ترغب بنشر مسار تعليمي؟ اضغط هنا

Production and Decay of the Lambda_c Charmed Baryon from Fermilab E791

71   0   0.0 ( 0 )
 نشر من قبل Don Summers
 تاريخ النشر 2001
  مجال البحث
والبحث باللغة English
 تأليف B. Meadows




اسأل ChatGPT حول البحث

Results are presented for the 500 GeV/c pion production asymmetry and polarization of the Lambda_c (anti-Lanbda_c) charmed baryon from Fermilab experiment E791. An analysis of the decay to the p anti-K pi final state is described. Resonant sub-channel fractions and phases are given and possible resonant effects in the low mass p anti-K system discussed. Significant decay to Lambda_c --> Delta++ K- establishes for the first time the importance of a W exchange mechanism in charmed baryon decay.



قيم البحث

اقرأ أيضاً

95 - Carla Gobel 2001
We present recent results on light mesons based on Dalitz plot analyses of charm decays from Fermilab experiment E791. Scalar mesons are found to have large contributions to the decays studied, $D^+to K^-pi^+pi^+$ and $D^+, D_s^+topi^-pi^+pi^+$. From the $Kpipi$ final state, we find good evidence for the existence of the light and broad $kappa$ meson and we measure its mass and width. We also discuss recently published results on the 3$pi$ final states, especially the measurement of the $f_0$ parameters and the evidence for the $sigma$ meson from $D^+tosigmapi^+$. These results demonstrate the importance of charm decays as a new environment for the study of light meson physics.
Angular distribution of the final particles in the decay $Lambda_c^+to K^- , Delta (1232)^{++} to K^- , p , pi^+$ of the polarized charmed baryon is discussed. Asymmetries are proposed which allow for determination of the components of the $Lambda_c^ +$ polarization vector. The precession angle of the polarization in the process of baryon channeling in a bent crystal is directly related to these asymmetries. The decay rate and asymmetry parameter for the $Lambda_c^+to K^- , Delta (1232)^{++}$ decay are calculated in the pole model and compared with experiment.
We present a study on inclusive emissions of a double $Lambda_c$ or of a $Lambda_c$ plus a light-flavored jet system as probe channels in the semi-hard regime of QCD. Our formalism relies on the so-called hybrid high-energy/collinear factorization, w here the standard collinear description is supplemented by the $t$-channel resummation `a la BFKL of energy logarithms up to the next-to-leading accuracy. We make use of the JETHAD modular interface, suited to the analysis of different semi-hard reactions, employing the novel KKSS19 parameterization for the description of parton fragmentation into $Lambda_c$ baryons. We provide predictions for rapidity distributions and azimuthal correlations, that can be studied at current and forthcoming LHC configurations, hunting for possible stabilizing effects of the high-energy series.
A new approach to the analysis of three body decays is presented. Model-independent results are obtained for the swave $Kpi$ amplitude as a function of $Kpi$ invariant mass. These are compared with results from $Kmpip$ elastic scattering, and the pre diction of the Watson theorem, that the phase behavour be the same below $Keta^{prime}$ threshold, is tested. Contributions from $I=half$ and $I={3over 2}$ are not resolved in this study. If $I=half$ dominates, however, the Watson theorem does not describe these data well.}
The doubly charmed baryon decay $Xi_{cc}^{++} rightarrow Xi_{c}^{+} pi^{+}$ is observed for the first time, with a statistical significance of $5.9sigma$, confirming a recent observation of the baryon in the $Lambda_c^{+} K^{-} pi^{+} pi^{+}$ final s tate. The data sample used corresponds to an integrated luminosity of $1.7,mathrm{fb}^{-1}$, collected by the LHCb experiment in $pp$ collisions at a center-of-mass energy of $13mathrm{,Tekern -0.1em V}$. The $Xi_{cc}^{++}$ mass is measured to be begin{equation} onumber 3620.6pm 1.5~(text{stat})pm 0.4~(text{syst}) pm 0.3~(Xi_{c}^{+})~text{MeV}/it{c}^{2}, end{equation} and is consistent with the previous result. The ratio of branching fractions between the decay modes is measured to be begin{equation} onumber frac{mathcal{B} (Xi_{cc}^{++} rightarrow Xi_{c}^{+} pi^{+}) times mathcal{B}(Xi_{c}^{+} rightarrow pK^{-}pi^{+})} {mathcal{B} (Xi_{cc}^{++} rightarrow Lambda_c^{+} K^{-} pi^{+} pi^{+}) times mathcal{B}(Lambda_c^{+} rightarrow pK^{-}pi^{+})} = 0.035pm 0.009~(text{stat}) pm 0.003~(text{syst}). end{equation}
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