Collective Nuclear Level Density Effect On Photonuclear Cross Section of 55Mn Isotope

Öz

The cross sections of (γ,n), (γ,2n) and (γ,3n) photonuclear reactions of 55Mn isotope were calculated by using TALYS 1.95 computer code from threshold energy to 37 MeV. Obtained theoretical results were compared with the experimental data. In the calculations, collective nuclear level density was included as an optional input in the computer code and the influence of the collective effects (rotational and vibrational) was investigated. As seen from the results, collective semi-classical nuclear level density model can be used as a reliable tool to calculate the cross sections of photonuclear reactions. Also, the effect of nuclear level density function which includes collective contributions was analyzed below 30 MeV gamma energy dominated by giant dipole resonance for these reactions.

Anahtar Kelimeler

• Photonuclear reaction,Cross section,Collective nuclear level density,TALYS

55Mn İzotopunun Fotonükleer Tesir Kesitleri Üzerinde Kollektif Nükleer Seviye Yoğunluğunun Etkisi

Öz

55Mn izotopunun (γ,n), (γ,2n) ve (γ,3n) fotonükleer reaksiyonlarının tesir kesitleri eşik enerjisinden 37 MeV'e kadar TALYS 1.95 bilgisayar kodu kullanılarak hesaplandı. Elde edilen teorik sonuçlar reaksiyonların deneysel verileri ile karşılaştırıldı. Hesaplamalarda, kollektif nükleer seviye yoğunluğu modeli (CSCFGM-Collective semi-classical Fermi gas model) bilgisayar programında opsiyonel bir girdi olarak dahil edildi ve kollektif etkilerin (rotasyonel ve vibrasyonel) fotonükleer tesir kesitleri üzerindeki etkisi araştırıldı. Sonuçlar incelendiğinde, kollektif yarı-klasik nükleer seviye yoğunluğu modelinin bu reaksiyonların tesir kesiti hesaplamalarında güvenilir bir araç olarak kullanılabileceği gösterildi. Ayrıca, dev dipol rezonansın baskın olduğu 30 MeV gama enerjisi altında gerçekleşen reaksiyonlarda kollektif katkıları içeren nükleer seviye yoğunluğu fonksiyonunun etkisi analiz edildi.

Anahtar Kelimeler

• Fotonükleer reaksiyon,Tesir kesiti,Kollektif nükleer seviye yoğunluğu,TALYS

Kaynakça

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