Mon·Jan 16, 2023Monday·January 16, 2023

1. 01*

   K${}_{\mathrm{S}}^0$ and $\Lambda (\overline{\Lambda })$ two-particle femtoscopic correlations in PbPb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV

   CMS Collaboration

   Two-particle correlations are presented for K${}_{\mathrm{S}}^0$, $\Lambda$, and $\overline{\Lambda }$ strange hadrons as a function of relative momentum in lead-lead collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV. The dataset corresponds to an integrated luminosity of 0.607 nb${}^{-1}$ and was collected using the CMS detector at the CERN LHC. These correlations are sensitive to quantum statistics and to final-state interactions between the particles. The source size extracted from the K${}_{\mathrm{S}}^0$K${}_{\mathrm{S}}^0$ correlations is found to decrease from 4.6 to 1.6 fm in going from central to peripheral collisions. Strong interaction scattering parameters (i.e., scattering length and effective range) are determined from the $\Lambda$K${}_{\mathrm{S}}^0$ and $\Lambda \Lambda$ (including their charge conjugates) correlations using the Lednick$\acute{y}$-Lyuboshitz model and are compared to theoretical and other experimental results.

   nucl-exhep-exPLB(2024)·15 citations
2. 02*

   Nuclear level densities and $\gamma$-ray strength functions in ${}^{120,124}$Sn isotopes: impact of Porter-Thomas fluctuations

   M. Markova🇳🇴 · A. C. Larsen🇳🇴 · P. von Neumann-Cosel🇩🇪 · S. Bassauer · A. Görgen🇳🇴 · M. Guttormsen🇳🇴 · F. L. Bello Garrote · H. C. Berg🇺🇸 · M. M. Bjørøen · T. K. Eriksen🇳🇴 · D. Gjestvang · J. Isaak and 11 other authors

   Nuclear level densities (NLDs) and $\gamma$-ray strength functions (GSFs) of ${}^{120,124}$Sn have been extracted with the Oslo method from proton-$\gamma$ coincidences in the ($p,p^{\prime }\gamma )$ reaction. The functional forms of the GSFs and NLDs have been further constrained with the Shape method by studying primary $\gamma$-transitions to the ground and first excited states.The NLDs demonstrate good agreement with the NLDs of ${}^{116,118,122}$Sn isotopes measured previously. Moreover, the extracted partial NLD of 1${}^{-}$ levels in ${}^{124}$Sn is shown to be in fair agreement with those deduced from spectra of relativistic Coulomb excitation in forward-angle inelastic proton scattering. The experimental NLDs have been applied to estimate the magnitude of the Porter-Thomas (PT) fluctuations. Within the PT fluctuations, we conclude that the GSFs for both isotopes can be considered to be independent of initial and final excitation energies, in accordance with the generalized Brink-Axel hypothesis. Particularly large fluctuations observed in the Shape-method GSFs present a considerable contribution to the uncertainty of the method, and may be one of the reasons for deviations from the Oslo-method strength at low $\gamma$-ray energies and low values of the NLD (below $\approx 1\cdot 10^3-2\cdot 10^3$ MeV${}^{-1}$).

   nucl-exPRC(2022)·21 citations
3. 03*

   Measurement of suppression of large-radius jets and its dependence on substructure in Pb+Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV with the ATLAS detector

   ATLAS Collaboration

   This letter presents a measurement of the nuclear modification factor of large-radius jets in $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV Pb+Pb collisions by the ATLAS experiment. The measurement is performed using 1.72 nb${}^{-1}$ and 257 pb${}^{-1}$ of Pb+Pb and $pp$ data, respectively. The large-radius jets are reconstructed with the anti-$k_t$ algorithm using a radius parameter of $R=1.0$, by re-clustering anti-$k_t$ $R=0.2$ jets, and are measured over the transverse momentum ($p_{\mathrm{T}}$) kinematic range of $158<p_{\mathrm{T}}<1000$ GeV and absolute pseudorapidity $|y|<2.0$. The large-radius jet constituents are further re-clustered using the $k_t$ algorithm in order to obtain the splitting parameters, $\sqrt{d_{12}}$ and $\Delta R_{12}$, which characterize the transverse momentum scale and angular separation for the hardest splitting in the jet, respectively. The nuclear modification factor, $R_{\mathrm{AA}}$, obtained by comparing the Pb+Pb jet yields to those in $pp$ collisions, is measured as a function of jet transverse momentum ($p_{\mathrm{T}}$) and $\sqrt{d_{12}}$ or $\Delta R_{12}$. A significant difference in the quenching of large-radius jets having single sub-jet and those with more complex substructure is observed. Systematic comparison of jet suppression in terms of $R_{\mathrm{AA}}$ for different jet definitions is also provided. Presented results support the hypothesis that jets with hard internal splittings lose more energy through quenching and provide a new perspective for understanding the role of jet structure in jet suppression.

   nucl-exhep-exPRL(2023)·50 citations
4. 04*

   Investigation of radiation hardness of silicon semiconductor detectors under irradiation with fission products of 252Cf nuclide

   N.V. Bazlov · A.V. Derbin🇷🇺 · I.S. Drachnev🇷🇺 · I. M. Kotina🇷🇺 · O. I. Konkov · I. S. Lomskaya🇷🇺 · M.S. Mikulich🇷🇺 · V.N. Muratova · D.A. Semenov🇷🇺 · M.V. Trushin🇷🇺 · E.V. Unzhakov🇷🇺

   Influence of the prolonged irradiation by fission products of 252Cf radionuclide on the operational parameters of silicon-lithium Si(Li) p-i-n detectors, Si surface barrier detectors and Si planar p+n detector was investigated. The obtained results revealed a linear shift of the fission fragment peaks positions towards the lower energies with increase of the irradiation dose for all investigated detectors. The rate of the peaks shift was found to depend strongly on the detector type and the strength of the electric field in the detectors active region, but not on the temperature of irradiation (room or liquid nitrogen temperature). Based on the obtained results, the possibility of integration of the investigated types of Si semiconductor detectors in a radionuclide neutron calibration source is considered.

   ↳ physics.ins-detnucl-exSt.Petersburg Polytech.Univ.J.Phys.Math.(2023)·0 citations
5. 05*

   Contribution of Nuclear Excitation Electromagnetic Form Factors in ${}^{12}\mathrm{C}$ and ${}^{16}\mathrm{O}$ to the Coulomb Sum Rule

   A. Bodek🇺🇸 · M. E. Christy🇺🇸

   We report on empirical parameterizations of longitudinal and transverse nuclear excitation electromagnetic form factors in ${}^{12}\mathrm{C}$ and ${}^{16}\mathrm{O}$. We extract the contribution of nuclear excitations to the Normalized Inelastic Coulomb Sum Rule (\csr) as a function of momentum transfer $\mathbf{q}$ and find that it is significant (0.29$\pm$0.030 at $\mathbf{q}$= 0.22 GeV). The total contributions of nuclear excitations to $S_L(\mathbf{q})$ in ${}^{12}\mathrm{C}$ and ${}^{16}\mathrm{O}$ are found to be equal within the uncertainties. Since the cross sections for nuclear excitations are significant, the radiative tails from nuclear excitations should be included in precise calculations of radiative corrections to quasielastic electron scattering at low $\mathbf{q}$ and deep-inelastic electron scattering at large energy transfers $\nu$. The parameterizations also serve as a benchmark in testing theoretical modeling of cross sections for excitation of nuclear states in electron and neutrino interactions on nuclear targets at low energies.

   ↳ nucl-thhep-phnucl-exPRC(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.