Thu·May 29, 2025Thursday·May 29, 2025

1. 01*

   Improved direct measurement of low-energy resonances in the ${}^{21}$Ne(p,$\gamma$)${}^{22}$Na reaction

   R.S.Sidhu · F.Casaburo · E.Masha · M.Aliotta · C.Ananna · L.Barbieri · F.Barile · C.Baron · D.Bemmerer · A.Best · R.Biassisi · A.Boeltzig and 48 other authors

   In the nova temperature range, 0.1 GK $<T<$ 0.4 GK, several low-energy resonances dominate the ${}^{21}$Ne(p,$\gamma$)${}^{22}$Na reaction rate, which is currently affected by large uncertainties. We present a high-precision study of the resonances at $E_{\mathrm{r}}^{\mathrm{lab}}$ = 127.3, 271.4, 272.3, 291.5, and 352.6 keV, measured directly at the Laboratory for Underground Nuclear Astrophysics in Italy. The strengths of the 127.3, 271.4, and 291.5 keV resonances are consistent with previous measurements within 1$\sigma$. However, for the 272.3 keV and 352.6 keV resonances, we report strength values of (129.9 $\pm$ 5.8) meV and (14.9 $\pm$ 0.8) meV, respectively, more than a factor of 1.5 higher than literature values. In addition, we report on new branching ratios for the 127.3, 272.3, and 352.6 keV resonances, leading to updated decay schemes. Finally, we present a revised thermonuclear reaction rate and investigate its impact on the NeNa nucleosynthesis.

   nucl-exhep-exPRC(2025)·1 citation
2. 02*

   Convergence of the $ppp$ correlation function within the hyperspherical adiabatic basis

   E. Garrido🇪🇸 · A. Kievsky🇮🇹 · R. Del Grande🇮🇹 · L. Serksnyte🇨🇭 · M. Viviani🇮🇹 · L.E. Marcucci🇮🇹

   The computation of the three-particle correlation function involving three hadrons started just recently after the first publications of ALICE measurements. Key elements to be considered are the correct description of the asymptotics, antisymmetrization issues and, in most cases, the treatment of the Coulomb interaction. In the case of the $ppp$ correlation function, a first analysis was done where the hyperspherical adiabatic method was used to determine the $ppp$ wave function at different energies. Although the asymptotic behavior, antisymmetrization issues and the treatment of the Coulomb interaction were discussed in detail, the convergence properties of the adiabatic basis were studied at low energies around the formation of the correlation peak determined mainly by the $J^{\pi }=1/2^{-}$ and $3/2^{-}$ three-body states. Since many and very precise data have been taken or are planned to be measured at energies beyond the peak, we present an analysis of the convergence characteristics of the basis as the energy of the process increases. We show that in order to describe correctly the correlation tail it is necessary to consider three-body states up to $J^{\pi }=21/2^{-}$ whereas higher states can be considered as free. Once those states are incorporated solving the associate dynamical equations, the agreement with the experimental data is found to be excellent.

   ↳ nucl-thnucl-exPLB(2025)·5 citations
3. 03*

   Community input to the European Strategy on particle physics: Searches for Permanent Electric Dipole Moments

   M. Athanasakis-Kaklamanakis🇨🇭 · M. Au🇨🇭 · R. Berger🇩🇪 · S. Degenkolb🇩🇪 · J. De Vries🇳🇱 · S. Hoekstra🇳🇱 · A. Keshavarzi🇬🇧 · N. Neri🇮🇹 · D. Ries🇨🇭 · P. Schmidt-Wellenburg🇨🇭 · M. Tarbutt (Imperial College London, United Kingdom)🇬🇧

   Searches for electric dipole moments (EDMs) in fundamental particles and quantum systems with spin are pivotal experiments at the intersection of low-energy and high-precision particle physics. These investigations offer a complementary pathway to uncovering new physics beyond the Standard Model, parallel to high-energy collider searches. EDM experiments are among the most sensitive probes for detecting non-standard time-reversal (T) symmetry violations and, via the CPT theorem, CP-violation (CPV). Current EDM measurements test new physics at mass scales in or above the 10TeV to 100TeV range. This community input to the European Particle Physics Strategy Update highlights the status of the field, and describes challenges and opportunities in Europe.

   ↳ hep-exnucl-ex10 citations
4. 04*

   Probing the sensitivity of anisotropic flow coefficients to the initial nuclear structure in pO and OO collisions at the LHC

   Aswathy Menon Kavumpadikkal Radhakrishnan🇮🇳 · Suraj Prasad🇮🇳 · Neelkamal Mallick🇫🇮 · Raghunath Sahoo🇮🇳 · Gergely Gábor Barnaföldi🇭🇺

   RHIC and LHC have injected ${}^{16}\mathrm{O}$ nuclei in their accelerator complexes with a focus on investigating collectivity and the origin of quark-gluon plasma signatures in small collision systems. The ${}^{16}\mathrm{O}$ nuclei are known to possess clusters of $\alpha$-particles (${}^4\mathrm{He}$) inside the nucleus. This paper attempts to study the clustered-nuclear-geometry dependence of anisotropic flow coefficients such as elliptic flow ($v_2$) and triangular flow ($v_3$), which are sensitive to the nuclear geometry of colliding nuclei. The study is performed in pO and OO collisions at $\sqrt{s_{\mathrm{NN}}}=9.61$~TeV and 7~TeV respectively, employing a hybrid model encompassing IP-Glasma + MUSIC + iSS + UrQMD. The results of the clustered nuclear geometry are compared with those of the Woods\,--\,Saxon nuclear profile. Both initial and final state anisotropies are estimated. This study is thus one of its first kind, where the study of anisotropic flow coefficients for pO and OO collisions is presented using a hybrid hydrodynamics model. While the effect of $\alpha$-clustering in pO is found to be small, it is significant for each observable studied in OO collisions. It is also observed that the magnitude of this effect has a noteworthy dependence on the size of the \textsuperscript{4}He.

   ↳ hep-phhep-exhep-thnucl-ex+1PLB(2025)·7 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.