Tuncay BAYRAM, Serkan AKKOYUN, Yasemin AYHAN

Ca İzotopları için Nükleer Kabuk Modeli Hesaplamaları

Nükleer uyarılmış durum enerjileri, nükleer enerji/parite ve nükleer seviyeler arasındaki geçiş olasılıkları nükleer kabuk modeli kapsamında teorik olarak hesaplanabilir. Sihirli sayıları olan çekirdekler, hesaplamalarda kor çekirdek olarak kullanılır. Kor çekirdekteki nükleonların çekirdek dışına çıkmadığı varsayılmaktadır. Kabuk modeli hesaplamalarında sadece değerlik nükleonları dikkate alınır. Bu çalışmada, çift-çift 42-56Ca izotoplarının enerji seviyeleri, KShell bilgisayar kodu kullanılarak nükleer kabuk modeli kapsamında hesaplanmıştır. Bu kod, M şema gösterimi ile nükleer kabuk modeli hesaplamaları yapmaya olanak sağlar. Hesaplamalarda, çift sihirli 40Ca izotopu kor çekirdek olarak alındı. Nötronlar için 0f7/2,1p3/2, 0f5/2 and 1p1/2 yörüngeleri model uzay olarak kabul edildi. Ca izotopları için uyarılmış nükleer seviye spinleri, pariteleri ve enerjileri elde edildi. Sonuçlar literatürdeki mevcut deneysel değerlerle karşılaştırıldı.

Nuclear Shell Model Calculations for Ca Isotopes

Energies of nuclear excited states of nuclei, nuclear spin/parity and transition probabilities between nuclear levelscan be calculated in the scope of nuclear shell model. The nuclei having magic numbers are used as inert core inthe calculations. It is assumed that the nucleons in the inert core do not move outside from the core. Only valancenucleons out of the core are considered in the shell model calculations. In this study, the nuclear energy levels ofeven-even 42-56Ca isotopes have been calculated by the nuclear shell model using KShell computer code. This codeenables us to perform nuclear shell-model calculations with M-scheme representation. In the calculations, doublymagic 40Ca isotope was taken as core. For the neutrons, 0f7/2, 1p3/2, 0f5/2 and 1p1/2 orbits are considered as modelspace. Excited nuclear level spins, parities and energies have been obtained for Ca isotopes. The results have beencompared with the available experimental values in the literature.

PDF

___

[1] Mayer M.G. 1949. On Closed Shells in Nuclei. II. Phys. Rev., 75: 1969.
[2] Haxel O., Hans J., Jensen D., Suess H.E. 1949. On the "Magic Numbers" in Nuclear Structure. Phys. Rev., 75: 1766.
[3] Mayer M.G. 1948. On Closed Shells in Nuclei. Phys. Rev., 74: 235.
[4] Mayer M.G. 1950. Nuclear Configurations in the Spin-Orbit Coupling Model. I. Empirical Evidence. Phys. Rev., 78: 16.
[5] Talmi I. 2005. 55 years of the shell model: a challenge to nuclear many-body theory. Int. J. Mod. Phys. E, 14: 821.
[6] Caurier E., Martinez-Pinedo G., Nowacki F., Poves A., Zuker A.P. 2005. The shell model as a unified view of nuclear structure. Rev. Mod. Phy., 77: 427.
[7] Brown B.A. 2001. The Nuclear Shell Model Towards the Drip Lines. Prog. Part. Nucl. Phys. 47: 517.
[8] Mitler H.E. 1961. Shell-Model Analysis of Calcium Isotopes. Nucl. Phys., 23: 200.
[9] Engeland T., Osnes E. 1966. Shell Model Calculations in the Calcium Isotopes. Phys. Lett., 20: 424.
[10] Bhoy B., Srivastava P.C., Kaneko K. 2020. Shell model results for 47–58Ca isotopes in the fp, fpg9/2 and fpg9/2d5/2 model spaces. Journal of Physics G: Nuclear and Particle Physics, 47: 065105.
[11] Hussain F.M., Khudhur M. 2013. Shell Model Calculations for Even-Even 42,44,46Ca Nuclei. Journal of Information Engineering and Applications, 3: 46.
[12] Shimizu N. 2013. Nuclear shell-model code for massive parallel computation. KSHELL, arXiv:1310.5431 [nucl-th].
[13] Akkoyun S., Bayram T., Böyükata M. 2019. Shell Model Calculations for some pf Shell Nuclei. ALKÜ, NSP2018 Special Issue, 18.
[14] Akkoyun S., Bayram T. 2019. Shell Model Calculations for Proton-rich Zn Isotopes via New Generated Effective Interaction by Artificial Neural Networks. Cumhuriyet Sci. J., 40: 570.
[15] Brown B.A., Rae W.D.M. 2014. The Shell-Model Code NuShellX@MSU. Nucl. Data Sheets, 120: 115.
[16] REDSTICK, http://www.phys.lsu.edu/faculty/cjohnson/redstick.html. (Access date: 01.10.2019).
[17] Jhonson C.W., Ormand W.E., McElvain K.S., Shan H. 2018. BIGSTICK: A flexible configuration-interaction shell-model code. arXiv:1801.08432v1 [physics.comp-ph].
[18] ANTOINE, http://www.iphc.cnrs.fr/nutheo/code_antoine/menu.html (Access date: 01.10.2019).
[19] Brown B.A., Oxbash for Windows, MSU_NSCL report number 1289.
[20] Kinsey, R.R., Dunford C.L., Tuli J.K. Burrows T.W. 2019. The NUDAT/PCNUDAT Program for Nuclear Data, paper submitted to the 9th International Symposium of Capture Gamma-Ray Spectroscopy and Related Topics, Budapest, Hungary, October 1996. Data extracted from the NUDAT database, 2.8 (01.July.2019).