Optik Bölge Tayf Analizlerinden Manyetik Özellik Göstermeyen geç $B$ -- erken $F$ Türü Yıldızların Kimyasal Element Bollukları

Öz

Yıldızların ayrıntılı tayf analizleri yapılarak `normal', `civa--mangan (HgMn)' ve `metal ($Am$)' çizgi tayfları veren yıldız tiplerinin ayırt edici tayf çizgilerinden yola çıkılarak, bu yıldızların kimyası irdelendi. Ayrıca He, C, N, O elementleri yanında metallerin ve ağır metallerin yıldız atmosferlerindeki göreli bollukları, gözlemsel olarak türettiğimiz HR diyagramı üzerindeki dağılımları incelendi. Metal çizgili özel yıldızlarda tespit edilen element bolluk dağılımlarındaki değişimin, civa--mangan tipi yıldızlardakine nazaran daha az olduğu belirlendi. Civa--mangan tipinden soğuk yıldızların, metalik türden sıcak yıldızlar ile aynı evrim yolları üzerinde olduğu kanısına ulaşıldı.

Anahtar Kelimeler

• star: abundances
• stars: early-type
• spectroscopy

Kaynakça

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