The LHCb state PψsΛ(4338) as a triangle singularity
We present a model for the J/ψΛ spectrum in B−→J/ψΛp¯ decays, including the PψsΛ(4338) baryon recently observed by the LHCb collaboration. We assume production via triangle diagrams which couple to the final state via non-perturbative interactions which are constrained by heavy-quark and SU3-flavor...
Main Authors: | , |
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Format: | Article |
Language: | English |
Published: |
Elsevier
2023-03-01
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Series: | Physics Letters B |
Online Access: | http://www.sciencedirect.com/science/article/pii/S0370269323000497 |
Summary: | We present a model for the J/ψΛ spectrum in B−→J/ψΛp¯ decays, including the PψsΛ(4338) baryon recently observed by the LHCb collaboration. We assume production via triangle diagrams which couple to the final state via non-perturbative interactions which are constrained by heavy-quark and SU3-flavor symmetry. The bulk of the distribution is described by a triangle diagram with a color-favored electroweak vertex, while the sharp PψsΛ(4338) enhancement is due to the triangle singularity in another diagram featuring a 1/2− baryon consistent with Σc(2800). We predict a comparable PψsΛ(4338) signal in ηcΛ, and anticipate possible large isospin mixing effects through decays to J/ψΣ0 and ηcΣ0. |
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ISSN: | 0370-2693 |