2019/05/31 by ALICE Collaboration, S. Acharya, D. Adamová +98 · 1 citation
Physics and Astronomy · #Bound state #Combinatorics #Energy (signal processing) #Geometry #High-Energy Particle Collisions Research #Inverse #Lambda #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum Chromodynamics and Particle Interactions #Quantum mechanics #hep-ex #nucl-ex
paper · pdf · doi:10.1016/j.physletb.2019.134822
published as Phys. Lett. B 797 (2019) 134822 · 21 pages, 4 captioned figures, 1 table, authors from page 16, published version, figures at http://alice-publications.web.cern.ch/node/5288
openalex publication_date 2019/08/01 · openalex created_date 2019/08/13 · arxiv created 2019/10/24 · arxiv updated 2019/10/25 · openalex updated_date 2026/08/05
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 pp collisions at √(s)=13 TeV and p-Pb collisions at √sNN=5.02 TeV, combined with previously published results from p-Pb 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 Lednicky 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+1.6-2.4(stat)+1.8-1.0(syst) MeV.