Tue·Apr 22, 2025Tuesday·April 22, 2025

1. 01*

   Sensitivity of the CUPID experiment to $0\nu \beta \beta$ decay of ${}^{100}$Mo

   K. Alfonso · A. Armatol · C. Augier · F. T. Avignone III · O. Azzolini · A.S. Barabash · G. Bari · A. Barresi · D. Baudin · F. Bellini · G. Benato · L. Benussi and 180 other authors

   CUPID is a next-generation bolometric experiment to search for neutrinoless double-beta decay ($0\nu \beta \beta$) of ${}^{100}$Mo using Li${}_2$MoO${}_4$ scintillating crystals. It will operate 1596 crystals at $\sim$10 mK in the CUORE cryostat at the Laboratori Nazionali del Gran Sasso in Italy. Each crystal will be facing two Ge-based bolometric light detectors for $\alpha$ rejection. We compute the discovery and the exclusion sensitivity of CUPID to $0\nu \beta \beta$ in a Frequentist and a Bayesian framework. This computation is done numerically based on pseudo-experiments. For the CUPID baseline scenario, with a background and an energy resolution of $1.0\times 10^{-4}$ counts/keV/kg/yr and 5 keV FWHM at the Q-value, respectively, this results in a Bayesian exclusion sensitivity (90% c.i.) of ${\hat{T}}_{1/2}>1.6\times 10^{27}\mathrm{yr}$, corresponding to the effective Majorana neutrino mass of ${\hat{m}}_{\beta \beta }<9.6$ -- $28\mathrm{meV}$. The Frequentist discovery sensitivity (3$\sigma$) is ${\hat{T}}_{1/2}=1.0\times 10^{27}\mathrm{yr}$, corresponding to ${\hat{m}}_{\beta \beta }=12$ -- $36\mathrm{meV}$.

   nucl-exEPJC(2026)·7 citations
2. 02*

   Two-proton correlations in the decay of 48Ni and 45Fe

   A. Ortega Moral🇫🇷 · S.M. Wang🇨🇳 · J. Giovinazzo🇫🇷 · T. Roger🇫🇷 · B. Blank🇫🇷 · P. Ascher🇫🇷 · C. Borcea🇷🇴 · L. Caceres🇫🇷 · M. Caamano🇪🇸 · F. de Oliveira Santos🇫🇷 · A. de Roubin🇫🇮 · B. Fernandez-Dominguez🇪🇸 and 19 other authors

   The main observables of the rare two-proton emission process - half-life, total energy of the decay as well as energy and angular correlations between the emitted protons - have been measured for 48Ni and 45Fe in a recent experiment performed at the GANIL/LISE3 facility. The results, together with previous experimental work, are compared for the first time with calculations performed in the recently developed Gamow Coupled-Channel (GCC) framework and to 3-body predictions from literature. The comparison of the 48Ni and the 45Fe two-proton angular distributions with the GCC calculations confirms the adopted strength of the proton-proton interaction for both nuclei and the predominant small-angle emission. A comparison with 3-body model angular distributions indicates the shell closure of the f_7/2 orbital for 48Ni and a substantial occupancy of the p-orbital for 45Fe. Discrepancies between experimental data and theoretical predictions are found when studying the other observables: half-lives, total energy of the decay and energy correlations, showing the complexity of the description of the two-proton emission process.

   nucl-exPRC(2025)·1 citation
3. 03*

   An effective finite-range Gogny-type interaction for the quantum molecular dynamics like model

   Meiqi Sun🇨🇳 · Dandan Niu🇨🇳 · Junping Yang🇨🇳 · Ying Cui🇨🇳 · Zhuxia Li🇨🇳 · Qiang Zhao🇨🇳 · Kai Zhao🇨🇳 · Yingxun Zhang🇨🇳

   In this work, we propose an effective finite-range Gogny-type interaction that can be directly used in the quantum molecular dynamics (QMD) like model. Two methods for determining the parameters of the effective interaction are discussed. The first method establishes an approach to connect the conventional Gogny interaction in nuclear structure to that in heavy-ion collisions, the second method allows for the description of the symmetry energy varying from the supersoft to stiff, as well as the momentum-dependent symmetry potential, exhibiting behaviors ranging from monotonic to non-monotonic variations. This effective interaction opens up opportunities for a deeper understanding of finite-range interactions and non-monotonic momentum-dependent symmetry potentials in future studies.

   ↳ nucl-thnucl-ex0 citations
4. 04*

   The quest for the quark-gluon plasma from the perspective of dynamical models of relativistic heavy-ion collisions

   Marcus Bleicher🇩🇪 · Elena Bratkovskaya🇩🇪

   The physics of heavy-ion collisions is one of the most exciting and challenging directions of science for the last four decades. On the theoretical side one deals with a non-abelian field theory, while on the experimental side today's largest accelerators are needed to enable these studies. The discovery of a new stage of matter - called the quark-gluon plasma (QGP) - and the study of its properties is one of the major achievements of modern physics. In this contribution we briefly review the history of theoretical descriptions of heavy-ion collisions based on dynamical models, focusing on the personal experiences in this inspiring field.

