Towards resolving the Λ3H lifetime puzzle

Recent Λ3H lifetime measurements in relativistic heavy ion collision experiments have yielded values shorter by (30±8)% than the free Λ lifetime τΛ, thereby questioning the naive expectation τ(HΛ3)≈τΛ for a weakly bound Λ hyperon. Here we apply the closure approximation introduced by Dalitz and cowo...

Full description

Bibliographic Details
Main Authors: A. Gal, H. Garcilazo
Format: Article
Language:English
Published: Elsevier 2019-04-01
Series:Physics Letters B
Online Access:http://www.sciencedirect.com/science/article/pii/S037026931930108X
Description
Summary:Recent Λ3H lifetime measurements in relativistic heavy ion collision experiments have yielded values shorter by (30±8)% than the free Λ lifetime τΛ, thereby questioning the naive expectation τ(HΛ3)≈τΛ for a weakly bound Λ hyperon. Here we apply the closure approximation introduced by Dalitz and coworkers to evaluate the Λ3H lifetime, using Λ3H wavefunctions generated by solving three-body Faddeev equations. Our result, disregarding pion final-state interaction (FSI), is τ(HΛ3)=(0.90±0.01)τΛ. In contrast to previous works, pion FSI is found attractive, reducing further τ(HΛ3) to τ(HΛ3)=(0.81±0.02)τΛ. We also evaluate for the first time τ(nΛ3), finding it considerably longer than τΛ, contrary to the shorter lifetime values suggested by the GSI HypHI experiment for this controversial hypernucleus. Keywords: Light Λ hypernuclei, Hypertriton lifetime, Faddeev calculations
ISSN:0370-2693