Thu·Mar 23, 2023Thursday·March 23, 2023

1. 01*

   Beta-delayed neutron spectroscopy of ${}^{133}$In

   Z. Y. Xu🇺🇸 · M. Madurga🇺🇸 · R. Grzywacz🇺🇸 · T. T. King🇺🇸 · A. Algora🇪🇸 · A. N. Andreyev🇬🇧 · J. Benito🇪🇸 · T. Berry🇬🇧 · M. J. G. Borge🇪🇸 · C. Costache🇷🇴 · H. De Witte🇧🇪 · A. Fijalkowska🇵🇱 and 37 other authors

   The decay properties of ${}^{133}$In were studied in detail at the ISOLDE Decay Station (IDS). The implementation of the Resonance Ionization Laser Ion Source (RILIS) allowed separate measurements of its $9/2^{+}$ ground state (${}^{133g}$In) and $1/2^{-}$ isomer (${}^{133m}$In). With the use of $\beta$-delayed neutron and $\gamma$ spectroscopy, the decay strengths above the neutron separation energy were quantified in this neutron-rich nucleus for the first time. The allowed Gamow-Teller transition $9/2^{+}\to 7/2^{+}$ was located at 5.92 MeV in the ${}^{133g}$In decay with a logft = 4.7(1). In addition, several neutron-unbound states were populated at lower excitation energies by the First-Forbidden decays of ${}^{133g,m}$In. We assigned spins and parities to those neutron-unbound states based on the $\beta$-decay selection rules, the logft values, and systematics.

   nucl-exPRC(2023)·12 citations
2. 02*

   Production of neptunium and plutonium nuclides from uranium carbide using 1.4-GeV protons

   M. Au (1 and 2)🇨🇭 · M. Athanasakis-Kaklamanakis (1 and 3)🇨🇭 · L. Nies (1 and 4)🇨🇭 · R. Heinke (1)🇨🇭 · K. Chrysalidis (1)🇨🇭 · U. Köster (1 and 5)🇨🇭 · P. Kunz (6)🇨🇦 · B. Marsh (1)🇨🇭 · M. Mougeot (1 and 7)🇨🇭 · L. Schweikhard (4)🇩🇪 · S. Stegemann (1)🇨🇭 · Y. Vila Gracia (1)🇨🇭 · Ch. E. Düllmann (2 and 8 and 9)🇩🇪 · S. Rothe (1) ((1) European Organization for Nuclear Research (CERN), Geneva, Switzerland, (2) Johannes Gutenberg-Universität Mainz, Mainz, Germany, (3) KU Leuven, Leuven, Belgium, (4) University of Greifswald, Greifswald, Germany, (5) Institut Laue-Langevin, Grenoble, France, (6) TRIUMF, Vancouver, Canada, (7) Max Planck Institut für Kernphysik, Heidelberg, Germany, (8) GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany, (9) Helmholtz Institute Mainz, Mainz, Germany)🇨🇭

   Accelerator-based techniques are one of the leading ways to produce radioactive nuclei. In this work, the Isotope Separation On-Line method was employed at the CERN-ISOLDE facility to produce neptunium and plutonium from a uranium carbide target material using 1.4-GeV protons. Neptunium and plutonium were laser-ionized and extracted as 30-keV ion beams. A Multi-Reflection Time-of-Flight mass spectrometer was used for ion identification by means of time-of-flight measurements as well as for isobaric separation. Isotope shifts were investigated for the 395.6-nm ground state transition in ${}^{236,237,239}$Np and the 413.4-nm ground state transition in ${}^{236,239,240}$Pu. Rates of ${}^{235-241}$Np and ${}^{234-241}$Pu ions were measured and compared with predictions of in-target production mechanisms simulated with GEANT4 and FLUKA to elucidate the processes by which these nuclei, which contain more protons than the target nucleus, are formed. ${}^{241}$Pu is the heaviest nuclide produced and identified at a proton-accelerator-driven facility to date. We report the availability of neptunium and plutonium as two additional elements at CERN-ISOLDE and discuss the limit of accelerator-based isotope production at high-energy proton accelerator facilities for nuclides in the actinide region.

   nucl-exPRC(2023)·3 citations
3. 03*

   $\beta$-decay spectroscopy of neutron-deficient nuclei

   S.E.A. Orrigo🇪🇸 · B. Rubio🇪🇸 · W. Gelletly🇬🇧

   A systematic study of the $\beta$-decay of neutron-deficient nuclei has been carried out and has provided spectroscopic information of importance for both nuclear structure and nuclear astrophysics. Following an overview of the most relevant achievements, we focus on the latest results on the $\beta$ decay of ${}^{60}$Ge and ${}^{62}$Ge. We also summarise our results on the mass excesses in comparison with systematics and a recent measurement. Finally, we present updated half-life trends for $T_z=$ -1/2, -1 and -2 neutron-deficient nuclides.

   nucl-exEPJ Web Conf.(2023)·0 citations
4. 04*

   Precise determination of quadrupole and hexadecapole deformation parameters of the $sd$-shell nucleus, ${}^{28}$Si

   Y. K. Gupta🇮🇳 · V. B. Katariy · G. K. Prajapati🇮🇳 · K. Hagino🇯🇵 · D. Patel🇮🇳 · V. Ranga🇮🇳 · L. S. Danu🇮🇳 · A. Pal🇮🇳 · B. N. Joshi🇮🇳 · S. Dubey🇺🇸 · V. V. Desai🇮🇳 · S. Panwar🇮🇳 and 8 other authors

