Potansiyel Bir SPB Yıldızı Olan η Tau Yıldızının Frekans Analizi

Year 2018, Volume: 13 Issue: 2, 72 - 82, 30.11.2018

Doğuş Özuyar

https://doi.org/10.29233/sdufeffd.440797

Abstract

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 göstermektedir

Doğuş ÖZUYAR, [e-mail],
ORCID: https://orcid.org/ 0000-0001-8544-0950

Keywords

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

Frequency Analysis of a Potential SPB Star η Tau

Abstract

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, [e-mail], ORCID: https://orcid.org/ 0000-0001-8544-0950

Keywords

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

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