Üçlü alfa ve CNO reaksiyon oranlarının küçük kütleli yıldızların evrimi üzerindeki etkileri

Öz

Bu çalışmada, Üçlü Alfa ve CNO nükleer reaksiyonlarının enerji oluşum oranlarının 0.65- 1.2 Mʘ aralığında kütleye sahip olan Ana kol yıldız modellerinin evrimleri üzerindeki etkileri araştırılmaktadır. Her bir model için Paczynski’nin GOB, SCH ve HB7 yıldız model programları kullanılmaktadır. Yıldızların yaşları orjinal NACRE enerji oluşum oranları ve yüzde on oranında azaltılmış NACRE (Nuclear Astrophysics Compilation of Reactions) oranları kullanılarak hesaplanır. Buna göre IT Cas ve V636 Cen yıldızlarının yaşları hesaplanmıştır ve literatürdeki sonuçlar ile karşılaştırılmıştır. Üçlü Alfa reaksiyonlarının laboratuvar ortamında gerçekleştirilmesi çok zor olduğu için bu teorik model çalışmasının, küçük kütleli ve hatta büyük kütleli yıldızların gözlemsel çalışmalarına ışık tutacaktır.

Anahtar Kelimeler

• Nükleer enerji oluşum oranları
• küçük kütleli yıldızlar
• yıldızların evrimi

Effects of triple alpha and CNO reaction rates on the evolution of low- mass stars

Öz

In this study, the effects of the energy generation rates of Triple Alpha and CNO nuclear reactions on the evolution of Main sequence star models with masses in the range of 0.65-1.2 Mʘ are investigated. Paczynski's GOB, SCH and HB7 star model programs are used for each model. The ages of stars are calculated using the original NACRE (Nuclear Astrophysics Compilation of Reactions) energy generation rates and NACRE rates reduced by ten percent. The ages of the current IT Cas and V636 Cen stars are calculated and compared with the results in the literature. Since Triple Alpha reactions are very difficult to perform in terrestrial laboratories, this theoretical model study will shed light on observational studies of low-mass and even massive stars.

Anahtar Kelimeler

• Nuclear energy generation rates
• low mass stars
• stellar evolution

Kaynakça

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