Measurement of Λ4H and Λ4He binding energy in Au plus Au collisions at √sNN =3 GeV

作者：Aboona, B. E.; Adam, J.; Adamczyk, L.; Adams, J. R.; Adkins, J. K.; Aggarwal, I; Aggarwal, M. M.; Ahammed, Z.; Anderson, D. M.; Aschenauer, E. C.; Ashraf, M. U.; Atchison, J.; Bairathi, V; Baker, W.; Cap, J. G. Ball; Barish, K.; Behera, A.; Bellwied, R.; Bhagat, P.; Bhasin, A.; Bielcik, J.; Bielcikova, J.; Brandenburg, J. D.; Cai, X. Z.; Caines, H.; Sanchez, M. Calderon de la Barca; Cebra, D.; Chakaberia, I; Chaloupka, P.; Chan, B. K.; Chang, Z.; Chatterjee, A.; Chattopadhyay, S.; Chen, D.

来源：Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics , 2022, 834: 137449.

DOI：10.1016/j.physletb.2022.137449

• LIGHT HYPERNUCLEI

Measurements of mass and Lambda binding energy of H-4(Lambda) and He-4(Lambda) in Au+Au collisions at root s(NN) = 3 GeV are presented, with an aim to address the charge symmetry breaking (CSB) problem in hypernuclei systems with atomic number A = 4. The Lambda binding energies are measured to be 2.22 +/- 0.06(stat.)+/- 0.14(syst.) MeV and 2.38 +/- 0.13(stat.)+/- 0.12(syst.) MeV for H-4(Lambda) and He-4(Lambda), respectively. The measured Lambda binding-energy difference is 0.16 +/- 0.14(stat.) +/- 0.10(syst.) MeV for ground states. Combined with the gamma-ray transition energies, the binding-energy difference for excited states is -0.16 +/- 0.14(stat.) f 0.10(syst.) MeV, which is negative and comparable to the value of the ground states within uncertainties. These new measurements on the Lambda binding-energy difference in A = 4 hypernuclei systems are consistent with the theoretical calculations that result in Lambda B-Lambda(4) (1(ex)(c)(+)) approximate to -Delta B-Lambda(4) (0(g.s)(+)) < 0 and present a new method for the study of CSB effect using relativistic heavy-ion collisions.