Tue·Apr 25, 2023Tuesday·April 25, 2023

1. 01*

   Measurements of high-n transitions in intermediate mass kaonic atoms by SIDDHARTA-2 at DA$\mathrm{\Phi }$NE

   F. Sgaramella (1)🇮🇹 · M. Tüchler (2 and 3)🇦🇹 · C. Amsler (2)🇦🇹 · M. Bazzi (1)🇮🇹 · D. Bosnar (4)🇭🇷 · M. Bragadireanu (5)🇷🇴 · M. Cargnelli (2)🇦🇹 · M. Carminati (6 and 7)🇮🇹 · A. Clozza (1)🇮🇹 · G. Deda (6 and 7)🇮🇹 · R. Del Grande (8 and 1)🇩🇪 · L. De Paolis (1)🇮🇹 and 29 other authors

   The SIDDHARTA-2 experiment installed at the DA$\mathrm{\Phi }$NE collider of INFN-LNF performed, for the first time, measurements of high-n transitions in intermediate mass kaonic atoms during the data taking campaigns of 2021 and 2022. Kaonic carbon, oxygen, nitrogen and aluminium transitions, which occur in the setup materials, were measured by using the kaons stopped in the gaseous helium target cell with aluminium frames and Kapton walls, and are reported in this paper. These new kaonic atoms measurements add valuable input to the kaonic atoms transitions data base, which is used as a reference for theories and models of the low-energy strong interaction between antikaon and nuclei. Moreover, these results pave the way for future dedicated kaonic atoms measurements through the whole periodic table and to a new era for the antikaon-nuclei studies at low energy.

   nucl-exphysics.ins-detEPJA(2023)·16 citations
2. 02*

   Hyperon signatures in the PANDA experiment at FAIR

   The PANDA Collaboration

   We present a detailed simulation study of the signatures from the sequential decays of the triple-strange pbar p -> {\Omega}+{\Omega}- -> K+{\Lambda}barK- {\Lambda} -> K+pbar{\pi}+K-p{\pi}- process in the PANDA central tracking system with focus on hit patterns and precise time measurement. We present a systematic approach for studying physics channels at the detector level and develop input criteria for tracking algorithms and trigger lines. Finally, we study the beam momentum dependence on the reconstruction efficiency for the PANDA detector.

   nucl-exhep-ex15 citations
3. 03*

   Coexisting single-particle excitations and octupole correlations in transitional nucleus ${}^{217}\mathbf{Ra}$

   Madhu · A. Y. Deo · Khamosh Yadav🇮🇳 · Dhananjaya Sahoo · Y. Y. Wang🇨🇳 · Y. K. Wang🇨🇳 · J. Meng🇨🇳 · Saket Suman · S. K. Tandel · A. Sharma🇨🇭 · I. Ahmed · K. Katre and 6 other authors

   The level structure of the transitional nucleus ${}^{217}\mathrm{Ra}$ has been extended with the addition of around 20 new transitions. The discrepancies between the placements of several transitions reported in the earlier studies are resolved. The newly-established negative-parity sequence at low excitation energies hints at the expected parity-doublet structures in this nucleus. The properties of the observed simplex bands are compared with that of similar bands in neighboring nuclei. Since the presence of parity-doublet structures reflect octupole correlations, theoretical calculations using reflection-asymmetric triaxial particle rotor model (RAT-PRM) have been performed. A comparison of the observed features of the simplex bands with the predictions of the RAT-PRM calculations suggests that ${}^{217}\mathrm{Ra}$ exhibits an intermediate the behavior between the extremes of spherical and octupole-deformed nuclei. The termination of the simplex bands at intermediate energies and the structures lying above reflect the dominance of the single-particle excitations at higher excitation energies.

   nucl-exnucl-thPRC(2023)·6 citations
4. 04*

   Closing the Door on the "Puzzle of Decoherence'' of Annihilation Quanta

   Siddharth Parashari · Damir Bosnar · Ivica Friščić · Zdenka Kuncic · Mihael Makek

