The production of K*(892)(+/-) meson resonance is measured at midrapidity (|y| < 0.5) in Pb-Pb collisions at root s(NN) = 5.02 TeV using the ALICE detector at the CERN Large Hadron Collider. The resonance is reconstructed via its hadronic decay channel K *( 892)(+/-) -> K-S(0)pi(+/-). The transverse momentum distributions are obtained for various centrality intervals in the p(T) range of 0.4-16 GeV/c. Measurements of integrated yields, mean transverse momenta, and particle yield ratios are reported and found to be consistent with previous ALICE measurements for K *(892)(0) within uncertainties. The p(T)-integrated yield ratio 2 K*(892)(+/-)/(K+ + K-) in central Pb-Pb collisions shows a significant suppression at a level of 9.3 sigma relative to pp collisions. Thermal model calculations result in an overprediction of the particle yield ratio. Although both hadron resonance gas in partial chemical equilibrium (HRG-PCE) and MUSIC + SMASH simulations consider the hadronic phase, only HRG-PCE accurately represents the measurements, whereas MUSIC + SMASH simulations tend to overpredict the particle yield ratio. These observations, along with the kinetic freeze-out temperatures extracted from the yields measured for light-flavored hadrons using the HRG-PCE model, indicate a finite hadronic phase lifetime, which decreases with increasing collision centrality percentile. The p(T)-differential yield ratios 2 K*(892)(+/-)/(K+ + K-) and 2 K *(892)(+/-) /( pi(+) + pi(-)) are presented and compared with measurements in pp collisions at root s = 5.02 TeV. Both particle ratios are found to be suppressed by up to a factor of five at p(T) < 2.0 GeV/c in central Pb-Pb collisions and are qualitatively consistent with expectations for rescattering effects in the hadronic phase. The nuclear modification factor (R-AA) shows a smooth evolution with centrality and is found to be below unity at p(T) > 8 GeV/c, consistent with measurements for other light-flavored hadrons. The smallest values are observed in most central collisions, indicating larger energy loss of partons traversing the dense medium.

Acharya, S., Adamová, D., Aglieri Rinella, G., Agnello, M., Agrawal, N., Ahammed, Z., et al. (2024). K*(892)± resonance production in Pb-Pb collisions at sqrt(sNN)=5.02 TeV. PHYSICAL REVIEW C, 109(4), 1-18 [10.1103/physrevc.109.044902].

K*(892)± resonance production in Pb-Pb collisions at sqrt(sNN)=5.02 TeV

Agrawal, N.;Alici, A.;Arcelli, S.;Bellini, F.;Colocci, M.;Ercolessi, F.;Jacazio, N.;Malfattore, G.;Romanenko, G.;Rubini, N.;Scioli, G.;Strazzi, S.;
2024

Abstract

The production of K*(892)(+/-) meson resonance is measured at midrapidity (|y| < 0.5) in Pb-Pb collisions at root s(NN) = 5.02 TeV using the ALICE detector at the CERN Large Hadron Collider. The resonance is reconstructed via its hadronic decay channel K *( 892)(+/-) -> K-S(0)pi(+/-). The transverse momentum distributions are obtained for various centrality intervals in the p(T) range of 0.4-16 GeV/c. Measurements of integrated yields, mean transverse momenta, and particle yield ratios are reported and found to be consistent with previous ALICE measurements for K *(892)(0) within uncertainties. The p(T)-integrated yield ratio 2 K*(892)(+/-)/(K+ + K-) in central Pb-Pb collisions shows a significant suppression at a level of 9.3 sigma relative to pp collisions. Thermal model calculations result in an overprediction of the particle yield ratio. Although both hadron resonance gas in partial chemical equilibrium (HRG-PCE) and MUSIC + SMASH simulations consider the hadronic phase, only HRG-PCE accurately represents the measurements, whereas MUSIC + SMASH simulations tend to overpredict the particle yield ratio. These observations, along with the kinetic freeze-out temperatures extracted from the yields measured for light-flavored hadrons using the HRG-PCE model, indicate a finite hadronic phase lifetime, which decreases with increasing collision centrality percentile. The p(T)-differential yield ratios 2 K*(892)(+/-)/(K+ + K-) and 2 K *(892)(+/-) /( pi(+) + pi(-)) are presented and compared with measurements in pp collisions at root s = 5.02 TeV. Both particle ratios are found to be suppressed by up to a factor of five at p(T) < 2.0 GeV/c in central Pb-Pb collisions and are qualitatively consistent with expectations for rescattering effects in the hadronic phase. The nuclear modification factor (R-AA) shows a smooth evolution with centrality and is found to be below unity at p(T) > 8 GeV/c, consistent with measurements for other light-flavored hadrons. The smallest values are observed in most central collisions, indicating larger energy loss of partons traversing the dense medium.
2024
Acharya, S., Adamová, D., Aglieri Rinella, G., Agnello, M., Agrawal, N., Ahammed, Z., et al. (2024). K*(892)± resonance production in Pb-Pb collisions at sqrt(sNN)=5.02 TeV. PHYSICAL REVIEW C, 109(4), 1-18 [10.1103/physrevc.109.044902].
Acharya, S.; Adamová, D.; Aglieri Rinella, G.; Agnello, M.; Agrawal, N.; Ahammed, Z.; Ahmad, S.; Ahn, S. U.; Ahuja, I.; Akindinov, A.; Al-Turany, M.; ...espandi
File in questo prodotto:
Eventuali allegati, non sono esposti

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11585/995410
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 0
  • ???jsp.display-item.citation.isi??? 0
social impact