Exploring the $Λ$-deuteron interaction via correlations in heavy-ion collisions

Abstract

Λ-deuteron two-particle momentum correlation functions, to be measured in high-energy heavyion collisions, are investigated. In particular, the question is addressed whether such correlations can serve as an additional and alternative source of information on the elementary ΛN interaction. The study is performed within the Lednicky-Lyuboshits formalism, utilizing an effective range expansion for the two relevant S-wave Λd amplitudes with parameters taken from the literature. It is found that in collisions characterized by a large emitting source the Λd correlation function is predominatly sensitive to the quartet state ( 4 S 3/2 ). In contrast, for small source sizes the contribution from the doublet partial wave ( 2 S 1/2 ) could be significant. Though the latter is constrained by the hypertriton binding energy, its present experimental uncertainty impedes an accurate determination of the doublet amplitude and, in turn, complicates conclusions on the quartet state.

Nature of the $Λnn$ $(J^π=1/2^+, I=1)$ and ${\rm ^3_ΛH^*} (J^π=3/2^+, I=0)$ states

“…As demonstrated in that work the virtual state 3 Λ H * pole position close to the Λ+d threshold strongly affects the Λd s-wave phase shifts in J π = 3/2 + channel. The calculated Λd scattering lengths and effective ranges from this work were further employed by Haidenbauer in the study of Λd correlation functions within the Lednicky-Lyuboshits formalism [18]. It is to be noted that the nature of the The / πEFT approach was applied to s-shell Λ hypernuclei and, among others, the experimental value of the Λ separation energy B Λ in 5 Λ He was successfully reproduced [20].…”