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arXiv · 2508.17227

Effects of Geometric configuration in relativistic isobaric collisions at $\sqrt{s_{NN}}=200$ GeV

Akash Das·Satya Ranjan Nayak·B. K. Singh
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Abstract

In this work, we present a study on the effects of nuclear deformation ($\beta_2$,$\beta_3$) and surface diffuseness ($a$) on the charged hadron multiplicity ($N_{\mathrm{ch}}$) and elliptic flow ($v_2$), obtained in symmetric isobaric collisions of ${}^{96}_{44}\mathrm{Ru} + {}^{96}_{44}\mathrm{Ru}$ and ${}^{96}_{40}\mathrm{Zr} + {}^{96}_{40}\mathrm{Zr}$. The two extreme configurations (tip-tip and body-body) were used to determine the correlation between the final state observables and initial geometry using the HYDJET++ model. The octupole deformation parameter ($\beta_3$) enhances $N_{\mathrm{ch}}$ in central tip-tip Zr+Zr collisions and suppresses it in peripheral ones. In mid-central to peripheral body-body Zr+Zr collisions, $\beta_3$ leads to a reduction in charged hadron production. Surface-diffuseness ($a$), along with quadrapole deformation ($\beta_2$), also shows a significant impact on multiplicity and elliptic flow. The octupole deformation enhances elliptic flow in Zr's body-body collisions. Results are compared with the STAR blind-analysis data where available.

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Akash Das, Satya Ranjan Nayak, B. K. Singh. 2025-08-24. Effects of Geometric configuration in relativistic isobaric collisions at $\sqrt{s_{NN}}=200$ GeV. https://arxiv.org/abs/2508.17227

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