for New Physics per se, but a different philosophy of work is required. Exact or approximate symmetries of the Standard Model allow to construct clean null-test observables, yielding an excellent road to the discovery of …
With growing datasets collected by the CDF II experiment, studies of the spectroscopy of mesons containing heavy quarks become more exciting. The CDF experiment has good capabilities in both charm and bottom sector. This capability allowed also to contribute to the study of the zoo of states called X,Y,Z. In this area we present a recent update of the mass measurement of X(3872). The result m(X(3872)) = 3871.61 +- 0.16 +- 0.19 MeV is currently the most precise measurement in the world. In addition, we report evidence for a new narrow resonance, Y(4140), the first to be seen in the J/psi phi de…
Recent evidence for direct CP violation in non-leptonic charm decays cannot be easily accommodated within the Standard Model (SM). On the other hand, it fits well in new physics models generating CP violating Delta C=1 chromomagnetic dipole operators. We show that in these frameworks sizable direct CP asymmetries in radiative D to P+ P- gamma decays (P=pi,K), with M_PP close to the rho or the phi peak, can be expected. Enhanced matrix elements of the electromagnetic dipole operators can partly compensate the long distance dominance in these decays, leading to CP asymmetries of the order of sev…
We report results of a search for CP violation in the singly Cabibbo-suppressed decays D+ -> K- K+ pi+, phi pi+, K*(892)0 K+, and pi- pi+ pi+ based on data from the charm hadroproduction experiment E791 at Fermilab. We search for a difference in the D+ and D- decay rates for each of the final states. No evidence for a difference is seen. The decay rate asymmetry parameters A(CP), defined as the difference in the D+ and D- decay rates divided by the sum of the decay rates, are measured to be: A(CP)(K K pi) = -0.014 +/- 0.029, A(CP)(phi pi) = -0.028 +/- 0.036, A(CP)(K*(892) K) = -0.010 +/- 0.050…
I discuss new results on absolute branching ratios of charm mesons into specific exclusive final states, Cabibbo suppressed decay rates, inclusive decays to $s\bar{s}$ mesons, limits on D^0 anti-D^0 mixing, CP violation and T violation. Preliminary results from CLEO-c now dominate the world average absolute branching fractions. For the most important normalization modes involving D^0 and D^+, the averages are B(D^0 -> K^- pi^+ = (3.87 +/- 0.06)%, and B(D^+ -> K^- pi^+ pi^+)= (9.12 +/- 0.19)%. For the Ds^+ CLEO-c measures B(Ds+ -> K^- K^+ pi^+)=(4.54^{+0.44}_{-0.42} =/- 0.25)%. Using this rate,…
We present preliminary measurements of CP-violating asymmetries in B decays. These include new results on the CKM angle alpha based on studies of the decay B -> rho+ rho- and several charmonium and hadronic penguin modes, sensitive to the CKM angle beta, including results on B -> phi K0S, B -> K+K-K0, B -> eta' K0S, B -> f0 K0, and B -> pi0 K0S. We also report on several of results related to the extraction of gamma and (2*beta+gamma) and present limits on CPT violation in B decays.
The quark model does not exclude states composed of more than three quarks, like pentaquark systems. Controversial evidence for such states has been published in the last years, in particular: for a strange pentaquark Theta(1540)+; for a double-strange state, the Xi(1862)--, subsequently called Phi(1860)--; and for a charmed state, the Theta_c(3100)^0. If confirmed, a full pentaquark family might exist; such pentaquark states could be produced in e+e- annihilations near the Z energy. In this paper a search for pentaquarks is described using the DELPHI detector at LEP, characterized by powerful…
Inputs for the $γ$ measurements from BESIII
本文介绍了BESIII实验为测量CKM角$γ$提供的关键输入，指出利用其量子关联数据样本可高度抑制来自粲区的$γ$不确定度，从而辅助检验CKM矩阵幺正性与寻找新物理。
We report the results of a precise measurement of the Ds meson lifetime based on 1662 +/- 56 fully reconstructed Ds -> phi pi decays, from the charm hadroproduction experiment E791 at Fermilab. Using an unbinned maximum likelihood fit, we measure the Ds lifetime to be 0.518 +/- 0.014 +/- 0.007 ps. The ratio of the measured Ds lifetime to the world average D0 lifetime is 1.25 +/- 0.04. This result differs from unity by six standard deviations, indicating significantly different lifetimes for the Ds and the D0.