   In para-positronium annihilation, exploration of the polarization correlations of the emerging gamma quanta has gained interest, since it offers a possibility to improve signal-to-background in medical imaging using positron emission tomography. The annihilation quanta, which are predicted to be in an entangled state, have orthogonal polarizations and this property may be exploited to discriminate them from two uncorrelated gamma photons contributing to the background. Recent experimental studies of polarization correlations of the annihilation quanta after a decoherence process induced by a prior Compton scattering of one of them, had rather different conclusions regarding the strength of the correlation after the decoherence, showing its puzzling nature. In the present work, we perform for the first time, a study of the polarization correlations of annihilation quanta after decoherence via Compton scattering in the angular range $0^{\circ }-50^{\circ }$ using single-layer gamma ray polarimeters. In addition, we compare the measured polarization correlations after Compton scattering at $30^{\circ }$ with an active and a passive scatterer element. The results indicate that the correlation, expressed in terms of the polarimetric modulation factor, shows no significant difference at small scattering angles ($0^{\circ }-30^{\circ }$) compared to the correlation measured for direct photons, while lower modulation was observed for $50^{\circ }$ scattering angle.

   ↳ quant-phnucl-exPLB(2024)·17 citations
5. 05*

   Table of hyperfine anomaly in atomic systems -- 2023

   J. R. Persson🇳🇴

   This table is an updated compilation of experimental values of the magnetic hyperfine anomaly in atomic and ionic systems. The literature search covers the period up to December 2022. A short discussion on general trends of the hyperfine anomaly and the theoretical developments are performed.

   ↳ physics.atom-phnucl-exAtom.Data Nucl.Data Tabl.(2023)·8 citations
6. 06*

   Probing the neutron-skin of unstable nuclei with heavy ion collisions

   Junping Yang🇨🇳 · Xiang Chen🇨🇳 · Ying Cui🇨🇳 · Zhuxia Li🇨🇳 · Yingxun Zhang🇨🇳

   To improve the constraints of symmetry energy at subsaturation density, measuring and accumulating more neutron skin data for neutron rich unstable nuclei is naturally required. Aiming to probe the neutron skin of unstable nuclei by using low-intermediate energy heavy ion collisions, we develop a new version of improved quantum molecular dynamics model, in which the neutron skin of the initial nucleus and the mean field potential in nucleon propagation are consistently treated. Our calculations show that the three observables, such as the cross sections of the primary projectile-like residues with $A>100$ (${\sigma }_{A>100}$), the difference of ${\sigma }_{A>100}$ between ${}^{132}$Sn+${}^{124}$Sn and ${}^{124}$Sn+${}^{124}$Sn systems ($\delta {\sigma }_{A>100}$), and the neutron to proton yield ratio ($R(n/p)$) in the transverse direction, could be used to measure the neutron skin of the unstable nuclei and to constrain the slope of the symmetry energy in the future.

   ↳ nucl-thnucl-exUniverse(2023)·3 citations
7. 07*

   Restoring Original Signal From Pile-up Signal using Deep Learning

   C. H. Kim🇰🇷 · S. Ahn🇰🇷 · K. Y. Chae🇰🇷 · J. Hooker🇺🇸 · G. V. Rogachev🇺🇸

   Pile-up signals are frequently produced in experimental physics. They create inaccurate physics data with high uncertainty and cause various problems. Therefore, the correction to pile-up signals is crucially required. In this study, we implemented a deep learning method to restore the original signals from the pile-up signals. We showed that a deep learning model could accurately reconstruct the original signal waveforms from the pile-up waveforms. By substituting the pile-up signals with the original signals predicted by the model, the energy and timing resolutions of the data are notably enhanced. The model implementation significantly improved the quality of the particle identification plot and particle tracks. This method is applicable to similar problems, such as separating multiple signals or correcting pile-up signals with other types of noises and backgrounds.

   ↳ physics.ins-detcs.LGeess.SPnucl-exNucl.Instrum.Meth.A(2023)·8 citations
8. 08*

   Comparisons of Matrices with Different Elements but Identical Eigenvalues

   Daren Sitchepping Fosso · Castaly Fan🇺🇸 · Larry Zamick

   We show 2 matrices that have identical eigenvalues but different eigenfunctions. This shows that in obtaining two body nuclear matrix elements empirically, it is not sufficient to consider only energy levels. Other quantities like transitions must also be included.

   ↳ nucl-thnucl-exquant-phIJMPE(2023)·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.