Mon·Oct 20, 2025Monday·October 20, 2025

1. 01*

   Cumulants of the multiplicity distributions of identified particles measured in heavy-ion collisions by HADES

   Marvin Nabroth (for the HADES Collaboration)🇩🇪

   The HADES experiment investigates the reaction products of heavy-ion collisions at a few GeV, providing access to QCD matter at high net-baryon densities. A particular focus is the reconstruction of higher-order cumulant ratios of proton and light nuclei multiplicity distributions, which are considered sensitive probes of criticality through their connection to event-by-event (E-by-E) net-baryon number fluctuations. In this contribution, we summarize the experimental setup and outline the analysis strategy. The fluctuations are reconstructed using a novel approach that circumvents E-by-E particle identification by treating it probabilistically. We present several approaches for efficiency correction and apply a data-driven event-mixing procedure to correct for centrality fluctuations. The fully corrected normalized factorial cumulants of proton and deuteron multiplicity distributions are then presented and compared to corresponding STAR data. Our measurements extend the trends observed by STAR toward lower energies for the ratios $C_2/C_1$ and $C_3/C_1$. Finally, we show the rapidity dependence of factorial cumulant ratios and confront the results with canonical ensemble baselines that incorporate correlated particle production via local attractive interactions.

   nucl-exEPJ Web Conf.(2026)·2 citations
2. 02*

   First non-zero measurement of a nuclear electric dipole moment

   Gary Prézeau🇧🇷

   This paper reports the first non-zero measurement of a nuclear electric dipole moment using a novel method based on the rate of change of a supercurrent first proposed in 2016~\cite{https://doi.org/10.48550/arxiv.1604.02152} and fleshed out in this current paper. The theory, experimental concept and implementation are described in detail. The non-zero nuclear electric dipole moment measured with over 1000 hours of data was that of ${}^{181}$Ta producing a best value $|d_{\text{e}}^{\text{Ta}}|=(3.39\pm 0.31_{\text{stat}})\cdot 10^{-32}e\cdot \text{cm}$ and $|d_{\text{e}}^{\text{Ta}}|=(3.39\pm 3.18)\cdot 10^{-32}e\cdot \text{cm}>0$ at 99.985\%CL. There is an uncertainty on the value of overall multiplicative parameters such as the self-inductance of the superconducting circuit ($\pm 4\%$), the mutual inductance between the SQUID pickup coil and the sample wire ($\pm 15\%$), and the magnitude of the solenoid current ($\pm 5\%$). An upper-limit was estimated for the control element, ${}^{207}$Pb, $|d_{\text{e}}^{\text{Pb}}|\lesssim 1.2\cdot 10^{-31}e\cdot \text{cm}$ at 95\%CL.

   nucl-excond-mat.supr-conhep-phnucl-th+10 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.