Wed·Apr 23, 2025Wednesday·April 23, 2025

1. 01*

   Antenna Arrays for CRES-based Neutrino Mass Measurement

   A. Ashtari Esfahani🇺🇸 · S. Bhagvati🇺🇸 · S. Böser🇩🇪 · M. J. Brandsema🇺🇸 · N. Buzinsky🇺🇸 · R. Cabral🇺🇸 · C. Claessens🇺🇸 · L. de Viveiros🇺🇸 · A. El Boustani🇪🇸 · M. G. Elliott🇺🇸 · M. Fertl🇩🇪 · J. A. Formaggio🇺🇸 and 56 other authors

   CRES is a technique for precision measurements of kinetic energies of charged particles, pioneered by the Project 8 experiment to measure the neutrino mass using the tritium endpoint method. It was recently employed for the first time to measure the molecular tritium spectrum and place a limit on the neutrino mass using a cm${}^3$-scale detector. Future direct neutrino mass experiments are developing the technique to overcome the systematic and statistical limitations of current detectors. This paper describes one such approach, namely the use of antenna arrays for CRES in free space. Phenomenology, detector design, simulation, and performance estimates are discussed, culminating with an example design with a projected sensitivity of $m_{\beta }<0.04\mathrm{eV}/c^2$. Prototype antenna array measurements are also shown for a demonstrator-scale setup as a benchmark for the simulation. By consolidating these results, this paper serves as a comprehensive reference for the development and performance of antenna arrays for CRES.

   ↳ physics.ins-detnucl-ex0 citations
2. 02*

   Angular structure of many-body correlations in atomic nuclei: From nuclear deformations to diffractive vector meson production in $\gamma A$ collisions

   Jean-Paul Blaizot🇫🇷 · Giuliano Giacalone🇨🇭

   There is growing evidence that high-energy scattering processes involving nuclei can offer unique insights into the many-body correlations present in nuclear ground states, in particular those of deformed nuclei. These processes involve, for instance, the collective anisotropic flows in heavy-ion collisions, or the diffractive production of vector mesons in photo-nuclear ($\gamma A$) interactions. In this paper, we use a classical approximation and simple analytical models in order to exhibit characteristic and universal features of ground-state correlation functions that result from the presence of a deformed intrinsic state. In the case of a small axial quadrupole deformation, we show that the random rotation of the intrinsic density of the nucleus leads to a specific quadrupole modulation of the lab-frame two-body density as a function of the relative azimuthal angle. As a phenomenological, albeit academic application, we analyze the diffractive production of vector mesons in high-energy $\gamma {+}^8$Be collisions. This demonstrates with the simplest deformed nucleus how the two-body correlations impact the $|t|$ dependence of the incoherent cross sections.

   ↳ nucl-thhep-exhep-phnucl-exEPJA(2025)·14 citations
3. 03*

   Electroweak form factors of baryons in dense nuclear matter

   G. Ramalho🇰🇷 · K. Tsushima🇧🇷 · Myung-Ki Cheoun🇰🇷

   There is evidence that the properties of hadrons are modified in a nuclear medium. Information about the medium modifications of the internal structure of hadrons is fundamental for the study of dense nuclear matter and high-energy processes, including heavy-ion and nucleus--nucleus collisions. At the moment, however, empirical information about medium modifications of hadrons is limited; therefore, theoretical studies are essential for progress in the field. In the present work, we review theoretical studies of the electromagnetic and axial form factors of octet baryons in symmetric nuclear matter. The calculations are based on a model that takes into account the degrees of freedom revealed in experimental studies of low and intermediate square transfer momentum $q^2=-Q^2$: valence quarks and meson cloud excitations of baryon cores. The formalism combines a covariant constituent quark model, developed for a free space (vacuum) with the quark--meson coupling model for extension to the nuclear medium. We conclude that the nuclear medium modifies the baryon properties differently according to the flavor content of the baryons and the medium density. The effects of the medium increase with density and are stronger (quenched or enhanced) for light baryons than for heavy baryons. In particular, the in-medium neutrino--nucleon and antineutrino--nucleon cross-sections are reduced compared to the values in free space. The proposed formalism can be extended to densities above the normal nuclear density and applied to neutrino--hyperon and antineutrino--hyperon scattering in dense nuclear matter.

   ↳ nucl-thhep-exhep-lathep-ph+1Symmetry(2025)·8 citations
4. 04*

   Compatibility of recent $\Xi$-nuclear bound state signals

   E. Friedman🇮🇱 · A. Gal🇮🇱

   J-PARC E05 reported recently a hint of a ${\Xi }^{-}-{}^{11}\mathrm{B}$ nuclear state in the ${}^{12}\mathrm{C}(K^{-},K^{+}){}_{\Xi }^{12}\mathrm{Be}$ spectrum, bound by $B_{{\Xi }^{-}}=8.9\pm 1.4{}_{-3.1}^{+3.8}$ MeV. Using a density-dependent $\Xi$-nuclear optical potential $V_{\mathrm{opt}}^{\Xi }(\rho )$ we explore to what extent a ${\Xi }_{1s}^{-}$ assignment of this nuclear state is compatible with ${\Xi }_{1s}^{-}$ and ${\Xi }_{1p}^{-}$ nuclear-state interpretations of ${\Xi }^{-}$ capture events in light emulsion-nuclei experiments. We find that the only acceptable ${\Xi }_{1s}^{-}$ assignment at present, barring an abnormally strong repulsive ${\rho }^2$ component of $V_{\mathrm{opt}}^{\Xi }(\rho )$, is that for the ${\Xi }^{-}-{}^{11}\mathrm{B}$ signal. This finding supports reassigning ${\Xi }^{-}$ capture events in ${}^{14}$N, originally assigned as ${\Xi }_{1s}^{-}-{}^{14}\mathrm{N}$ nuclear states, to ${\Xi }_{1p}^0-{}^{14}\mathrm{C}$ nuclear states. The depth of $V_{\mathrm{opt}}^{\Xi }(\rho )$ at nuclear-matter density ${\rho }_0=0.17$ fm${}^{-3}$ is then $-V_{\mathrm{opt}}^{\Xi }({\rho }_0)\sim 21$ MeV.

   ↳ nucl-thhep-phnucl-exPLB(2025)·7 citations
5. 05*

   Solid Target production for Astrophysical Reasearch: the European target laboratory partnership in ChETEC-INFRA

   Roberta Spartà🇮🇹 · Alexandra Spiridon🇷🇴 · Rosanna Depalo🇮🇹 · Denise Piatti🇮🇹 · Antonio Massara🇮🇹 · Nicoleta Florea🇷🇴 · Marcel Heine🇫🇷 · Radu-Florin Andrei🇷🇴 · Beyhan Bastin🇫🇷 · Ion Burducea🇷🇴 · Antonio Caciolli🇮🇹 · Matteo Campostrini🇮🇹 and 19 other authors

   The joint work of European target laboratories in the ChETEC-INFRA project is presented, to face the new experimental challenges of nuclear astrophysics. In particular, results are presented on innovative targets of 12,13C, 16O, and 19F that were produced, characterized, and, in some cases, tested under beam irradiation. STAR (Solid Targets for Astrophysics Research) is already acting to increase collaboration among laboratories, to achieve shared protocols for target production, and to offer a characterization service to the entire nuclear astrophysics community.

   ↳ physics.ins-detnucl-exEPJA(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.