   Quasi-elastic (QEL) scattering measurements have been performed using ${}^{28}$Si projectile off a ${}^{90}$Zr target at energies around the Coulomb barrier. A Bayesian analysis within the framework of coupled channels (CC) calculations is performed in a large parameter space of quadrupole and hexadecapole deformations (${\beta }_2$ and ${\beta }_4$) of ${}^{28}$Si. Our results clearly show that ${}^{28}$Si is an oblate shaped nucleus with ${\beta }_2$=-$0.38\pm 0.01$ which is in excellent agreement with electromagnetic probes. A precise value of hexadecapole deformation for ${}^{28}$Si, ${\beta }_4$=+$0.03\pm 0.01$, along with a consistent value of quadrupole deformation has now been determined for the first time using QEL scattering. A remarkable agreement between the experimental ${\beta }_4$ value of ${}^{28}$Si and Skyrme-Hartree-Fock based calculations is obtained. The QEL results obtained previously for ${}^{24}$Mg (prolate) and the present result for ${}^{28}$Si (oblate) hereby affirm the strong sensitivity of the quasi-elastic scattering to ground state deformations, thus reinforcing its suitability as a potential probe for rare exotic nuclei.

   nucl-exnucl-thPLB(2023)·22 citations
5. 05*

   Non-forward radiative corrections to electron-carbon scattering

   M. Mihovilovič · A. B. Weber · P. Achenbach · M. Bajec · T. Beranek · J. Beričič · J. C. Bernauer · D. Bosnar · R. Böhm · M. Cardinali · L. Correa · L. Debenjak and 28 other authors

   Radiative corrections to elastic scattering represent an important part of the interpretation of electron-induced nuclear reactions at small energy transfers, where they make for a dominant part of background. Here we present and validate a new event generator for mimicking QED radiative processes in electron-carbon scattering that exactly calculates the coherent sum of the Bethe-Heitler amplitudes for the leading diagrams and can be reliably employed for a more robust determination of inelastic cross-sections.

   ↳ hep-phnucl-exEPJA(2023)·2 citations
6. 06*

   Is it possible to simulate the cosmological stage of the nucleon mass generation?

   Vladimir I. Komarov🇷🇺

   The mechanism of elementary particle mass generation is a fundamental issue of physics. While cardinal progress has recently been achieved in the case of leptons and current quarks through the Brout-Engler-Higgs mechanism, this issue is at the stage of searching for the constituent quarks forming the nucleon mass. A deep similarity is noted in the paper between the constituent quark states arising in central inelastic $NN$ collisions within a certain energy interval and the QCD matter states at the cosmological stage of nucleon mass generation. This gives rise to special attention to the investigation of both issues.

   ↳ hep-phnucl-ex0 citations
7. 07*

   Flavor hierarchy of parton energy loss in quark-gluon plasma from a Bayesian analysis

   Wen-Jing Xing🇨🇳 · Shanshan Cao🇨🇳 · Guang-You Qin🇨🇳

   The quenching of light and heavy flavor hadrons in relativistic heavy-ion collisions probes the color and flavor dependences of parton energy loss through a color-deconfined quark-gluon plasma (QGP), and thus reveals the properties of QCD matter at extremely high density and temperature. By combining a next-to-leading order perturbative QCD calculation of parton production, a general ansatz of parton energy loss functions and parton fragmentation functions, we calculate the nuclear modification of various hadron species -- charged hadrons, $D$ mesons and $B$-decayed $J/\psi$ -- over a wide transverse momentum regime. Comparing our calculations to the experimental data using the Bayesian statistical analysis, we perform a first simultaneous extraction of the energy loss functions of gluons ($g$), light quarks ($q$), charm quarks ($c$) and bottom quarks ($b$) inside the QGP. We find that the average parton energy loss at high energies follows the expected hierarchy of $⟨\Delta E_g⟩>⟨\Delta E_q⟩\sim ⟨\Delta E_c⟩>⟨\Delta E_b⟩$, while the parton energy loss distribution can further test the QCD calculations of parton interaction with the dense nuclear matter. We also find that the reduction of experimental uncertainties can significantly improve the precision of the extracted parton energy loss functions inside the QGP.

   ↳ hep-phhep-exnucl-exnucl-thPLB(2024)·19 citations
8. 08*

   Exclusive heavy vector meson photoproduction on nuclei in NLO perturbative QCD

   K.J. Eskola (Jyvaskyla U. and Helsinki U.)🇫🇮 · V. Guzey (Jyvaskyla U. and Helsinki U.)🇫🇮 · T. Löytäinen (Jyvaskyla U. and Helsinki U.)🇫🇮 · H. Paukkunen (Jyvaskyla U. and Helsinki U.)🇫🇮 · C.A. Flett (IJCLab, Orsay)🇫🇷

   We make predictions for the cross section of coherent $J/\psi$ photoproduction in Pb-Pb and O-O ultraperipheral collisions (UPCs) at the LHC as a function of the $J/\psi$ rapidity $y$ in the framework of collinear factorization and next-to-leading order (NLO) perturbative QCD. We quantify the strong scale dependence and significant uncertainties due to nuclear PDFs and show that our approach provides a reasonable description of the LHC data on coherent $J/\psi$ photoproduction in Pb-Pb UPCs. We demonstrate that these uncertainties are reduced by approximately a factor of 10 in the scaled ratio of the O-O and Pb-Pb UPC cross sections. Our analysis indicates the dominance of the quark contribution to the UPC cross section at central rapidities, which affects the interpretation of the UPC data.

   ↳ hep-phhep-exnucl-exActa Phys.Polon.Supp.(2023)·1 citation

* 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.