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

Year 2010, Issue: 022, 33 - 40, 15.08.2010

Tahsin Babacan Kaan Manisa Yüksel Karabulut Cevat Selam Abdülkadir Yörür

Abstract

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. 

Keywords

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

Abstract

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.

Keywords

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

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