Thu·Sep 5, 2024Thursday·September 5, 2024

1. 01*

   Deformation probes for light nuclei in their collisions at relativistic energies

   Hai-Cheng Wang🇨🇳 · Song-Jie Li🇨🇳 · Lu-Meng Liu🇨🇳 · Jun Xu🇨🇳 · Zhong-Zhou Ren🇨🇳

   We have investigated the performance of anisotropic flows $⟨v_n^2⟩$, transverse momentum fluctuations $⟨\delta p_T^2⟩$, and their correlations $⟨v_n^2\delta p_T⟩$ in central collisions at relativistic energies as probes of deformation parameters ${\beta }_n$ of colliding nuclei, if these nuclei are light nuclei with large ${\beta }_n$ and different configurations of $\alpha$ clusters. The effects from higher-order ${\beta }_n$ terms are illustrated by derived relations based on the overlap of two nuclei with uniform density distributions and by dynamic simulations of collisions of heavy nuclei whose density distributions are of a deformed Woods-Saxon (WS) form. While the linear relations between ${\beta }_n^2$, $⟨v_n^2⟩$, and $⟨\delta p_T^2⟩$ and that between ${\beta }_n^3$ and $⟨v_n^2\delta p_T⟩$ can be violated for extremely large ${\beta }_n$, they are mostly valid for realistic values of ${\beta }_n$, as long as the density distribution of colliding nuclei can be described by a deformed WS form. However, these linear relations are generally not valid with more realistic density distributions of light nuclei with $\alpha$ clusters, and the amount of deviation depends on the detailed $\alpha$-cluster configurations. Care must be taken when one tries to extract the deformation of light nuclei, and specific probes for $\alpha$-cluster structures in these nuclei are very much needed.

   ↳ nucl-thhep-exnucl-exPRC(2024)·14 citations
2. 02*

   Physics Perspectives with the ePIC Far-Forward and Far-Backward detectors

   Michael Pitt🇮🇱

   The forthcoming Electron--Ion Collider (EIC), which is expected to commence operations in the early 2030s, has already reached several significant milestones on its path toward completion. The core of the EIC physics program is the 3D imaging of partonic structures in protons and nuclei. The experimental detector setup required to enable this primary objective utilizes "far-forward" (FF) and "far-backward" (FB) detectors positioned downstream in the hadron-going and electron-going directions, respectively, from the interaction point of the EIC. The primary purpose of the FB detectors is to monitor luminosity and measure scattered electrons in collisions in the EIC, while the array of FF detectors is used to tag and reconstruct both charged and neutral particles that scatter at small angles. These detectors also enable a broader physics program than was initially envisioned, enhancing the EIC's research potential. The expanded capabilities have been a prime focus for engaging the broader nuclear physics community to build a robust groundwork for the EIC. In these proceedings, we will describe the FF/FB detectors and review the advanced forward physics program facilitated by them at the EIC.

   ↳ physics.ins-dethep-exnucl-exPoS(2025)·4 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.