Parity dependence of Nuclear Level Density

A. Badola¹ , S.K. Singhal² , M. Bhatnagar³

1. Department of Physics, DIT University, Dehradun, India.
2. Department of Physics, DIT University, Dehradun, India.
3. Government Polytechnic, Saharanpur, India.
4. Department of Physics, DIT University, Dehradun, India.

Correspondence should be addressed to: amitbadola555@gmail.com.

Section:Research Paper, Product Type: Isroset-Journal
Vol.6 , Issue.3 , pp.18-24, Jun-2018

CrossRef-DOI:   https://doi.org/10.26438/ijsrpas/v6i3.1824

Online published on Jun 30, 2018

Copyright © A. Badola, S.K. Singhal, M. Bhatnagar . This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
 

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Abstract :
The knowledge parity dependent nuclear level density (E, J, π) is very essential in low energy nuclear physics as it is used to evaluate nuclear cross-sections in nuclear reaction calculations. At low excitation energies, astrophysical reaction rates are sensitive to the parity distribution. However, the information of level density is confined to a rather small region of excitation energy, angular momentum and parity. Several theoretical studies have shown that at low energies there is a dominance of one type of parity and near the particle separation energy that parity ratio only approaches to an equal distribution. An accurate determination of nuclear level density and its dependence on mass number, excitation energy, angular momentum, parity, etc. is necessary for precise prediction of cross sections using the statistical models. In the present work, an absolute asymmetry parameter is used to determine the level density of negative as well as for positive parity states by using s- and p- wave (D0 and D1) neutron level spacing. The systematic are investigated from 23 < A < 238 and compared to the pattern found in previous investigations. The present analysis also provides useful information on various resonance parameters at different nuclear mass regions with results that support the original conclusions.

Key-Words / Index Term :
Parity; Thermal and statistical models; Level density

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