Annihilation dynamics plays a fundamental role in the baryon-antibaryon interaction (B-(B) over bar) at low-energy and its strength and range are crucial in the assessment of possible baryonic bound states. Experimental data on annihilation cross sections are available for the p-(p) over bar system but not in the low relative momentum region. Data regarding the B-(B) over bar interaction with strange degrees of freedom are extremely scarce, hence the modeling of the annihilation contributions is mainly based on nucleon-antinucleon (N-(N) over bar) results, when available. In this letter we present a measurement of the p-(p) over bar, p-(Lambda) over bar circle plus(p) over bar-Lambda and Lambda-(Lambda) over bar interaction using correlation functions in the relative momentum space in high-multiplicity triggered pp collisions at root s = 13 TeV recorded by ALICE at the LHC. In the p-(p) over bar system the couplings to the mesonic channels in different partial waves are extracted by adopting a coupled-channel approach with recent chi EFT potentials. The inclusion of these inelastic channels provides good agreement with the data, showing a significant presence of the annihilation term down to zero momentum. Predictions obtained using the Lednicky-Lyuboshits formula and scattering parameters obtained from heavy-ion collisions, hence mainly sensitive to elastic processes, are compared with the experimental p-(Lambda) over bar circle plus(p) over bar-Lambda and Lambda-(Lambda) over bar correlations. The model describes the Lambda-(Lambda) over bar data and underestimates the p-(Lambda) over bar circle plus(p) over bar-Lambda data in the region of momenta below 200 MeV/c. The observed deviation indicates a different contribution of annihilation channels to the two systems containing strange hadrons. (C) 2022 European Organization for Nuclear Research. Published by Elsevier B.V.
Investigating the role of strangeness in baryon???antibaryon annihilation at the LHC
D. ColellaMembro del Collaboration Group
;D. Di BariMembro del Collaboration Group
;M. Mazzilli;A. PalascianoMembro del Collaboration Group
;G. VolpeMembro del Collaboration Group
;
2022-01-01
Abstract
Annihilation dynamics plays a fundamental role in the baryon-antibaryon interaction (B-(B) over bar) at low-energy and its strength and range are crucial in the assessment of possible baryonic bound states. Experimental data on annihilation cross sections are available for the p-(p) over bar system but not in the low relative momentum region. Data regarding the B-(B) over bar interaction with strange degrees of freedom are extremely scarce, hence the modeling of the annihilation contributions is mainly based on nucleon-antinucleon (N-(N) over bar) results, when available. In this letter we present a measurement of the p-(p) over bar, p-(Lambda) over bar circle plus(p) over bar-Lambda and Lambda-(Lambda) over bar interaction using correlation functions in the relative momentum space in high-multiplicity triggered pp collisions at root s = 13 TeV recorded by ALICE at the LHC. In the p-(p) over bar system the couplings to the mesonic channels in different partial waves are extracted by adopting a coupled-channel approach with recent chi EFT potentials. The inclusion of these inelastic channels provides good agreement with the data, showing a significant presence of the annihilation term down to zero momentum. Predictions obtained using the Lednicky-Lyuboshits formula and scattering parameters obtained from heavy-ion collisions, hence mainly sensitive to elastic processes, are compared with the experimental p-(Lambda) over bar circle plus(p) over bar-Lambda and Lambda-(Lambda) over bar correlations. The model describes the Lambda-(Lambda) over bar data and underestimates the p-(Lambda) over bar circle plus(p) over bar-Lambda data in the region of momenta below 200 MeV/c. The observed deviation indicates a different contribution of annihilation channels to the two systems containing strange hadrons. (C) 2022 European Organization for Nuclear Research. Published by Elsevier B.V.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.