Ratio of level densities with opposite parities in 74Ge with considering the soft phase transition around critical temperature

Document Type : Full length research Paper

Authors

1 Department of Physics, Payame Noor University, Tehran, Iran

2 Physics Department, Faculty of Science, Imam Hossein Comprehensive University, Tehran, Iran

3 Joint Institute for Nuclear Research, Dubna, Russia

Abstract

Ratio of level densities with opposite parities in 74Ge with considering the soft phase transition around critical temperature
In this study , the ratio of nuclear level densities with opposite parities was studied for 74Ge using the generalized, superfluid theory in many - body systems with considering a soft phase transition around the critical temperature. With modified gap parameter, the ratio of nuclear level densities in the form of a smooth function tends to unity with increasing energy . Phase transition occurs at T ≈ 1.1 MeV and at higher energies the approximation of equal parity distribution is applicable .

Keywords

Main Subjects

References

[1] R. Razavi, A. Rahmatinejad, T. Kakavand, F. Taheri, M. Aghajani, A. Khooy, Studying Nuclear Level Densities of 238U in the Nuclear Reactions within the Macroscopic Nuclear Models, Zeitschrift für Naturforschung A 71 2 (2016) 157-160.
https://doi.org/10.1515/zna-2015-0339
[2] R. Razavi, A. Rahmatinejad, T. Kakavand, A. Khooy, Pairing phase transition of nucleons in 89Y and 208Pb, journal of research on many body systems 7 1300435 (2017) 79-85.
https://doi.org/10.22055/jrmbs.2017.13016
[3] S. Rasouli, A.N. Behkami, R. Razavi, A.A. Sabouri Dodaran, M.R. Bayati, Investigation on Neutron-Induced Fission Fragment Angular Distribution of 232Th and 238U, Zeitschrift für Naturforschung A 73 11 (2018) 1075-1081.
https://doi.org/10.1515/zna-2018-0267
[4] A.J. Koning, S. Hilaire, S. Goriely, Global and local level density models, Nuclear Physics A 810 1-4 (2008) 13-76.
https://doi.org/10.1016/j.nuclphysa.2008.06.005
[5] H.A. Bethe, An Attempt to Calculate the Number of Energy Levels of a Heavy Nucleus, Physical Review 50 4 (1936) 332.
https://doi.org/10.1103/PhysRev.50.332
[6] L.G. Moretto, Thermodynamical properties of a paired nucleus with a fixed number of quasi-particles. Nuclear Physics A 243 1 (1975) 77-99.
https://doi.org/10.1016/0375-9474(75)90022-6
[7] R. Razavi, A. Rashed Mohassel, A. Rahmatinejad, A. jabarpour, Systematic of critical temperature of nuclear pairing transition, Nuclear Physics A. 976 61 (2018) 61-69.
https://doi.org/10.1016/j.nuclphysa.2018.05.001  
[8] A. Rahmatinejad, R. Razavi,T. Kakavand, Thermal quantities of 46Ti, Nuclear Physics A 939 46 (2015) 46-52.
https://doi.org/10.1016/j.nuclphysa.2015.03.010
[9] R. Razavi, A.N. Behkami, S. Mohammadi, Microscopic study of nuclear level densities and thermodynamical properties in 170,171,172 Yb, Physica Scripta, 86 4 (2012) 045201.
https://doi.org/10.1088/0031-8949/86/04/045201
[10] R. Razavi, Role of neutrons and protons in entropy, spin cut off parameters, and moments of inertia, Physical Review C 88 (2013) 014316.
https://doi.org/10.1103/PhysRevC.88.014316
[11] R. Razavi, T. Kakavand, Level studies of 93Mo via 93Nb (p, nγ) 93Mo reaction and density of discrete levels in 93Mo, Nuclear Technology and Radiation Protection 26 1 (2012) 69-73.
https://doi.org/10.2298/NTRP1101069R
[12] N. Cerf, Parity Dependence of the Nuclear Level Density, Nuclear Physics A 554 (1993) 85-106.
https://doi.org/10.1016/0375-9474(93)90359-6
[13] B.V. Rao, H.M. Agrawal, Parity Dependence of the Nuclear Level Density at High Excitation, Nuclear Physics A 592 (1995) 1-8.
https://doi.org/10.1016/0375-9474(95)00165-W
[14] A. Rahmatinejad, R. Razavi, T. Kakavand, Role of neutron and proton system in spin cut off parameter and entropy of 89, 90Y, Nuclear Physics A Vol 941 (2015) 145-151.
https://doi.org/10.1016/j.nuclphysa.2015.06.013
[15] J. Bardeen, L.N. Cooper, J.R. Schrieffer, Theory of superconductivity, Physical Review 108 (1957) 1175.
https://doi.org/10.1103/PhysRev.108.1175
[16] R. Razavi, et al., Ratio of neutron and proton entropy excess in 121Sn compared to 122Sn, Physical Review C 86 (2012) 047303.
https://doi.org/10.1103/PhysRevC.86.047303
[17] D. Mocelj et al., Parity-Dependence in the Nuclear Level Density, Nuclear Physics A 758 (2005) 154c–157c.
https://doi.org/10.1016/j.nuclphysa.2005.05.032
[18] A.N. Behkami, J.R. Huizenga, Comparison Of Experimental Level Densities and Spin Cut Off factors with Microscopic Theory For Nuclei Near A= 60, Nuclear Physics A 217 (1973) 78-92.
https://doi.org/10.1016/0375-9474(73)90624-6  
[19] A. Rahmatinejad, R. Razavi, T. Kakavand, Temperature dependent pairing gap in nucle, International Journal of Modern Physics E 27 01 (2018) 1850003.
https://doi.org/10.1142/S0218301318500039
[20] D. Mocelj et al., Large-scale prediction of the parity distribution in the nuclear level density and application to astrophysical reaction rates, Phys. Rev. C 75 (2007) 045805.
https://doi.org/10.1103/PhysRevC.75.045805
[21] Y. Alhassid, G.F. Bertsch, S. Liu and H. Nakada, Parity Dependence of Nuclear Level Densities, Physical Review Letter 84 19 (2000) 4313- 4316.
https://doi.org/10.1103/PhysRevLett.84.4313  
[22] A. Rahmatinejad, R. Razavi and T. Kakavand, Studying temperature dependence of pairing gap parameter in a nucleus as a small superconducting system, International Journal of Modern Physics E 25 (2016) 1650050.
https://doi.org/10.1142/S0218301316500506
[23] T. Renstrom, et al., Low-energy enhancement in the γ-ray strength functions of 73,74Ge, Physical Review C 93 (2016) 064302.
https://doi.org/10.1103/PhysRevC.93.064302
[24] R. Razavi, O. Nouri, A. Rahmatinejad, S. Mohammadi, Parity equilibration in nuclear level densities of 159–166Dy, Modern Physics Letters A 35. 38 (2020) 2050315.
https://doi.org/10.1142/S0217732320503150
Journal of Research on Many-body Systems
Volume 11, Issue 2 - Serial Number 29
September 2021
Pages 45-54

Files

History

  • Receive Date: 14 May 2020
  • Revise Date: 15 May 2021
  • Accept Date: 04 August 2021

Share

How to cite

Statistics