Detection of stellar variability through S-PLUS project data

• Grant number: 21/10941-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2022
• End date: December 31, 2023
• Field of knowledge: Physical Sciences and Mathematics - Astronomy - Stellar Astrophysics
• Principal Investigator: Claudia Lucia Mendes de Oliveira
• Grantee: Liana Li
• Host Institution: Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

This project consists of a search for short-period stellar variability through data obtained in the context of the Southern Photometric Local Universe Survey (S-PLUS, Mendes de Oliveira et al. 2019), which is currently observing about a third of the hemisphere's sky south in 12 photometric bands distributed along the optical spectrum. The methodology involves exploring the cadence created by the S-PLUS observational strategy, whose images are sequentially obtained from 3 images for each of the 12 filters, allowing the analysis of the light curve for each star in the field using a Transform of Fourier (TF) in an attempt to detect a possible sign of variability. For this, two slightly different methods are used. The first consists of obtaining a normalized light curve for each individual band and the use of a TF for the entire curve, while the second involves the application of a TF for each band individually and the subsequent combination to obtain the probability of an indicative signal of variability. Currently, S-PLUS has already observed more than 2000 square degrees of the southern hemisphere sky, which increases the chances of discovering new variable stars, as well as the possibility of confirming the variability for objects classified as suspicious, which is of great interest. and importance to the astronomical community. Also, given that the observational strategy involves obtaining the spectral energy distribution of each star in 12 bands, at the end of the project it will be possible to obtain a first approximation of the probable spectral type of each object.(AU)