Decoding the flow evolution in Au+Au reactions at $1.23 A$ GeV using hadron flow correlations and dileptons

التفاصيل البيبلوغرافية
العنوان: Decoding the flow evolution in Au+Au reactions at $1.23 A$ GeV using hadron flow correlations and dileptons
المؤلفون: Reichert, Tom, Savchuk, Oleh, Kittiratpattana, Apiwit, Li, Pengcheng, Steinheimer, Jan, Gorenstein, Mark, Bleicher, Marcus
سنة النشر: 2023
المجموعة: Nuclear Experiment
Nuclear Theory
مصطلحات موضوعية: Nuclear Theory, Nuclear Experiment
الوصف: We investigate the development of the directed, $v_1$, and elliptic flow, $v_2$, in heavy ion collisions in mid-central Au+Au reactions at $E_\mathrm{lab}=1.23 A$ GeV. We demonstrate that the elliptic flow of hot and dense matter is initially positive ($v_2>0$) due to the early pressure gradient. This positive $v_2$ transfers its momentum to the spectators, which leads to the creation of the directed flow $v_1$. In turn, the spectator shadowing of the in-plane expansion leads to a preferred decoupling of hadrons in the out-of-plane direction and results in a negative $v_2$ for the observable final state hadrons. We propose a measurement of $v_1-v_2$ flow correlations and of the elliptic flow of dileptons as methods to pin down this evolution pattern. The elliptic flow of the dileptons allows then to determine the early-state EoS more precisely, because it avoids the strong modifications of the momentum distribution due to shadowing seen in the protons. This opens the unique opportunity for the HADES and CBM collaborations to measure the Equation-of-State directly at 2-3 times nuclear saturation density.
Comment: 8 pages, 5 figures
نوع الوثيقة: Working Paper
DOI: 10.1016/j.physletb.2023.137947
URL الوصول: http://arxiv.org/abs/2302.13919
رقم الأكسشن: edsarx.2302.13919
قاعدة البيانات: arXiv
الوصف
DOI:10.1016/j.physletb.2023.137947