LAMOST DR1 ve WASP'ta ki düşük metal bolluklu zonklayan yıldızlar

Year 2018, Volume: 22 Issue: 3, 938 - 944, 01.06.2018

Filiz Kahraman Aliçavuş

https://doi.org/10.16984/saufenbilder.341828

Abstract

 Bu çalışmada “LAMOST Data Release 1 (DR1)” tayfsal veri
tabanında yer alan düşük metal bolluklu zonklayan yıldızların incelemesi
sunulmuştur. Çalışmada kullanılan sistemler LAMOST DR1 katalogunda 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 aralığında
bulunan yıldızlardan seçilmiştir. Seçilen yıldızların fotometrik verileri ise
WASP katalogundan 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 hızlarıda
tayfsal verilerin analizi ile elde edilmiştir.

Keywords

Zonklayan yıldızlar, tayf analizi

Low-metallicity pulsating stars in the LAMOST DR1 and WASP

Abstract

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.

Keywords

Pulsating stars, Spectroscopic analysis, Atmospheric parameters

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