اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدAsymmetries of anti-triplet charmed baryon decays
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We analyze the decay processes of ${bf B}_c to {bf B}_n M$ with the $SU(3)_F$ flavor symmetry and spin-dependent amplitudes, where ${bf B}_c({bf B}_n)$ and $M$ are the anti-triplet charmed (octet) baryon and nonet meson states, respectively. In the $SU(3)_F$ approach, it is the first time that the decay rates and up-down asymmetries are fully and systematically studied without neglecting the ${cal O}(overline{15})$ contributions of the color anti-symmetric parts in the effective Hamiltonian. Our results of the up-down asymmetries based on $SU(3)_F$ are quite different from the previous theoretical values in the literature. In particular, we find that the up-down symmetry of $ alpha(Lambda_c^+to Xi^0 K^+)_{SU(3)} = 0.94^{+0.06}_{-0.11}$, which is consistent with the recent experimental data of $0.77pm0.78$ by the BESIII Collaboration, but predicted to be zero in the literature. We also examine the $K_S^0-K_L^0$ asymmetries between the decays of ${bf B}_c to {bf B}_n K_S^0$ and ${bf B}_c to {bf B}_n K_L^0$ with both Cabibbo-allowed and doubly Cabibbo-suppressed transitions.
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We systematically study the semileptonic decays of ${bf B_c} to {bf B_n}ell^+ u_{ell}$ in the light-front constituent quark model, where ${bf B_c}$ represent the anti-triplet charmed baryons of $(Xi_c^0,Xi_c^+,Lambda_c^+)$ and ${bf B_n}$ correspond
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We give a systematic study of ${bf B}_cto {bf B}_n V$ decays, where ${bf B}_c$ and $ {bf B}_n$ correspond to the anti-triplet charmed and octet baryons, respectively, while $V$ stand for the vector mesons. We calculate the color-symmetric contributio
ns to the decays from the effective Hamiltonian with the factorization approach and extract the anti-symmetric ones based on the experimental measurements and $SU(3)_F$ flavor symmetry. We find that most of the existing experimental data for ${bf B}_cto {bf B}_n V$ are consistent with our fitting results. We present all the branching ratios of the Cabbibo allowed, singly Cabbibo suppressed and doubly Cabbibo suppressed decays of ${bf B}_cto {bf B}_n V$. The decay parameters for the daughter baryons and mesons in ${bf B}_cto {bf B}_n V$ are also evaluated. In particular, we point out that the Cabbibo allowed decays of $Lambda_c^+ to Lambda^0 rho^+$ and $ Xi_c^0 to Xi^- rho^+$ as well as the singly Cabbibo suppressed ones of $Lambda_c^+ to Lambda^0 K^{*+}$, $Xi_c^+ to Sigma^+ phi$ and $Xi_c^0to Xi^- K^{*+}$ have large branching ratios and decay parameters with small uncertainties, which can be tested by the experimental searches at the charm facilities.
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e the experimental progress and the theoretical development since 2015.
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