   ↳ nucl-thhep-exhep-phnucl-ex0 citations
5. 05*

   Design of a Storage Ring based on a Fixed Field Alternating Gradient Configuration with an Internal Target for Heavy-Ion Beams with Stochastic Charge State Conversions

   Yoshihiro Ishi · Tomonori Uesugi · Yoshiharu Mori · Katsuhisa Nishio🇯🇵

   In the general use of a heavy-ion accelerator, an accelerated beam impinged on a target is spoiled into a beam dump. To make more efficient use of the beam, recycling of the beam passed through the target is proposed in the framework of the so-called energy recovery internal target (ERIT). In the ERIT system, the target is irradiated inside the circulating beam by recovering the energy lost in the target using rf cavities. So far, such a system has been realized only for proton beams. Here, the ERIT system for heavy-ion beam is demonstrated for the first time. A challenging issue is the circulation of all ions with different atomic charge. An ion has a probability of equilibrated charge state distribution after passing through the target, independent of the initial charge state. This phenomenon of stochastic charge state conversion (SCSC) causes rapid beam-emittance growth. To solve this problem, we developed a method to match the closed orbits and betatron functions of the beams in different charge states at the target location in a ring based on a scaling fixed field alternating gradient (FFA) lattice structure. We present the design of such an FFA ring and show, through full 6D beam tracking simulations, that transverse emittance growth can be effectively suppressed even in the presence of SCSC.

   ↳ physics.acc-phnucl-exPhys.Rev.Accel.Beams(2026)·1 citation
6. 06*

   Uncertainty minimization in electronic stopping cross-section measurements using the backscattering method

   Victor Pires · Arilson Silva🇺🇸 · Cleber L. Rodrigues · Nemitala Added · Manfredo H. Tabacniks · Tiago F. Silva · Flávio Matias · Helio Yoriyaz · Julian Shorto

   Accurate determination of electronic stopping cross sections is critical for ion beam analysis and related applications. While transmission methods are well established, backscattering approaches remain less explored from a metrological perspective, often lacking a systematic treatment of uncertainties. In this work, we present a quantitative framework to optimize experimental geometry in backscattering-based stopping measurements, explicitly accounting for both statistical and systematic errors. Applying the method to helium ions in gold thin films, we identify angular conditions that balance precision and accuracy, achieving total uncertainties below 3\% over a wide energy range. The results, benchmarked against SRIM and ICRU-49, demonstrate that our approach improves the reliability of RBS-derived stopping data and strengthens their use for reference purposes and model validation.

   ↳ physics.ins-detcond-mat.othernucl-exNucl.Instrum.Meth.B(2026)·0 citations
7. 07*

   Electronic stopping cross sections of tungsten to swift ions and comparisons with models

   Tiago F. Silva · Arilson Silva🇺🇸 · Cleber L. Rodrigues · Nemitala Added · Manfredo H. Tabacniks · Flávio Matias · Helio Yoriyaz · Julian Shorto

   Accurate stopping power data for tungsten is crucial for ion beam analysis (IBA) techniques applied to fusion-related materials. In this work, we present new experimental measurements of the stopping power of tungsten for protons and alpha particles, addressing key gaps in fundamental databases. Our results provide a densely spaced dataset, refining the practical uncertainty limits to approximately 1.5% for protons and 2.0% for alpha particles. We critically compare our findings with semi-empirical and theoretical models, evaluating their performance in describing the stopping power of tungsten for light projectiles. By improving the accuracy and reliability of stopping power data, we contribute to the enhancement of the applicability of ion-beam methods for characterizing tungsten in fusion-related research. These findings contribute to the refinement of semi-empirical models and support the ongoing efforts to develop more precise theoretical frameworks for ion-solid interactions in high-Z materials.

   ↳ cond-mat.othernucl-exNucl.Instrum.Meth.B(2025)·0 citations
8. 08*

   Imprints of octupole collectivity in uranium-238 on relativistic heavy-ion flow observables

   Chunjian Zhang🇨🇳 · Jiangyong Jia🇺🇸 · Jinhui Chen🇨🇳 · Chun Shen🇺🇸 · Lumeng Liu🇨🇳

   Some atomic nuclei exhibit enhanced octupole collectivity, reflected in finite reflection-asymmetric multipole correlations rather than necessarily in a rigid static pear-shaped ground state. Low-energy studies indicate finite octupole strength in uranium-238, commonly interpreted as soft or vibrational in nature, in addition to its large prolate quadrupole collectivity~\cite{MCGOWAN1994569,KIBEDI:2002wxc}, in addition to its large prolate quadrupole collectivity. Here we investigate how such octupole correlations can be encoded in the initial geometry of relativistic heavy-ion collisions and mapped to final-state flow observables. Using state-of-the-art hydrodynamic calculations, we demonstrate quantitative sensitivity to octupole-induced features encoded in the initial-state geometry and suggest a modest octupole collectivity in uranium-238, confirmed by the latest high-energy experimental measurements~\cite{STAR:2025elk}. These findings provide as a complementary probe of odd-order nuclear collectivity and help constrain quark-gluon plasma initial conditions.

   ↳ nucl-thnucl-exPRResearch(2026)·15 citations
9. 09*

   EXFOR utility codes (ForEXy) and their application to neutron fission cross section evaluation

   Naohiko Otuka · Vidya Devi · Osamu Iwamoto

   We developed a set of EXFOR utility codes (ForEXy) to process the information of the experimental nuclear reaction data stored in the EXFOR library. We designed a new JSON format (J4) for the EXFOR library, and developed a code converting the information in an EXFOR file to a J4 file (X4TOJ4) and another code converting it to an EXFOR file (J4TOX4) as a core part of this new code package. We also developed some other codes for managements of the EXFOR storage, bibliography and dictionary. As an application of the new code package, we constructed covariance matrices for the fast neutron induced fission cross sections of neptunium-237 in the EXFOR library by using the new codes, and applied them to evaluation of the cross section between 100 keV and 200 MeV.

   ↳ physics.comp-phnucl-exAppl.Radiat.Isot.(2025)·0 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.