Strong decays of charmed baryons in heavy hadron chiral perturbation theory: An update

We first give a brief overview of the charmed baryon spectroscopy and discuss their possible structure and spin-parity assignments in the quark model. With the new Belle measurement of the widths of Sigma(c)(2455) and Sigma(c)(2520) and the recent CDF measurement of the strong decays of Lambda(c)(2595) and Lambda(c)(2625), we give updated coupling constants in heavy hadron chiral perturbation theory. We find g(2) = 0.565(-0.024)(+0.011) for P-wave transitions between s-wave and s-wave baryons, and h(2), one of the couplings responsible for S-wave transitions between s-wave and p-wave baryons, is extracted from Lambda(c)(2595)(+) -> Lambda(+)(c)pi pi to be 0.63 +/- 0.07. It is substantially enhanced compared to the old value of order 0.437. With the help from the quark model, two of the couplings h(10) and h(11) responsible for D-wave transitions between s-wave and p-wave baryons are determined from Sigma(c)(2880) decays. There is a tension for the coupling h(2) as its value extracted from Lambda(c) (2595)(+) -> Lambda(+)(c) pi pi pp will imply Xi(c) (2790)(0) -> Xi(c)'pi and Xi(c)(2815)(+) -> Xi(*)(c)pi rates slightly above the current limits. It is conceivable that SU(3) flavor symmetry breaking can help account for the discrepancy.