Update on $J/\ensuremath{\psi}$ regeneration in a hadron gas

Open Access

Update on $J / ψ$ regeneration in a hadron gas

L. M. Abreu, K. P. Khemchandani, A. Martínez Torres, F. S. Navarra, and M. Nielsen

Phys. Rev. C 97, 044902 – Published 5 April 2018

Abstract

In heavy-ion collisions, after the quark-gluon plasma there is a hadronic gas phase. Using effective Lagrangians, we study the interactions of charmed mesons which lead to $J / ψ$ production and absorption in this gas. We update and extend previous calculations introducing strange meson interactions and also including the interactions mediated by the recently measured exotic charmonium resonances $Z (3900)$ and $Z (4025)$ . These resonances open new reaction channels for the $J / ψ$ , which could potentially lead to changes in its multiplicity. We compute the $J / ψ$ production cross section in processes such as $D_{(s)}^{(*)} + {\bar{D}}^{(*)} \to J / ψ + (π, ρ, K, K^{*})$ and also the $J / ψ$ absorption cross section in the corresponding inverse processes. Using the obtained cross sections as input to solve the appropriate rate equation, we conclude that the interactions in the hadron gas phase lead to a 20–24% reduction of the $J / ψ$ abundance. Within the uncertainties of the calculation, this reduction is the same at the Relativistic Heavy Ion Collider and the large Hadron Collider.

Received 25 December 2017
Revised 28 February 2018

DOI:https://doi.org/10.1103/PhysRevC.97.044902

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Funded by SCOAP³.

Published by the American Physical Society

Physics Subject Headings (PhySH)

Jets & heavy flavor physics Particle & resonance production Particle interactions Quark-gluon plasma Relativistic heavy-ion collisions Strong interaction

Nuclear Physics

Authors & Affiliations

L. M. Abreu^*

Instituto de Física, Universidade Federal da Bahia, Campus Universitário de Ondina, 40170-115, Bahia, Brazil

K. P. Khemchandani^†

Universidade Federal de São Paulo, 01302-907, São Paulo, Brazil

A. Martínez Torres^‡

Instituto de Física, Universidade de São Paulo, Rua do Matão 1371, 05508-090 São Paulo, São Paulo, Brazil

F. S. Navarra^§

Instituto de Física, Universidade de São Paulo, Rua do Matão 1371, 05508-090 São Paulo, São Paulo, Brazil and Institut de Physique Théorique, Université Paris Saclay, CEA, CNRS, F-91191, Gif-sur-Yvette, France

M. Nielsen^∥

Instituto de Física, Universidade de São Paulo, Rua do Matão 1371, 05508-090 São Paulo, São Paulo, Brazil and SLAC Nacional Acelerator Laboratory, Stanford University, Stanford, California 94309, USA

^*luciano.abreu@ufba.br
^†kanchan@if.usp.br
^‡amartine@if.usp.br
^§navarra@if.usp.br
^∥mnielsen@if.usp.br

Article Text

Click to Expand

References

Click to Expand

Issue

Vol. 97, Iss. 4 — April 2018

Reuse & Permissions

Author publication services for translation and copyediting assistance advertisement

