Strong and electromagnetic decays of two newΛc*baryons

Abstract

Two recently discovered excited charm baryons are studied within the framework of heavy hadron chiral perturbation theory. We interpret these new baryons which lie 308 MeV and 340 MeV above the A, as I = 0 members of a P-wave spin doublet. Differential and total decay rates for their double pion transitions down to the A, ground state are calculated. Estimates for their radiative decay rates are also discussed. We find that the experimentally determined characteristics of the A,' baryons may be simply understood within the effective theory.

Strong and electromagnetic decays ofp-wave heavy baryonsΛc1,Λc1Zhu1 2000Phys. Rev. D580372View full textAdd to dashboardCite

“…Due to the unknown coupling constant c RS in the chiral lagrangian for the heavy quark electromagnetic interactions, no numerical values are available [5]. However the decay width ratios of the four final states are exactly the same as ours if we ignore the isospin violations of the heavy multiplet masses in the heavy quark limit.…”

“…We take m c = 1. If we use naive dimensional analysis to let c RT [5] in TABLE III be of the order of unity or simply assume that the E1 transition coupling constant h p in (75) is of the same order of M1 transition one [9], we would get a width O(100) keV. Our result is in strong contrast with those from the bound state picture [7], where Γ(Λ c1 , Λ * c1 → Λ c γ) = 16, 21 keV and Γ(Λ b1 , Λ * b1 → Λ b γ) = 90, 119 keV.…”

“…In [5] the single pion and two pion strong decays and radiative decays of the Λ c1 doublet were discussed within the framework of heavy baryon chiral perturbation theory. Due to unknown couplings constants in the chiral Lagrangian, no actual decay widths were given.…”

Threshold effects in excited charmed baryon decays

“…[8], where their couplings to Goldstone bosons were first derived. These states can be grouped together into a superfield…”

Charmed Baryon Spectroscopy and Search for $CP$ Violation in $D^0 \to K_S^0\,\pi^+\,\pi^-$ at CDF

“…It includes two signals and several background components and is performed in a ∆M region from 290 to + decay width, the sum in the denominator corresponds to the total width. The two partial widths are derived in Reference [54] as combined with a random pion, and the sum of all three background contributions.…”