R SÜRECİ ÇEKİRDEKLERDE BETA BOZUNUM YARI ÖMÜRLERİNİN NÖTRON SAYISINA(N) BAĞLILIĞININ PYATOV YÖNTEMİYLE İNCELENMESİ

Öz

Bu çalışmada, Pyatov yöntemi kullanılarak Kuaziparçacık Rastgele Faz Yaklaşımı (QRPA) çerçevesinde r-süreci çekirdeklerde beta bozunum yarı ömürlerinin nötron sayısına bağlılığı incelendi. Bu bağlamda, N=50 bölgesi civarındaki ^74-80Zn izotoplarına ait beta bozunum yarı ömür değerleri hesaplandı. Hesaplanan bu değerlerin nötron sayısıyla olan değişiminin grafiği çizildi. Elde edilen sonuçlar, mevcut deneysel değerler ve diğer teorik çalışmalarla karşılaştırıldı. Hesaplamalarımız, deneysel değerlerden çok uzak olmamasına rağmen, diğer teorik çalışmalara göre yarı ömür değerlerinin küçük olduğunu göstermektedir. 

Anahtar Kelimeler

• R- süreci,beta bozunum hızı,Gamow-Teller geçişleri

THE STUDY OF THE DEPENDENCE OF THE BETA DECAY HALF LIVES IN R-PROCESS NUCLEI ON NEUTRON NUMBER (N) BY PYATOV METHOD

Öz

In this study, the dependence of the beta decay half lives in r-process nuclei on neutron  number has been investigated by using Pyatov Method within the framework of the quasi-particle Random Phase Approzimation(QRPA).  In this respect, beta decay half lives for ^74-80Zn isotopes near N=50 region have been calculated. The variation  of these calculated values with respect to neutron number has been plotted. The calculated  results have been compared with the experimental and other theoretical studies. Our calculation results has shown that although they are not so far from the experimental values,  calculated half life values are stil smaller compared to other theoretical studies.

Anahtar Kelimeler

• R-process,beta decay rate,Gamow-Teller transitions

Kaynakça

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