Effect of Intrinsic Brightness Variations of Stars on Transit: An Analysis of WASP-19 and WASP-33 Systems

Abstract

This study involves an analysis of the TESS light curves of the WASP-19 and WASP-33 systems. While the host star in the WASP-19 system exhibits solar-like activity, the host star in the WASP-33 system pulsates. Both systems contain one transiting exoplanet. The research aims to examine the potential effects of intrinsic brightness variations in host stars on the analysis of transit light curves for these exoplanets. Light curves were analyzed both in their original form and after removing the intrinsic brightness variations of the host stars. The analyses concluded that the intrinsic brightness variations of the host stars in both systems do not significantly affect the determination of exoplanetary parameters through light curve modeling. However, this conclusion does not apply if the host star's intrinsic brightness variation exceeds the transit depth.

Keywords

• Exoplanets
• Stars: activity
• Stars: oscillations
• Techniques: photometric
• Methods: data analysis
• Astronomical data bases: TESS

Yıldızların Bünyesel Parlaklık Değişimlerinin Örtme Olayı Üzerindeki Etkisi: WASP-19 ve WASP-33 Sistemleri Üzerine Bir Analiz

Abstract

Bu çalışma, WASP-19 ve WASP-33 sistemlerinin TESS ışık eğrilerinin bir analizini içermektedir. WASP-19 sistemindeki barınak yıldız Güneş benzeri aktivite gösterirken, WASP-33 sistemindeki barınak yıldız zonklama yapmaktadır. Her iki sistemde de transit geçiş yapan birer ötegezegen bulunur. Bu araştırma kapsamında, barınak yıldızları bünyesel parlaklık değişimi gösteren ötegezegenlerin transit ışık eğrisi analizinde ne tür etkilerle karşılaşılabileceğinin bir incelemesi amaçlanmıştır. Işık eğrileri, hem orijinal haliyle hem de barınak yıldızın bünyesel parlaklık değişimlerinden arındırılmış haliyle analiz edilmiştir. Yapılan analizler her iki sistemdeki barınak yıldızın bünyesel parlaklık değişimlerinin ötegezegene ilişkin parametrelerin ışık eğrisi modellemesi ile hesaplanmasında önemli bir etkisi olmadığı sonucuna varılmıştır. Ancak bu sonuç barınak yıldızın transit derinliğinden daha derin bünyesel parlaklık değişimi göstermesi durumunda geçerli değildir.

Keywords

• Ötegezegenler
• Yıldızlar: aktivite
• Yıldızlar: salınım
• Teknikler: fotometrik
• Metotlar: veri analizi
• Astronomik veri tabanları: TESS

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