Potansiyel Bir SPB Yıldızı Olan η Tau Yıldızının Frekans Analizi

Bu çalışmada, η Tau yıldızının 2007 ile 2011 yılları arasında STEREO uydusundan alınan beş yıllık fotometrik verileri sunulmaktadır. Yüksek duyarlılığa sahip veriler, yıldızdaki Be olgusunu daha iyi anlamak için tayfsal bulgulardan elde edilen sonuçlarla karşılaştırılmıştır. Tayfsal veriler fotometrik gözlemlerle aynı zaman aralığını kapsamaktadır. η Tau, tayflarında çift pikli Hα salma profili göstermektedir. Bu profili analiz etmek için, Hα salma çizgileri, eşdeğer genişlikleri ve çizgi şiddetleri ölçülerek incelenmiştir. Fotometrik ve spektroskopik analizler sonucunda, yıldızın frekans dağılımı ve genlik şiddetlerinin tipik bir Be yıldızından farklı olduğu ortaya çıkmıştır. Sıcaklık ve parlaklık değerleri gibi fiziksel parametrelerine dayanarak yıldızın Yavaş Zonklayan B tipi bir emisyon yıldızı olduğu sonucuna varılabilir. Öte yandan, emisyon çizgilerinin eşdeğer genişlik değerleri, salınım frekansları ve genlikleri ile ilişkili görünmektedir. Bu da, fotometrik değişimlerin çevresel disk yapısıyla ilişkili olabileceğini göstermektedirDoğuş ÖZUYAR, dozuyar@ankara.edu.tr, ORCID: https://orcid.org/ 0000-0001-8544-0950

Anahtar Kelimeler:

η Tau, Emisyon çizgisi, Be yıldızları, Veri analizi, STEREO uydusu

Frequency Analysis of a Potential SPB Star η Tau

In this study, five years of photometric data of η Tau obtained from the STEREO satellite between 2007 and 2011 are presented. The high-precision data are compared with the results derived from the spectroscopic findings to gain a better understanding of the Be phenomenon in the star. The spectroscopic data cover the same time interval as the photometric observations. η Tau displays a double peaked Hα emission profile in its spectra. In order to analyze this profile, the Hα emission lines are examined by measuring their equivalent widths and line intensities. As a result of the photometric and spectroscopic analyses, it is revealed that the frequency distribution and amplitude intensities of the star are different from those of a typical Be star. Based on its physical parameters such as temperature and luminosity values, it may be conclude that the star is a Slowly Pulsating B type emission star. On the other hand, the equivalent width values of the emission lines appear to be related to the oscillation frequencies and their amplitudes. This indicates that the photometric variations may be related to the environmental disc structure.Doğuş ÖZUYAR, dozuyar@ankara.edu.tr, ORCID: https://orcid.org/ 0000-0001-8544-0950

Keywords:

η Tau, Emission line, Be stars, Data analysis, STEREO satellite,

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