We explore the possibility of experimentally detecting a predicted $h_1 ~[I^G(J^{PC})=0^-(1^{+-})]$ state of hidden charm made out from the $D^* \bar D^*$ interaction. The method consists in measuring the decay of X(4660) into $ηD^* \bar D^*$, determining the binding energy with respect to the $D^* \bar D^*$ threshold from the shape of the $D^* \bar D^*$ invariant mass distribution. A complementary method consists in looking at the inclusive $X(4660) \to ηX$ decay, searching for a peak in the $X$ invariant mass distribution given by the missing X(4660), $η$ mass. We make calculations to determ…
Charming Darwin: the evolution of QCD parameters across different species
本文研究利用BESIII单举粲强子衰变谱矩测量HQE参数（动能、色磁矩、达尔文项）的可行性，并探讨其对确定$|V_{cs}|$的灵敏度。
Systematic study of light and charm meson M1 radiative transitions
本研究结合有效质量方案与非相对论势模型，系统研究轻介子与粲介子的M1辐射跃迁，分析标度依赖效应，明确高阶QCD修正对衰变宽度的关键作用。
Within the framework of perturbative QCD approach based on $\mathbf{k_T}$ factorization, we investigate the charmless decay mode $B \to K_0^*(1430)ϕ$. Under two different scenarios (S1 and S2) for the description of scalar meson $K_0^*(1430)$, we explore the branching fractions and related CP asymmetries. Besides the dominant contributions from the factorizable emission diagrams, penguin operators in the annihilation diagrams could also provide considerable contributions. The central values of our predictions are larger than those from the QCD factorization in both scenarios. Compared with the…
Recent measurements of B hadron properties carried out in sqrt(s)=1.96 TeV p/p-bar collisions at the Tevatron are reviewed. Included are measurements of the Bc+ meson lifetime, using J/psi+l+X final states, and the mass, using J/psi+pi final states, a flavor specific measurement of the Bs0 lifetime in Ds+pi+X decays, simultaneous measurements of the Bs0 lifetime and lifetime difference in J/psi+phi decays, the first direct evidence and mass measurements of the Xi_b- baryon, and measurements of the polarization of 1S charmonium. For all measurements, charge conjugate modes are included.
I report recent measurements in b-hadron decays reconstructed in the full data set of \sqrt{s} = 1.96 TeV proton-antiproton collisions collected by the CDF experiment at the Tevatron. These include the final CDF results on: measurements of CP asymmetries in two-body charmless decays of the Bd, Bs, and Λ^0_b hadrons; bounds on the Bs mixing phase and on the decay width difference of Bs mass eigenstates; and updated measurements of branching ratios of Bs->Jpsi Phi and Bs->Ds(*)Ds(*) decays. All measurements are among the most precise from a single experiment and in agreement with the standard mo…
We report results of the Dalitz analysis of the three-body charmless B->K+pi+pi- and B->K+K+K- decays based on a 140fb^{-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 pi+, and to vector-pseudoscalar states: B-> K^*(892)^0 pi+, B-> rho^0 K+, B-> phi K+ are presented. Upper limits on decays to some pseudoscalar-tensor final states are reported. We also report the new measurement of the B-> chi_c K+ branching fraction in two chi_c decay channels: chi_c-> pi+ pi- and …
We describe a search for hadronic decays of the Y(1S), Y(2S), and Y(3S) resonances to the exclusive final states rho pi, K*(892) Kbar, rho a2(1320), omega f2(1270), phi f2'(1525), K*(892) K2*(1430)bar, b1(1235) pi, K1(1270) Kbar, and K1(1400) Kbar. Upper limits at 90% CL are set for all these decays from all three resonances below 33x10**-6; in particular, B(Y(1S)--> rho pi) < 4x10**-6 is the smallest such upper limit. For two modes, a branching fraction of zero can be ruled out with a statistical significance of more than 5sigma: B(Y(1S) --> phi f2'(1525)) = (7 +3-2(stat) +-1(syst)) x 10**-6 …
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