Images

Figure 1
$J / ψ$ absorption cross sections in different processes as a function of the c.m. energy $\sqrt{s}$ . Top left panel: $π J / ψ$ in the initial state. Top right panel: $ρ J / ψ$ in the initial state. Solid, dashed, and dotted lines represent the $π (ρ) J / ψ \to D \bar{D}, π (ρ) J / ψ \to D^{*} \bar{D}$ , and $π (ρ) J / ψ \to D^{*} {\bar{D}}^{*}$ reactions, respectively. Bottom left panel: $K J / ψ$ in the initial state. Bottom right panel: $K^{*} J / ψ$ in the initial state. Solid, dashed, dotted, and dot-dashed lines represent the $K^{(*)} J / ψ \to D_{s} \bar{D}, K^{(*)} J / ψ \to D_{s}^{*} {\bar{D}}^{*}, K^{(*)} J / ψ \to D_{s}^{*} \bar{D}$ , and $K^{(*)} J / ψ \to D_{s} {\bar{D}}^{*}$ reactions, respectively.
Reuse & Permissions
Figure 2
$J / Ψ$ production cross sections in different processes as a function of the c.m. energy $\sqrt{s}$ . Top left panel: $π J / ψ$ in the final state. Top right panel: $ρ J / ψ$ in the final state. Solid, dashed, and dotted lines represent the $D \bar{D} \to π (ρ) J / ψ, D^{*} \bar{D} \to π (ρ) J / ψ$ , and $D^{*} {\bar{D}}^{*} \to π (ρ) J / ψ$ reactions, respectively. Bottom left panel: $K J / ψ$ in the final state. Bottom right panel: $K^{*} J / ψ$ in the final state. Solid, dashed, dotted, and dot-dashed lines represent the $D_{s} \bar{D} \to K^{(*)} J / ψ, D_{s}^{*} {\bar{D}}^{*} \to K^{(*)} J / ψ, D_{s}^{*} \bar{D} \to K^{(*)} J / ψ$ , and $D_{s} {\bar{D}}^{*} \to K^{(*)} J / ψ$ reactions, respectively.
Reuse & Permissions
Figure 3
$J / Ψ$ absorption (top left) and production (top right) cross sections by $π$ 's. The solid lines represent the cross sections obtained without including the $Z_{c}$ (3900) exchange in the $s$ channel. The dashed lines show the results with the exchange of $Z_{c}$ (3900) in the $s$ channel included. Bottom panels show the $J / Ψ$ absorption (bottom left) and production (bottom right) cross sections by $ρ$ 's. The solid lines in these panels show the cross sections obtained without including the $Z_{c}$ (4025) exchange in the $s$ channel. The dashed lines show the results obtained by including the $Z_{c}$ (4025) exchange in the $s$ channel.
Reuse & Permissions
Figure 4
$J / Ψ$ absorption and production cross sections by $π$ 's and $ρ$ 's as a function of the temperature. Top left panel: absorption reactions with $π J / Ψ$ in the initial state. $π J / Ψ \to D \bar{D}$ (solid line), $π J / Ψ \to D^{*} \bar{D}$ (dashed lines), and $π J / Ψ \to D^{*} {\bar{D}}^{*}$ (dotted lines). Top right panel: production reactions with $π J / Ψ$ in the final state. The line convention is the same as in the left panel. Bottom left panel: absorption reactions with $ρ J / Ψ$ in the initial state. $ρ J / Ψ \to D \bar{D}$ (solid line), $ρ J / Ψ \to D^{*} \bar{D}$ (dashed line), and $ρ J / Ψ \to D^{*} {\bar{D}}^{*}$ (dotted line) Bottom right panel: production reactions with $ρ J / Ψ$ in the final state. The line convention is the same as in the left panel.
Reuse & Permissions
Figure 5
$J / ψ$ absorption and production cross sections by $K$ 's and $K^{*}$ 's as a function of the temperature. Top left panel: absorption reactions with $K J / ψ$ in the initial state. $K J / ψ \to D_{s} \bar{D}$ (solid line), $K J / ψ \to D_{s}^{*} {\bar{D}}^{*}$ (dashed line), $K J / ψ \to D_{s}^{*} \bar{D}$ (dotted line), and $K J / ψ \to D_{s} {\bar{D}}^{*}$ (dot-dashed line). Top right panel: production reactions with $K J / ψ$ in the final state. The line convention is the same as in the left panel. Bottom left panel: absorption reactions with $K^{*} J / ψ$ in the initial state. $K^{*} J / ψ \to D_{s} \bar{D}$ (solid line), $K^{*} J / ψ \to D_{s}^{*} {\bar{D}}^{*}$ (dashed line), $K^{*} J / ψ \to D_{s}^{*} \bar{D}$ (dotted line), and $K^{*} J / ψ \to D_{s} {\bar{D}}^{*}$ (dot-dashed line). Bottom right panel: production reactions with $K^{*} J / ψ$ in the final state. The line convention is the same as in the left panel.
Reuse & Permissions
Figure 6
Left: Time evolution of $J / ψ$ abundance as a function of the proper time in central Au-Au collisions at $\sqrt{s_{N N}} = 200$ GeV. Solid, dashed, dotted, and dot-dashed lines represent the situations with only $π - J / ψ$ interactions and also adding the $ρ - J / ψ, K - J / ψ$ , and $K^{*} - J / ψ$ contributions, respectively. Right: the same as on the left for LHC conditions.
Reuse & Permissions

Physical Review C

covering nuclear physics

Update on $J / ψ$ regeneration in a hadron gas

L. M. Abreu, K. P. Khemchandani, A. Martínez Torres, F. S. Navarra, and M. Nielsen

Phys. Rev. C 97, 044902 – Published 5 April 2018

Abstract

Physics Subject Headings (PhySH)

Authors & Affiliations

Article Text

References

Issue

Physical Review C

covering nuclear physics

Update on J/ψ regeneration in a hadron gas

L. M. Abreu, K. P. Khemchandani, A. Martínez Torres, F. S. Navarra, and M. Nielsen

Phys. Rev. C 97, 044902 – Published 5 April 2018

Abstract

Physics Subject Headings (PhySH)

Authors & Affiliations

Article Text

References

Issue

Authorization Required

Other Options

Download & Share

Images

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Reuse & Permissions

Log In

Search

Article Lookup

Paste a citation or DOI

Enter a citation

Update on $J / ψ$ regeneration in a hadron gas