THE STUDY OF THE DEPENDENCE OF THE BETA DECAY RATES IN R-PROCESS NUCLEI ON MASS NUMBER (A) BY PYATOV METHOD

Yıl 2010, Sayı: 022, 1 - 8, 15.08.2010

Tahsin Babacan Bünyamin Özaydın Semiha Cınar Yüksel Karabulut Kaan Manisa Cevat Selam Abdulkadir Yörük

Öz

In
this study,  the dependence of the beta
decay rates in r-process nuclei on mass number has been investigated by using
Pyatov Method within the framework of the quasi-particle Random Phase
Approzimation(QRPA). In this respect, first of all, half lives for have been
calculated for ^68-78Ni isotopes lying around N=50, Z= 28 region and
in the mass region of A=60-90. Then, the variation  of the calculated half lives with respect to mass
number has been investigated and compared with the available experimental
results.It has been seen that our calculation results obtained for regions
mentioned above  are not so far from the
experimental results.Moreover, in order to see whether Pyatov method is
successful or not in explaining the half lives of nuclei in different regions,
half lives for ^124-132Cd isotopes near N=82, Z=50 region have also
been calculated in additon to the above calculations, and compared with the
corresponding experimental values. 

Anahtar Kelimeler

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

PYATOV YÖNTEMİYLE R SÜRECİ ÇEKİRDEKLERDE BETA BOZUNUM HIZLARININ KÜTLE NUMARASINA (A) BAĞLILIĞININ İNCELENMESİ

Öz

Bu
çalışmada, Pyatov yöntemi kullanılarak R süreci çekirdeklerde beta bozunum
hızlarının kütle numarasına olan bağlılığı kuazi parçacık rastgele faz yaklaşımı
(QRPA) çerçevesinde incelendi ve öncelikle A=60-90 bölgesinde ve N=50, Z=28
yakınlarında yer alan ^68-78Ni izotopları için yarı ömür değerleri
hesaplandı. Daha sonra bu değerlerin kütle numarasına göre değişimleri
incelendi ve mevcut deneysel sonuçlarla karşılaştırıldı. Yukarıda bahsettiğimiz
bölgeler için elde edilen sonuçlarımızın deneysel değerlerden çok da uzak
olmadığı görüldü. Ayrıca, Pyatov yönteminin farklı bölgelerdeki çekirdeklerde
yarı ömür değerlerini açıklamada ne kadar başarılı olduğunu görmek amacıyla
yukarıda bahsettiğimiz hesaplara ek olarak, N=82, Z=50 bölgesi civarındaki ^124-132Cd
izotopları için de yarı ömür değerleri hesaplandı ve sonuçlarımız deneysel
değerlerle karşılaştırıldı.

Anahtar Kelimeler

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

Kaynakça

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