Mon·Nov 14, 2022Monday·November 14, 2022

1. 01*

   A fast-rotating pear-shaped nucleus

   A. Karmakar · P. Datta · Soumik Bhattacharya🇮🇳 · Shabir Dar🇮🇳 · S. Bhattacharya · G. Mukherjee🇮🇳 · H. Pai🇷🇴 · S. Basu · S. Nandi🇮🇳 · S. S. Nayak · Sneha Das · R. Raut🇮🇳 and 6 other authors

   The spectroscopic studies have identified few Actinide and Lanthanide nuclei of the periodic table, which can assume the pear shape. The low frequency collective rotation of these nuclei has been established by determining the band structure of the excited levels and their gamma decay rates. In this article, we report the rotation of a pear-shaped nucleus in 100 Ru, which rotates nearly three times faster than the previously known cases. The three novel consequences of this fast rotation are: the realization of a pear-shape in an excited state, its moment of inertia becoming a constant of motion and its shape evolution. These inferences have been arrived at by comparing the characteristics of the rotational band of 100 Ru with three of the best-known examples of a rotating pear-shaped nucleus and through the theoretical interpretation of the data. The observation of a pear-shaped nucleus in the lighter mass region opens up the possibility of a systematic study of the effects of fast rotation on this shape.

   nucl-exnucl-th0 citations
2. 02*

   Toward a description of the centrality dependence of the charge balance function in the HYDJET++ model

   A.S. Chernyshov🇷🇺 · G.Kh. Eyyubova🇷🇺 · V.L. Korotkikh🇷🇺 · I.P. Lokhtin🇷🇺 · L.V. Malinina🇷🇺 · S.V. Petrushanko🇷🇺 · A.M. Snigirev🇷🇺 · E.E. Zabrodin🇳🇴

   Data from the Large Hadron Collider on the charge balance function in Pb+Pb collisions at center-of-mass energy 2.76~TeV per nucleon pair are analyzed and interpreted within the framework of the \hydjet++ model. This model allows us to qualitatively reproduce the experimentally observed centrality dependence of the balance function widths at relatively low transverse momentum intervals due to the different charge creation mechanisms in soft and hard processes. However, a fully adequate description of the balance function in these intervals implies an essential modification of the model by including exact charge conservation via the canonical rather than the grand canonical ensemble. A procedure is proposed for introducing charge correlations into the thermal model without changing other model parameters. With increasing transverse momenta, the default model results describe the experimental data much better because the contribution of the soft component of the model is significantly reduced in these transverse momentum intervals. In practical terms, there is a transition to a single source of charge correlations, namely, charge correlations in jets in which exact charge conservation holds at each stage.

   ↳ nucl-thhep-phnucl-exCPC(2023)·8 citations
3. 03*

   Direct dark matter searches with the full data set of XMASS-I

   XMASS Collaboration : K. Abe🇯🇵 · K. Hiraide🇯🇵 · N. Kato🇯🇵 · S. Moriyama🇯🇵 · M. Nakahata🇯🇵 · K. Sato🇯🇵 · H. Sekiya🇯🇵 · T. Suzuki🇯🇵 · Y. Suzuki🇯🇵 · A. Takeda🇯🇵 · B. S. Yang🇯🇵 · N. Y. Kim🇰🇷 and 19 other authors

   Various WIMP dark matter searches using the full data set of XMASS-I, a single-phase liquid xenon detector, are reported in this paper. Stable XMASS-I data taking accumulated a total live time of 1590.9 days between November 20, 2013 and February 1, 2019 with an analysis threshold of $1.0\mathrm{ke}{\mathrm{V}}_{\mathrm{ee}}$. In the latter half of data taking a lower analysis threshold of $0.5\mathrm{ke}{\mathrm{V}}_{\mathrm{ee}}$ was also available through a new low threshold trigger. Searching for a WIMP signal in the detector's 97~kg fiducial volume yielded a limit on the WIMP-nucleon scattering cross section of $1.4\times 10^{-44}\mathrm{c}{\mathrm{m}}^2$ for a $60GeV/{\mathrm{c}}^2$ WIMP at the 90$\%$ confidence level. We also searched for WIMP induced annual modulation signatures in the detector's whole target volume, containing 832~kg of liquid xenon. For nuclear recoils of a $8GeV/{\mathrm{c}}^2$ WIMP this analysis yielded a 90\% CL cross section limit of $2.3\times 10^{-42}\mathrm{c}{\mathrm{m}}^2$. At a WIMP mass of $0.5GeV/{\mathrm{c}}^2$ the Migdal effect and Bremsstrahlung signatures were evaluated and lead to 90\% CL cross section limits of $1.4\times 10^{-35}\mathrm{c}{\mathrm{m}}^2$ and $1.1\times 10^{-33}\mathrm{c}{\mathrm{m}}^2$ respectively.

   ↳ astro-ph.COhep-exnucl-exphysics.ins-detPRD(2023)·16 citations
4. 04*

   Perspectives on few-body cluster structures in exotic nuclei

   D. Bazin🇺🇸 · K. Becker🇺🇸 · F. Bonaiti🇩🇪 · Ch. Elster🇺🇸 · K. Fossez🇺🇸 · T. Frederico🇧🇷 · A. Gnech🇺🇸 · C. Hebborn🇺🇸 · M. Higgins🇺🇸 · L. Hlophe🇺🇸 · B. Kay🇺🇸 · S. König🇺🇸 and 7 other authors

   It is a fascinating phenomenon in nuclear physics that states with a pronounced few-body structure can emerge from the complex dynamics of many nucleons. Such halo or cluster states often appear near the boundaries of nuclear stability. As such, they are an important part of the experimental program beginning at the Facility for Rare Isotope Beams (FRIB). A concerted effort of theory and experiment is necessary both to analyze experiments involving effective few-body states, as well as to constrain and refine theories of the nuclear force in light of new data from these experiments. As a contribution to exactly this effort, this paper compiles a collection of ``perspectives'' that emerged out of the Topical Program ``Few-body cluster structures in exotic nuclei and their role in FRIB experiments'' that was held at FRIB in August 2022 and brought together theorists and experimentalists working on this topic.

   ↳ nucl-thnucl-exFew Body Syst.(2023)·9 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.