Correlated pion-proton pair emission off hot and dense QCD matter

0544737 - ÚJF 2022 RIV NL eng J - Článek v odborném periodiku
Adamczewski-Musch, J. - Arnold, O. - Behnke, C. - Belounnas, A. - Belyaev, A. - Berger-Chen, J. C. - Blanco, A. - Blume, C. - Chlad, Lukáš - Kugler, Andrej - Rodriguez Ramos, Pablo - Sobolev, Yuri, G. - Svoboda, Ondřej - Tlustý, Pavel - Wagner, Vladimír … celkem 122 autorů
Correlated pion-proton pair emission off hot and dense QCD matter.
Physics Letters. B. Roč. 819, AUG (2021), č. článku 136421. ISSN 0370-2693. E-ISSN 1873-2445
Grant CEP: GA MŠMT EF18_046/0016066; GA MŠMT LTT17003
Výzkumná infrastruktura: FAIR-CZ II - 90112
Institucionální podpora: RVO:61389005
Klíčová slova: HADES * Baryonic resonances * heavy-ion reactions
Obor OECD: Particles and field physics
Impakt faktor: 4.950, rok: 2021
Způsob publikování: Open access
https://doi.org/10.1016/j.physletb.2021.136421

In this letter we report the first multi-differential measurement of correlated pion-proton pairs from 2 billion Au+Au collisions at root(S)(NN) = 2.42 GeV collected with HADES. In this energy regime the population of Delta(1232) resonances plays an important role in the way energy is distributed between intrinsic excitation energy and kinetic energy of the hadrons in the fireball. The triple differential d(3)N/dM(pi +/- p)dp(T)dy distributions of correlated pi(+/-)p pairs have been determined by subtracting the pi p combinatorial background using an iterative method. The invariant-mass distributions in the Delta(1232) mass region show strong deviations from a Breit-Wigner function with vacuum width and mass. The yield of correlated pion-proton pairs exhibits a complex isospin, rapidity and transverse-momentum dependence. In the invariant mass range 1.1 < M-inv(GeV/c(2)) < 1.4, the yield is found to be similar for pi(+)p and pi(-)p pairs, and to follow a power law (A(part))(alpha), where (A(part)) is the mean number of participating nucleons. The exponent alpha depends strongly on the pair transverse momentum (p(T)) while its p(T)-integrated and charge-averaged value is alpha = 1.5 +/- 0.08(st) +/- 0.2(sy).
Trvalý link: http://hdl.handle.net/11104/0321560