Fri·Aug 22, 2025Friday·August 22, 2025

1. 01*

   Probing jet hadrochemistry in Pb--Pb collisions with ALICE

   Sierra Cantway (for the ALICE Collaboration)🇺🇸

   Jet substructure measurements in heavy-ion collisions provide constraints on jet quenching and the medium response in the QGP. Though there has been remarkable progress in inclusive-charged-hadron jet substructure measurements, understanding the identified particle composition of jets and their modification in heavy-ion collisions has proven challenging. Jet quenching models predict that the jet hadrochemical composition may be modified in heavy-ion collisions due to jet-medium interactions, as well as the medium response. Measurements of identified particles in jets can help discriminate between various parton-QGP interactions. We present the first measurements of $\pi$, K, and p ratios within charged-particle-jets, as well as in the underlying event, as a function of particle transverse momentum in pp and Pb--Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV. These measurements leverage the excellent PID capabilities of ALICE over a wide transverse momentum range. These results aim to understand soft particle production mechanisms and distinguish modified jet fragmentation from bulk effects.

   nucl-exEPJ Web Conf.(2025)·1 citation
2. 02*

   News on strangeness production from the NA61/SHINE experiment

   Yuliia Balkova🇵🇱 · Tatjana Šuša🇭🇷

   Strangeness production in high-energy hadronic and nuclear collisions continues to be one of the central topics in the study of strongly interacting matter. The data collected by the NA61/SHINE experiment at the CERN SPS North Area allow for a comprehensive scan of the strangeness production across various collision energies and system sizes. This article focuses on the new results of the strangeness production in central collisions of medium-sized nuclei, such as Ar+Sc, at the SPS energy range. In particular, the results for Lambda hyperons and charged and neutral $K$ mesons are shown. The energy and system size dependencies of Lambda-to-pion and strangeness-to-pion ratios are also explored. Moreover, an unexpected excess of charged over neutral $K$ meson production in Ar+Sc and ${\pi }^{-}$+C interactions is presented. The obtained results are compared with predictions from selected particle production models, as well as with existing world data from proton-proton and nucleus-nucleus collisions.

   nucl-exhep-exEPJ Web Conf.(2026)·5 citations
3. 03*

   Direct Neutron Reactions in Storage Rings Utilizing a Supercompact Cyclotron Neutron Target

   Ariel Tarifeño-Saldivia🇪🇸 · César Domingo-Pardo🇪🇸 · Iris Dillmann🇨🇦 · Yuri A. Litvinov🇩🇪

   We propose a new approach for a high-density free-neutron target, primarily aimed at nuclear astrophysics reaction studies in inverse kinematics with radioactive ions circulating in a storage ring. The target concept integrates four key subsystems: a neutron production source driven by a supercompact cyclotron utilizing ${}^9$Be($p,xn$) reactions, an optimized moderator/reflector assembly using either heavy water or beryllium oxide with a graphite reflector shell to thermalize fast neutrons, a cryogenic liquid hydrogen moderator to maximize thermal neutron density in the interaction region, and beam pipe geometries that enable neutron-ion interactions while maintaining vacuum conditions for ion circulation. This integrated approach focuses on the feasibility by incorporating readily available technologies. Using a commercial supercompact cyclotron delivering a proton beam of 130 $\mu$A, the design achieves thermal neutron areal densities of $\sim 3.4\times 10^6$\,n/cm${}^2$ for a proof-of-concept demonstrator at the CRYRING ion-storage ring at GSI Darmstadt. This autonomous accelerator-target assembly design enables deployment at both, in-flight and ISOL facilities, to exploit their complementary production mechanisms. Potential upgrades based on higher-energy and/or higher-current cyclotrons will enable an increase in areal density to $\sim$10${}^9$ n/cm${}^2$. In combination with a customized low-energy storage ring and a radioactive ion-beam facility, the proposed solution could deliver luminosities above 10${}^{23}$ cm${}^{-2}$ s${}^{-1}$, thereby enabling neutron capture measurements of $\sim$mb cross sections within a few days of experiment. The proposed system represents a significant milestone towards enabling large neutron-capture surveys on short-lived nuclei, thereby opening a new avenue for understanding the synthesis of heavy elements in our universe. Accepted in PRAB.

   nucl-exphysics.ins-detPhys.Rev.Accel.Beams(2026)·1 citation
4. 04*

   High-precision determination of radiative corrections to superallowed nuclear beta decays

   Chien-Yeah Seng🇺🇸

   Superallowed $0^{+}\to 0^{+}$ transitions between $T=1$ nuclei have been a perfect avenue avenue for determining the Cabibbo-Kobayashi-Maskawa matrix element $V_{ud}$, which imposes powerful constraints on physics beyond the Standard Model at low energies. For a long time, the precision of $V_{ud}$ has been limited by uncertainties in radiative corrections that arise from non-perturbative strong interaction physics at both the hadronic and nuclear levels. In this talk, I will describe some recent efforts to pin down these corrections by combining dispersive analysis with experimental data, lattice QCD, and nuclear many-body calculations.

   ↳ nucl-thhep-exhep-lathep-ph+1EPJ Web Conf.(2025)·2 citations
5. 05*

   Modeling of Light Production in Inorganic Scintillators

   B. Kreider · I. Cox🇺🇸 · R. Grzywacz🇺🇸 · J. M. Allmond🇺🇸 · A. Augustyn · N. Braukman · P. Brionnet🇫🇷 · A. Esmaylzadeh🇩🇪 · J. Fischer🇩🇪 · N. Fukuda🇯🇵 · G. Garcia De Lorenzo · S. Go🇺🇸 and 16 other authors

   In recent experiments, inorganic scintillators have been used to study the decays of exotic nuclei, providing an alternative to silicon detectors and enabling measurements that were previously impossible. However, proper use of these materials requires us to understand and quantify the scintillation process. In this work, we propose a framework based on that of Birks [Proc. Phys. Soc. A 64, 874] and Meyer and Murray [Phys. Rev. 128, 98] to model the light output of inorganic scintillators in response to beams of energetic heavy ions over a broad range of energies. Our model suggests that, for sufficiently heavy ions at high energies, the majority of the light output is associated with the creation of delta electrons, which are induced by the passage of the beam through the material. These delta electrons dramatically impact the response of detection systems when subject to ions with velocities typical of beams in modern fragmentation facilities. We test the accuracy of our model with data from Lutetium Yttrium Orthosilicate (LYSO:Ce), a common inorganic scintillator. We compare calculated light production and quenching factors with experimental data for heavy ions of varying mass and energy as well as make a quantitative estimate of the effects of delta rays on overall light output. The model presented herein will serve as a basic framework for further studies of scintillator response to heavy ions. Our results are crucial in planning future experiments where relativistic exotic nuclei are interacting with scintillator detectors.

   ↳ physics.ins-detnucl-ex1 citation
6. 06*

   Proton Pressure: A Simplified Model

   Julliana Marinho Paszko🇧🇷 · Mauro Rogério Cosentino🇧🇷

   In this work, the authors present a simplified method for determining proton pressure, based on concepts from statistical mechanics, quantum chromodynamics - specifically asymptotic freedom of quarks - and other well-established physical concepts. The result obtained for the proton pressure was $0.3570\times 10^{35}$ Pa, which is consistent with recently reported experimental data.

   ↳ hep-phnucl-ex0 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.