ترغب بنشر مسار تعليمي؟ اضغط هنا

Studies of beauty baryon decays to $D^0 p h^-$ and $Lambda_c^+ h^-$ final states

130   0   0.0 ( 0 )
 نشر من قبل Anton Poluektov
 تاريخ النشر 2013
  مجال البحث
والبحث باللغة English




اسأل ChatGPT حول البحث

Decays of beauty baryons to the $D^0 p h^-$ and $Lambda_c^+ h^-$ final states (where $h$ indicates a pion or a kaon) are studied using a data sample of $pp$ collisions, corresponding to an integrated luminosity of 1.0 fb$^{-1}$, collected by the LHCb detector. The Cabibbo-suppressed decays $Lambda_b^0to D^0 p K^-$ and $Lambda_b^0to Lambda_c^+ K^-$ are observed and their branching fractions are measured with respect to the decays $Lambda_b^0to D^0 p pi^-$ and $Lambda_b^0to Lambda_c^+ pi^-$. In addition, the first observation is reported of the decay of the neutral beauty-strange baryon $Xi_b^0$ to the $D^0 p K^-$ final state, and a measurement of the $Xi_b^0$ mass is performed. Evidence of the $Xi_b^0to Lambda_c^+ K^-$ decay is also reported.



قيم البحث

اقرأ أيضاً

We report the result from the first search for $D^0$ decays to invisible final states. The analysis is performed on a data sample of 924 $rm{fb}^{-1}$ collected at and near the $Upsilon(4S)$ and $Upsilon(5S)$ resonances with the Belle detector at the KEKB asymmetric-energy $e^{+}e^{-}$ collider. The absolute branching fraction is determined using an inclusive $D^0$ sample, obtained by fully reconstructing the rest of the particle system including the other charmed particle. No significant signal yield is observed and an upper limit of $9.4times 10^{-5}$ is set on the branching fraction of $D^0$ to invisible final states at 90% confidence level.
We report measurements of the branching fractions of singly Cabibbo-suppressed decays $Lambda_c^+ to p eta$ and $Lambda_c^+ to p pi^0$ using the full Belle data sample corresponding to an integrated luminosity of 980.6 $rm fb^{-1}$. The data were col lected by the Belle detector at the KEKB $e^{+}$$e^{-}$ asymmetric-energy collider. A clear $Lambda_c^+$ signal is seen in the invariant mass distribution of $p eta$. The signal yield of the $Lambda_c^+ to p eta$ process is $7734 pm 263$; from this, we measure the ratio of branching fractions ${cal B}(Lambda_c^+ to p eta)/{cal B}(Lambda_c^+ to p K^- pi^+) = (2.258 pm 0. 077(rm stat. ) pm 0.136(rm syst. ))times 10^{-2}$, from which we infer the branching fraction ${cal B}(Lambda_c^+ to p eta) = (1.42 pm 0.05(rm stat.) pm 0.11(rm syst.)) times 10^{-3}$. In addition, no significant signal for $Lambda_c^+ to p pi^0$ is found so an upper limit on the branching fraction of ${cal B}(Lambda_c^+ to p pi^0)<8.0 times 10^{-5}$ at 90% credibility level is set, more than three times better than the best current upper limit.
Decays of $B^0$ and $B_{s}^0$ mesons to the charmless baryonic final states $p overline{p} h^+ h^{prime-}$, where $h$ and $h^prime$ each denote a kaon or a pion, are searched for using the LHCb detector. The analysis is based on a sample of proton-pr oton collision data collected at center-of-mass energies of $7$ and $8,$TeV, corresponding to an integrated luminosity of $3,$fb$^{-1}$. Four-body charmless baryonic $B_{s}^0$ decays are observed for the first time. The decays $B^0_{s}to p overline{p} K^+ K^-$, $B^0_{s}to p overline{p} K^pm pi^mp$, $B^0to p overline{p} K^pm pi^mp$ and $B^0to p overline{p} pi^+pi^-$ are observed with a significance greater than $5$ standard deviations; evidence at $4.1$ standard deviations is found for the $B^0to p overline{p} K^+ K^-$ decay and an upper limit is set on the branching fraction for $B^0_{s}to p overline{p} pi^+ pi^-$. Branching fractions in the kinematic region $m(p overline{p})<2850,$MeV$/c^2$ are measured relative to the $B^0 to J/psi (to p overline{p}) K^*(892)^0$ channel.
A study of $D^+pi^-$, $D^0 pi^+$ and $D^{*+}pi^-$ final states is performed using pp collision data, corresponding to an integrated luminosity of 1.0 $fb^{-1}$, collected at a centre-of-mass energy of 7 TeV with the LHCb detector. The $D_1(2420)^0$ r esonance is observed in the $D^{*+}pi^-$ final state and the $D^*_2(2460)$ resonance is observed in the $D^+pi^-$, $D^0 pi^+$ and $D^{*+}pi^-$ final states. For both resonances, their properties and spin-parity assignments are obtained. In addition, two natural parity and two unnatural parity resonances are observed in the mass region between 2500 and 2800 MeV. Further structures in the region around 3000 MeV are observed in all the $D^{*+}pi^-$, $D^+pi^-$ and $D^0 pi^+$ final states.
Dynamics and direct $CP$ violation in three-body charmless decays of charged $B$ mesons to a proton, an antiproton and a light meson (pion or kaon) are studied using data, corresponding to an integrated luminosity of 1.0$ {,fb}^{-1}$, collected by th e ${LHCb}$ experiment in $pp$ collisions at a center-of-mass energy of 7 TeV. Production spectra are determined as a function of Dalitz-plot and helicity variables. The forward-backward asymmetry of the light meson in the $pbar p$ rest frame is measured. No significant $CP$ asymmetry in $B^+ to p bar p K^+$ decay is found in any region of the Dalitz plane. We present the first observation of the decay $B^+ to kern 0.1embar{kern -0.1emLambda}(1520)(to K^+bar p)p$ near the $K^+bar p$ threshold and measure $mathcal{B}(B^+ to kern 0.1embar{kern -0.1emLambda}(1520)p)=(3.9^{+1.0}_{-0.9} (mathrm{stat})pm0.1 (mathrm{syst})pm0.3 (mathrm{BF}))times 10^{-7}$, where BF denotes the uncertainty on secondary branching fractions.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا