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Related papers: Shell-gap reduced level densities in $^{89,90}$Y

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It is almost 80 years since Hans Bethe described the level density as a non-interacting gas of protons and neutrons. In all these years, experimental data were interpreted within this picture of a fermionic gas. However, the renewed…

Level density $\rho(E,N,Z)$ is calculated for the two-component close- and open-shell nuclei with a given energy $E$, and neutron $N$ and proton $Z$ numbers, taking into account pairing effects within the microscopic-macroscopic approach…

Nuclear Theory · Physics 2023-08-16 A. G. Magner , A. I. Sanzhur , S. N. Fedotkin , A. I. Levon , U. V. Grygoriev , S. Shlomo

Nuclear level density and $\gamma$-ray strength functions of $^{121,122}$Sn below the neutron separation energy are extracted with the Oslo method using the ($^3$He,$^3$He$^\prime\gamma$) and ($^3$He,$\alpha \gamma$) reactions. The level…

Level density $\rho(E,A)$ is derived for a one-component nucleon system with a given energy $E$ and particle number $A$ within the mean-field semiclassical periodic-orbit theory beyond the saddle-point method of the Fermi gas model. We…

Nuclear Theory · Physics 2021-10-20 A. G. Magner , A. I. Sanzhur , S. N. Fedotkin , A. I. Levon , S. Shlomo

A method to extract primary $\gamma$-ray spectra from particle-$\gamma$ coincidences at excitation energies up to the neutron binding energy is described. From these spectra, the level density and $\gamma$-ray strength function can be…

Nuclear Experiment · Physics 2007-05-23 M. Guttormsen , M. Hjorth-Jensen , J. Rekstad , S. Siem , A. Schiller , A. Voinov

The nuclear level density (NLD) and the $\gamma$-ray strength function (GSF) of the neutron-deficient $^{109}$In isotope were extracted for the first time with data from the $^{106}$Cd$(\alpha,p\gamma)^{109}$In reaction using a combination…

Studies of one-body density matrices (ODM) are performed in various correlation methods, such as the Jastrow method, the correlated basis function method, the Green's function method and the generator coordinate method aiming to extract the…

Nuclear Theory · Physics 2007-05-23 A. N. Antonov , M. K. Gaidarov , M. V. Ivanov , K. A. Pavlova , C. Giusti

Starting from an independent-particle model with a finite and arbitrary set of single-particle energies, we develop an analytical approximation to the many-body level density $\rho_A(E)$ and to particle-hole densities. We use exact…

Nuclear Theory · Physics 2013-09-30 Adriana Pálffy , Hans A. Weidenmüller

We compare $237$ Lyman-$\alpha$ (Ly$\alpha$) spectra of the "MUSE-Wide survey" (Herenz et al. 2017) to a suite of radiative transfer simulations consisting of a central luminous source within a concentric, moving shell of neutral gas, and…

Astrophysics of Galaxies · Physics 2017-12-20 Max Gronke

We extend the shell-model Monte Carlo applications to the rare-earth region to include the odd-even nucleus ${}^{161}$Dy. The projection on an odd number of particles leads to a sign problem at low temperatures making it impractical to…

Nuclear Theory · Physics 2015-06-05 Cem Özen , Yoram Alhassid , Hitoshi Nakada

A microscopic nuclear level-density model is presented. The model is a completely combinatorial (micro-canonical) model based on the folded-Yukawa single-particle potential and includes explicit treatment of pairing, rotational and…

Nuclear Theory · Physics 2009-07-26 H. Uhrenholt , S. Åberg , P. Möller , T. Ichikawa

We apply the realistic shell model which includes the coupling between many-particle (quasi-)bound states and the continuum of one-particle scattering states to the spectroscopy of mirror nuclei: $^8$B and $^8$Li, as well as to the…

Nuclear Theory · Physics 2009-10-31 K. Bennaceur , F. Nowacki , J. Okolowicz , M. Ploszajczak

We investigate the nature and impact of shell effects on nuclear level density (NLD) and particle emission probability as a function of temperature in a microscopic theoretical framework of Statistical Model for nuclei ranging from neutron…

Nuclear Theory · Physics 2023-03-03 Mamta Aggarwal

The measurement of a reaction cross section from a pulse height spectrum is a ubiquitous problem in experimental nuclear physics. In $\gamma$-ray spectroscopy, this is accomplished frequently by measuring the intensity of full-energy…

Data Analysis, Statistics and Probability · Physics 2017-10-05 J. R. Dermigny , C. Iliadis , M. Q. Buckner , K. J. Kelly

We review recent advances in the shell model Monte Carlo approach for the microscopic calculation of statistical and collective properties of nuclei. We discuss applications to the calculation of (i) level densities in nickel isotopes,…

Nuclear Theory · Physics 2016-01-05 Y. Alhassid

Neutrino reaction cross-sections, $(\nu_\mu,\mu^-)$, $(\nu_e,e^-)$, $\mu$-capture and photoabsorption rates on $^{12}$C are computed within a large-basis shell-model framework, which included excitations up to $4\hbar\omega$. When…

Nuclear Theory · Physics 2009-10-31 A. C. Hayes , I. S. Towner

We report investigation of near-resonance light scattering from a cold and dense atomic gas of $^{87}$Rb atoms. Measurements are made for probe frequencies tuned near the $F=2\to F'=3$ nearly closed hyperfine transition, with particular…

Atomic Physics · Physics 2020-03-25 K. J. Kemp , S. J. Roof , M. D. Havey , I. M. Sokolov , D. V. Kupriyanov , W. Guerin

The high spin excited states of Lanthanum isotopes $^{140-143}$La, above the $N=82$ closed shell, have been populated in fission reactions. The prompt $\gamma$-ray transitions were measured using two complementary methods; a) in coincidence…

Frequency shifts, radiative decay rates, the Ohmic loss contribution to the nonradiative decay rates, fluorescence yields, and photobleaching of a two-level atom radiating anywhere inside or outside a complex spherical nanoshell, i.e. a…

Quantum Physics · Physics 2007-05-23 Alexander Moroz

Shell effects reflects irregularities of physical quantities caused by a discrete energy spectrum. The theory of the shell effects by Kirzhnits and Shpatakovskaya is valid only at relatively low densities providing for oscillations of…

Plasma Physics · Physics 2016-08-30 Sergey Dyachkov , Pavel Levashov