A1 Journal article (refereed)
Study of the Λ–Λ interaction with femtoscopy correlations in pp and p–Pb collisions at the LHC (2019)

ALICE Collaboration. (2019). Study of the Λ–Λ interaction with femtoscopy correlations in pp and p–Pb collisions at the LHC. Physics Letters B, 797, Article 134822. https://doi.org/10.1016/j.physletb.2019.134822

JYU authors or editors

Publication details

All authors or editors: ALICE Collaboration

Journal or series: Physics Letters B

ISSN: 0370-2693

eISSN: 1873-2445

Publication year: 2019

Volume: 797

Article number: 134822

Publisher: Elsevier

Publication country: Netherlands

Publication language: English

DOI: https://doi.org/10.1016/j.physletb.2019.134822

Publication open access: Openly available

Publication channel open access: Open Access channel

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/65431

Publication is parallel published: https://arxiv.org/abs/1905.07209

Abstract

This work presents new constraints on the existence and the binding energy of a possible Λ–Λ bound state, the H-dibaryon, derived from Λ–Λ femtoscopic measurements by the ALICE collaboration. The results are obtained from a new measurement using the femtoscopy technique in (Figure presented.) collisions at s=13 TeV and p–Pb collisions at sNN=5.02 TeV, combined with previously published results from (Figure presented.) collisions at s=7 TeV. The Λ–Λ scattering parameter space, spanned by the inverse scattering length f0 −1 and the effective range d0, is constrained by comparing the measured Λ–Λ correlation function with calculations obtained within the Lednický model. The data are compatible with hypernuclei results and lattice computations, both predicting a shallow attractive interaction, and permit to test different theoretical approaches describing the Λ–Λ interaction. The region in the (f0 −1,d0) plane which would accommodate a Λ–Λ bound state is substantially restricted compared to previous studies. The binding energy of the possible Λ–Λ bound state is estimated within an effective-range expansion approach and is found to be BΛΛ=3.2−2.4 +1.6(stat)−1.0 +1.8(syst) MeV.

Keywords: particle physics

Contributing organizations

Ministry reporting: Yes

Reporting Year: 2019

JUFO rating: 2