Dijet Acoplanarity in CUJET3 as a Probe of the Nonperturbative Color Structure of QCD Perfect Fluids

Journal Article · Thu Dec 10 00:00:00 EST 2020 · Nuclear Physics. A

DOI:https://doi.org/10.1016/j.nuclphysa.2020.121938· OSTI ID:1826321

Gyulassy, M. ^[1]; Jacobs, P. M. ^[2]; Liao, J. ^[3]; Shi, S. ^[4]; Wang, X. N. ^[1]; Yuan, F. ^[2]

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1. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Central China Normal Univ., Wuhan (China)
2. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
3. Indiana Univ., Bloomington, IN (United States)
4. McGill Univ., Montreal, QC (Canada)

Using the CUJET3=DGLV+VISHNU jet-medium interaction framework, we show that dijet azimuthal acoplanarity in high energy A + A collisions is sensitive to possible non-perturbative enhancement of the jet transport coefficient, $$\hat{q}$$(T,E), in the QCD crossover temperature T ~ 150–300 MeV range. With jet-medium couplings constrained by global RHIC& LHC χ² fits to nuclear modification data on R_AA(p_T > 20) GeV, we compare predictions of the medium induced dijet transverse momentum squared, $$Q_s^2~\langle \hat{q}L\rangle~ΔΦ^2E^2$$, in two models of the temperature, T, and jet energy E dependence of the jet medium transport coefficient, $$\hat{q}$$(T,E)). In one model, wQGP, the chromo degrees of freedom (dof) are approximated by a perturbative dielectric gas of quark and gluons dof. In the second model, sQGMP, we consider a nonperturbative partially confined semi-Quark-Gluon-Monopole-Plasma with emergent color magnetic dof constrained by lattice QCD data. Unlike the slow variation of the scaled jet transport coefficient, $$\hat{q}_{wQGP}/T^3$$, the sQGMP model $$\hat{q}_{sQGMP}/T^3$$ features a sharp maximum in the QCD confinement crossover T range. We show that the dijet path averaged medium induced azimuthal acoplanarity, Δφ², in sQGMP is robustly ~ 2 times larger than in perturbative wQGP. even though the radiative energy loss in both models is very similar as needed to fit the same R_AA data. Future A+A dijet acoplanarity measurements constrained together with single jet R_AA and ν_n measurements therefore appears to be a promising strategy to search for possible signatures of critical opalescence like phenomena in the QCD confinement temperature range.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: Natural Science and Engineering Research Council of Canada (NERSC); USDOE
• Grant/Contract Number: AC02-05CH11231
• OSTI ID: 1826321
• Alternate ID(s): OSTI ID: 1760956
• Journal Information: Nuclear Physics. A, Journal Name: Nuclear Physics. A Vol. 1005; ISSN 0375-9474
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
dijet acoplanarity
heavy ion collisions
jet quenching
quark gluon plasmas