LAMOST DR1 ve WASP’da bulunan düşük metal bolluklu zonklayan yıldızlar

Bu çalışmada “LAMOST Data Release 1 (DR1)” tayfsal veri tabanında yer alan düşük metal bolluklu zonklayan yıldızların incelemesi sunulmuştur. Çalışmada kullanılan sistemler LAMOST DR1 veritabanında yer alan ve metal bolluğu -2.4 ile -0.5 dex, etkin sıcaklığı 6500 ile 8600 K ve yüzey çekim ivmesi log g = 3.8 – 4.5 cgs aralığında bulunan yıldızlardan seçilmiştir. Seçilen yıldızların fotometrik verileri WASP veritabanından alınmıştır. Fotometrik veriler kullanılarak ışık değişimi gösteren yıldızlar belirlenmiş ve değişim frekansları elde edilmiştir. Sonuç olarak analiz edilen sistemlerden beşi kesin, ikisi aday RR Lyrae ve üçü de aday SX Phoenix yıldızı olarak tanımlanmıştır. Ayrıca, yıldızların tayf türleri, etkin sıcaklık değerleri ve dönme hızları tayfsal verilerin analiziyle tayin edilmiştir.

Low-metallicity pulsating stars in the LAMOST DR1 and WASP

In this study, the results of a research about low-metallicity pulsating stars are presented. The stars having metallicity from -2.4 to -0.5 dex were selected from the LAMOST DR1 catalogue considering the ranges of 6500-8600 K, 3.8-4.5 cgs of effective temperature and surface gravity, respectively. Photometric data of the selected stars were taken from the WASP. The stars showing light variation were determined and variability frequencies of the stars were derived. As a result, five confirmed, two candidate RR Lyrae stars and three suspect SX Phoenix variables were found. Additionally, spectral types, effective temperatures, and projected rotational velocities of the stars were derived.

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