Cabibbo-allowed nonleptonic weak decays of charmed baryons

Abstract

(ii) nonfactorizable W -exchange effects are generally important; they can be comparable to and somtimes even dominate over factorizable contributions, depending on the decay modes under consideration, (iii) large-N c approximation for factorizable amplitudes also works in the heavy baryon sector and it accounts for the color nonsuppression of Λ + c → pK 0 relative to Λ + c → Λπ + , (iv) a measurement of the decay rate and the sign of the α asymmetry parameter of certain proposed decay modes will help discern various models; especially the sign of α in Λ + c → Σπ 1 decays can be used to unambiguously differentiate recent theoretical schemes from current algebra, and (v) p waves are the dominant contributions to the decays Λ + c → Ξ 0 K + and Ξ 0A c → Σ + K − , but they are subject to a large cancellation; this renders present theoretical predictions on these two channels unreliable. *

Heavy-flavor-conserving hadronic weak decays of heavy baryons

“…For the evaluation of the baryon matrix element of O − in the bag model, see [10,11]. The operator can be written as O − = 6(q 1 q 3 ) 1 (q 2 q 4 ) 2 , where the superscript i indicates that the quark operator acts only on the ith quark in the baryon wave function.…”

“…Hence, Ξ c → Λ c π can proceed through Wexchange which is a nonspectator effect. It is known that W -exchange plays a dramatic role in charmed baryon decays as it is not subject to helicity and color suppression [10,11].…”

“…The operator can be written as O − = 6(q 1 q 3 ) 1 (q 2 q 4 ) 2 , where the superscript i indicates that the quark operator acts only on the ith quark in the baryon wave function. In the bag model the parity-conserving matrix elements have the expression [10,11] …”

Charmed baryon weak decays with SU(3) flavor symmetry

“…To study the charmed baryon decays, since the most often used factorization approach in the b-hadron decays [18][19][20] has been demonstrated not to work for the twobody B c → B n M decays [21,22], where B n(c) and M are denoted as the (charmed) baryon and meson, respectively, one has to compute the sub-leading-order contributions or the final state interactions to take into account the non-factorizable effects [23][24][25][26][27], whereas the QCD-based models in the B c decays are not available yet. On the other hand, with the advantage of avoiding the detailed dynamics of QCD, the approach with SU(3) flavor (SU(3) f ) symmetry can relate decay modes in the b and c-hadron decays [22,[28][29][30][31][32][33][34][35][36][37], where the SU(3) amplitudes receive non-perturbative and non-factorizable effects, despite the unknown sources.…”

Antitriplet charmed baryon decays with SU(3) flavor symmetry

“…Since BESIII and LHCb are expected to search for all possible antitriplet charmed baryon decays, one can test whether or not the studies of Λ þ c → B n M can be applied to Ξ 0;þ c → B n M. Theoretically, the factorization for the b baryon decays [8][9][10][11][12][13] does not work for the charmed baryon decays, which receive corrections by taking into account the nonfactorizable effects [14][15][16][17][18][19]. On the other hand, the possible b or c hadron decay modes can be examined by the SUð3Þ f symmetry [20][21][22][23][24][25][26][27][28][29][30][31].…”