اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدSearch for doubly charmed baryons and study of charmed strange baryons at Belle
183
0
0.0
(
0
)
اسأل ChatGPT حول البحث
ﻻ يوجد ملخص باللغة العربية
We report results of a study of doubly charmed baryons and charmed strange baryons. The analysis is performed using a 980 fb^-1 data sample collected with the Belle detector at the KEKB asymmetric-energy e^+e^- collider. We search for doubly charmed baryons Xi_cc^+(+) with the Lambda_c^+K^-pi^+(pi^+) and Xi_c^0pi^+(pi^+) final states. No significant signal is observed. We also search for two excited charmed strange baryons, Xi_c(3055)^+ and Xi_c(3123)^+ with the Sigma_c^++(2455)K^- and Sigma_c^++(2520)K^- final states. The Xi_c(3055)^+ signal is observed with a significance of 6.6 standard deviations including systematic uncertainty, while no signature of the Xi_c(3123)^+ is seen. We also study properties of the Xi_c(2645)^+ and measure a width of 2.6 +- 0.2 (stat) +- 0.4 (syst) MeV/c^2, which is the first significant determination.
قيم البحث
اقرأ أيضاً
We present the energy spectra of the low lying doubly-charmed baryons using lattice quantum chromodynamics. We precisely predict the ground state mass of the charmed-strange Omega(cc) (1/2+) baryon to be 3712(11)(12) MeV which could well be the next
doubly-charmed baryon to be discovered at the LHCb experiment at CERN. We also predict masses of other doubly-charmed strange baryons with quantum numbers 3/2+, 1/2-, and 3/2-.
In this work, we evaluate the lifetimes of the doubly charmed baryons $Xi_{cc}^{+}$, $Xi_{cc}^{++}$ and $Omega_{cc}^{+}$. We carefully calculate the non-spectator contributions at the quark level where the Cabibbo-suppressed diagrams are also include
d. The hadronic matrix elements are evaluated in the simple non-relativistic harmonic oscillator model. Our numerical results are generally consistent with that obtained by other authors who used the diquark model. However, all the theoretical predictions on the lifetimes are one order larger than the upper limit set by the recent SELEX measurement. This discrepancy would be clarified by the future experiment, if more accurate experiment still confirms the value of the SELEX collaboration, there must be some unknown mechanism to be explored.
We report the discovery of $Xi_{c}(3055)^{0}$, observed by its decay into the final state $Lambda D^{0}$, and present the first observation and evidence of the decays of $Xi_c(3055)^{+}$ and $Xi_c(3080)^{+}$ into $Lambda D^{+}$. We also perform a com
bined analysis of the $Lambda D^{+}$ with the $Sigma_{c}^{++}K^{-}$ and $Sigma_{c}^{ast ++}K^{-}$ decay modes to measure the ratios of branching fractions, masses and widths with improved accuracy. We measure the ratios of branching fractions ${cal B}(Xi_{c}(3055)^{+} to Lambda D^{+})/{cal B}(Xi_{c}(3055)^{+} to Sigma_{c}^{++}K^{-})=5.09pm1.01pm0.76$, ${cal B}(Xi_{c}(3080)^{+} to Lambda D^{+})/{cal B}(Xi_{c}(3080)^{+} to Sigma_{c}^{++}K^{-})=1.29pm0.30pm0.15$, and ${cal B}(Xi_{c}(3080)^{+} to Sigma_{c}^{ast ++}K^{-})/{cal B}(Xi_{c}(3080)^{+} to Sigma_{c}^{++}K^{-})=1.07pm0.27pm0.01$, where the uncertainties are statistical and systematic. The analysis is performed using a 980 fb$^{-1}$ data sample collected with the Belle detector at the KEKB asymmetric-energy $e^{+}e^{-}$ collider.
We report a search for the doubly charmed baryon $Xi_{cc}^{+}$ through the decay $Xi_{cc}^{+} to Lambda_{c}^{+} K^{-} pi^{+}$, using a data sample corresponding to an integrated luminosity of $0.65~mathrm{pb^{-1}}$ of $pp$ collisions at $mathrm{sqrt{
s}} = 7~mathrm{TeV}$. In the mass range 3300-3800$~mathrm{MeV}/c^{2}$ no significant signal is observed. Upper limits at $95%$ confidence level are set on $R$, the ratio of the production cross section of the $Xi_{cc}^{+}$ times the relevant branching fraction over the $Lambda_{c}^{+}$ cross section, as a function of the $Xi_{cc}^{+}$ mass and lifetime. The largest upper limits on $R$ over the investigated mass range are $R<1.5times10^{-2}$ for a lifetime of $100~mathrm{fs}$ and $R<3.9times10^{-4}$ for a lifetime of $400~mathrm{fs}$.
The vast amount of $coverline{c}$ production that can be recorded by the LHCb detector makes it an ideal environment to study the hadronic production of charmed baryons, along with the properties of their decays. We briefly describe the LHCb experime
nt and the triggering mechanisms it uses for recording charm production. Previous charmed baryon results from LHCb are detailed, with a description of the future plans for the charmed baryon programme.
سجل دخول لتتمكن من نشر تعليقات
التعليقات
جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
