Wed·Nov 9, 2022Wednesday·November 9, 2022

1. 01*

   PANDORA project: photo-nuclear reactions below $A=60$

   A. Tamii · L. Pellegri · P.-A. Söderström · D. Allard · S. Goriely · T. Inakura · E. Khan · E. Kido · M. Kimura · E. Litvinova · S. Nagataki · P. von Neumann-Cosel and 69 other authors

   Photo-nuclear reactions of light nuclei below a mass of $A=60$ are studied experimentally and theoretically by the PANDORA (Photo-Absorption of Nuclei and Decay Observation for Reactions in Astrophysics) project. Two experimental methods, virtual-photon excitation by proton scattering and real-photo absorption by a high-brilliance gamma-ray beam produced by laser Compton scattering, will be applied to measure the photo-absorption cross sections and the decay branching ratio of each decay channel as a function of the photon energy. Several nuclear models, e.g. anti-symmetrized molecular dynamics, mean-field type models, a large-scale shell model, and ab initio models, will be employed to predict the photo-nuclear reactions. The uncertainty in the model predictions will be evaluated from the discrepancies between the model predictions and the experimental data. The data and the predictions will be implemented in a general reaction calculation code TALYS . The results will be applied to the simulation of the photo-disintegration process of ultra-high-energy cosmic rays in inter-galactic propagation.

   nucl-exastro-ph.HEnucl-thEPJA(2023)·30 citations
2. 02*

   The ALICE experiment: a journey through QCD

   ALICE Collaboration

   The ALICE experiment was proposed in 1993, to study strongly-interacting matter at extreme energy densities and temperatures. This proposal entailed a comprehensive investigation of nuclear collisions at the LHC. Its physics programme initially focused on the determination of the properties of the quark-gluon plasma (QGP), a deconfined state of quarks and gluons, created in such collisions. The ALICE physics programme has been extended to cover a broader ensemble of observables related to Quantum Chromodynamics (QCD), the theory of strong interactions. The experiment has studied Pb-Pb, Xe-Xe, p-Pb and pp collisions in the multi-TeV centre of mass energy range, during the Run 1-2 data-taking periods at the LHC (2009-2018). The aim of this review is to summarise the key ALICE physics results in this endeavor, and to discuss their implications on the current understanding of the macroscopic and microscopic properties of strongly-interacting matter at the highest temperatures reached in the laboratory. It will review the latest findings on the properties of the QGP created by heavy-ion collisions at LHC energies, and describe the surprising QGP-like effects in pp and p-Pb collisions. Measurements of few-body QCD interactions, and their impact in unraveling the structure of hadrons and hadronic interactions, will be discussed. ALICE results relevant for physics topics outside the realm of QCD will also be touched upon. Finally, prospects for future measurements with the ALICE detector in the context of its planned upgrades will also be briefly described.

   nucl-exhep-exEPJC(2024)·484 citations
3. 03*

   Fast Neutron Spectroscopy with a High-pressure Nitrogen-filled Large Volume Spherical Proportional Counter

   I. Giomataris🇫🇷 · I. Katsioulas🇬🇧 · P. Knights🇬🇧 · I. Manthos🇬🇧 · J. Matthews🇬🇧 · T. Neep🇬🇧 · K. Nikolopoulos🇬🇧 · T.Papaevangelou🇫🇷 · B.Phoenix🇬🇧 · R.Ward🇬🇧

   We present a fast neutron spectroscopy system based on a nitrogen-filled, large volume gaseous detector, the Spherical Proportional Counter. The system has been successfully operated up to gas pressure of 1.5 bar. Neutron energy is estimated through measurement of the 14N(n,a)11B and 14N(n,p)14C reaction products. These reactions have comparable cross sections and Q-values with the 3He(n,p)3H reaction making nitrogen a good alternative to 3He use for fast neutron detection. Two detectors were built at the University of Birmingham and are currently used for the measurement of fast and thermal neutrons in the University of Birmingham and the Boulby underground laboratory, respectively.

   ↳ hep-exnucl-ex2021 IEEE Nuclear Science Symposium and M…·0 citations
4. 04*

   Electromagnetic fields in ultra-peripheral relativistic heavy-ion collisions

   Jie Zhao🇨🇳 · Jinhui Chen🇨🇳 · Xu-Guang Huang🇨🇳 · Yu-Gang Ma🇨🇳

   Ultraperipheral heavy-ion collisions (UPCs) offer unique opportunities to study processes under strong electromagnetic fields. In these collisions, highly charged fast-moving ions carry strong electromagnetic fields that can be effectively treated as photon fluxes. The exchange of photons can induce photonuclear and two-photon interactions, and excite ions. This excitation of the ions results in Coulomb dissociation with the emission of photons, neutrons, and other particles. Additionally, the electromagnetic fields generated by the ions can be sufficiently strong to enforce mutual interactions between the two colliding ions. Consequently, the two colliding ions experienced an electromagnetic force that pushed them in opposite directions, causing a back-to-back correlation in the emitted neutrons. Using a Monte Carlo simulation, we qualitatively demonstrated that the above electromagnetic effect is large enough to be observed in UPCs, which would provide a clear means to study strong electromagnetic fields and their effects.

   ↳ nucl-thnucl-exNucl.Sci.Tech.(2024)·32 citations
5. 05*

   Study of structure and radii for ${}^{20-31}$Na isotopes using microscopic interactions

   Subhrajit Sahoo🇮🇳 · Praveen C. Srivastava🇮🇳 · Toshio Suzuki

   In this work, Na isotopes with mass varying from $A=$ 20 to 31 have been studied using DJ16A, JISP16 and N3LO microscopic effective interactions in the $sd$-shell. These effective interactions are derived for $sd$-shell using no-core shell model wavefunctions and a unitary transformation method. We have also performed calculation with IMSRG effective interactions targeted for a particular nucleus. The studies include a detailed analysis of ground state binding energy, low-lying spectra, and electromagnetic properties such as reduced electric quadrupole transition strengths, quadrupole and magnetic dipole moments of the Na chain. The results obtained from these microscopic effective interactions were compared with the experimental data as well as with the results of phenomenological interaction USDB. The charge radii of Na isotopes are evaluated using shell model harmonic oscillator wave functions. In addition to charge radii, matter radii and neutron skin thickness in the Na chain are discussed with a focus on neutron-deficient Na isotopes.

   ↳ nucl-thnucl-exNPA(2023)·12 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.