Revisiting the Period Change and Frequency Analysis of a Variable Star SZ Lyncis

Ronnakrit Rattanamala; Pornapa Artsang; Chanruangrit Channok; Thaweechai Chonsungnoen; Nutchanat Krinsungnoen; Pimmada Ngiabking; Phiyada Phumnok

doi:10.69650/ahstr.2024.2274

Authors

Ronnakrit Rattanamala Faculty of Science and Technology, Nakhon Ratchasima Rajabhat University, Nakhon Ratchasima, 30000, Thailand
Pornapa Artsang National Astronomical Research Institute of Thailand (Public Organization) 260 Moo 4, Donkaew, Maerim, Chiangmai, 50180 Thailand
Chanruangrit Channok Faculty of Science and Technology, Nakhon Ratchasima Rajabhat University, Nakhon Ratchasima, 30000, Thailand
Thaweechai Chonsungnoen Bachelor of Education Program in Physics, Nakhon Ratchasima Rajabhat University, Nakhon Ratchasima, 30000, Thailand
Nutchanat Krinsungnoen Bachelor of Education Program in Physics, Nakhon Ratchasima Rajabhat University, Nakhon Ratchasima, 30000, Thailand
Pimmada Ngiabking Bachelor of Education Program in Physics, Nakhon Ratchasima Rajabhat University, Nakhon Ratchasima, 30000, Thailand
Phiyada Phumnok Bachelor of Education Program in Physics, Nakhon Ratchasima Rajabhat University, Nakhon Ratchasima, 30000, Thailand

DOI:

https://doi.org/10.69650/ahstr.2024.2274

Keywords:

Variable star, Period change, SZ Lyncis

Abstract

This study aims to investigate the period change of the variable star SZ Lyncis. The observations were conducted at the Regional Observatory for the Public, Nakhon Ratchasima (ROP-NMA), operated by the National Astronomical Research Institute of Thailand (NARIT), on January 8^th-9^th and February 19^th-20^th 2024. The data was acquired using the CCD camera with a B-filter mount on the 0.7-m reflecting telescope. We report the period change of 1.37(±0.08)´10^-12 day cycle^-1. Analysis of the O-C diagram revealed the presence of a binary companion with a semi-amplitude of 0.0052(±0.0002) days, the projected semi-major axis of 0.90(±0.04) AU, the eccentricity of 0.25(±0.09), and the orbital period of 1184.1(±1.5) days and the mass function of 0.07(±0.01) M_⨀. We also identified the time-series light curve data using the Discrete Fourier transform (DFT) in the Period04 package and obtained results of four frequencies. The main frequency of 8.29630(±0.00002) cycle day^-1 corresponds to a period of 0.1205357(±0.0000003) days. These results contribute to our understanding of the pulsation properties of SZ Lyncis and its binary system.

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