Short-Term Variability of Hα Emission Line Parameters in π Aqr as a Be Star

Authors

  • Taufieq Zannata Ramadhan Astronomy Study Program, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesa No. 10, Bandung, 40132, Indonesia
  • Aprilia Astronomy Research Group, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesa No. 10, Bandung, 40132, Indonesia

DOI:

https://doi.org/10.21009/SPEKTRA.103.02

Keywords:

Be star, π Aqr, spectrum variability, line parameter, circumstellar disk

Abstract

B-emission (Be) star is a B type star which shows emission line in its spectrum, especially Hα, caused by the disk surrounding it. One of the Be stars, π Aqr, is a binary Be star in constellation Aquarius which shows variability of double-peaked Hα emission line caused by a circumstellar disk around the primary component. We aim to study recent physical phenomenon which occurs in the disk of π Aqr star based on its spectral data from 2004 to 2024, retrieved from BeSS database, by analyzing the variability of its Hα emission line parameters: the Violet-to-Red peak ratio (V/R), Emission-to-Continuum ratio (E/C), Equivalent Width (EW), Full Width at Half Maximum (FWHM), and peak separation. The variation of V/R ratio from 2004 to 2019 shows period of 84.1 days which corresponds with orbital period of the binary system. However, in 2024, the V/R variability does not show similar cycle period in previous years as the red peak strength dominates throughout most of the year. The EW and E/C increase, indicating rising disk activity and expansion until 2024. Overall increase of red and blue peak separation roughly suggests expansion in Hα region in the disk.

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Published

2025-12-19

How to Cite

Ramadhan, T. Z., & Aprilia. (2025). Short-Term Variability of Hα Emission Line Parameters in π Aqr as a Be Star. Spektra: Jurnal Fisika Dan Aplikasinya, 10(3), 165–176. https://doi.org/10.21009/SPEKTRA.103.02

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Vol. 10 No. 3 (2025): SPEKTRA: Jurnal Fisika dan Aplikasinya, Volume 10 Issue 3, December 2025

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Copyright (c) 2025 Taufieq Zannata Ramadhan, Aprilia

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