Wed·Apr 10, 2024Wednesday·April 10, 2024

1. 01*

   Nuclear charge radii of germanium isotopes around $N$ = 40

   S. J. Wang🇨🇳 · A. Kanellakopoulos🇧🇪 · X.F. Yang🇨🇳 · S. W. Bai🇨🇳 · J. Billowes🇬🇧 · M. L. Bissell🇬🇧 · K. Blaum🇩🇪 · B. Cheal🇬🇧 · C. S. Devlin🇬🇧 · R. F. Garcia Ruiz🇺🇸 · J. Z. Han🇨🇳 · H. Heylen🇨🇭 and 17 other authors

   Collinear laser spectroscopy measurements were performed on ${}^{68-74}$Ge isotopes ($Z=32$) at ISOLDE-CERN, by probing the $4s^{2}4p^2{}^3{P}_1\to 4s^{2}4p5s{}^3{P}_1^o$ atomic transition (269~nm) of germanium. Nuclear charge radii are determined via the measured isotope shifts, revealing a larger local variation than the neighboring isotopic chains. Nuclear density functional theory with the Fayans functionals Fy($\Delta r$,HFB) and Fy(IVP), and the SV-min Skyrme describes the experimental data for the differential charge radii $\delta ⟨r^2⟩$ and charge radii $R_{\mathrm{c}}$ within the theoretical uncertainties. The observed large variation in the charge radii of germanium isotopes is better accounted for by theoretical models incorporating ground state quadrupole correlations. This suggests that the polarization effects due to pairing and deformation contribute to the observed large odd-even staggering in the charge radii of the Ge isotopic chain.

   nucl-exnucl-thPLB(2024)·15 citations
2. 02*

   Shape transition and coexistence in Te isotopes studied with the quadrupole collective Hamiltonian based on a relativistic energy density functional

   K. Suzuki🇩🇪 · K. Nomura🇯🇵

   Evolution and coexistence of shape and the related spectroscopic properties of even-even Te isotopes are investigated within the quadrupole collective model that is based on the nuclear density functional theory. By means of the constrained self-consistent mean-field calculations performed within the relativistic Hartree-Bogoliubov method with a choice of the energy density functional and pairing interaction, the deformation-dependent mass parameters and moments of inertia as well as collective potential of the triaxial quadrupole collective Hamiltonian are completely determined. The collective model produces for the near mid-shell nuclei, e.g., ${}^{116}$Te and ${}^{118}$Te, the low-energy $0_2^{+}$ state, which can be interpreted as the intruder state originating from the strongly deformed prolate minimum in the potential energy surface, along with the $0_1^{+}$ ground state that is attributed to the normal state based on a weakly oblate deformed global minimum. The collective model calculation suggests a parabolic behavior of the $0_2^{+}$ energy level near the neutron mid-shell $N=66$, as observed experimentally. Sensitivities of the calculated low-energy spectra to the pairing strength and collective mass parameters are analyzed.

   ↳ nucl-thnucl-exPRC(2024)·4 citations
3. 03*

   Three ways to decipher the nature of exotic hadrons: multiplets, three-body hadronic molecules, and correlation functions

   Ming-Zhu Liu🇨🇳 · Ya-Wen Pan🇨🇳 · Zhi-Wei Liu🇨🇳 · Tian-Wei Wu🇨🇳 · Jun-Xu Lu🇨🇳 · Li-Sheng Geng🇨🇳

   In the past two decades, a plethora of hadronic states beyond the conventional quark model of $q\bar{q}$ mesons and $qqq$ baryons have been observed experimentally, which motivated extensive studies to understand their nature and the non-perturbative strong interaction. Since most of these exotic states are near the mass thresholds of a pair of conventional hadrons, the prevailing picture is that they are primarily hadronic molecules. In principle, one can verify the molecular nature of these states by thoroughly comparing their masses, decay widths, and production rates in a particular picture with experimental data. However, this is difficult or impossible. First, quantum mechanics allows for the mixing of configurations allowed by symmetries and quantum numbers. Second, data are relatively scarce because of their small production rates and the many difficulties in the experimental measurements. As a result, other alternatives need to be explored. This review summarizes three such approaches that can help disentangle the nature of the many exotic hadrons discovered. In the first approach, based on the molecular interpretations for some exotic states, we study the likely existence of multiplets of hadronic molecules related by various symmetries, such as isospin symmetry, SU(3)-flavor symmetry, heavy quark spin/flavor symmetry, and heavy antiquark diquark symmetry. In the second approach, starting from some hadronic molecular candidates, one can derive the underlying hadron-hadron interactions. With these interactions, one can study related three-body systems and check whether three-body bound states/resonances exist. In the third approach, one can turn to the femtoscopy technique to derive the hadron-hadron interactions, hence inaccessible. This technique provided an unprecedented opportunity to understand the interactions between unstable hadrons.

   ↳ hep-phhep-exhep-latnucl-ex+1Phys.Rept.(2025)·218 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.