RR Lyrae stars with variable mean magnitudes
Year: 2026
Type: article
Abstract: Context. A number of RR Lyrae stars exhibit variable mean magnitudes in the OGLE survey light curves of the Galactic bulge. Hitherto, this phenomenon has not been studied, as it was generally assumed to be related to photometric issues. Aims. We investigate whether the mean magnitude variability of RR Lyrae variables is due to genuine astrophysical phenomena. Methods. We used the extended, and in many cases overlapping, light curves from multiple microlensing surveys to study RR Lyrae stars with apparent mean-magnitude variations. A modified Fourier-series based fitting method is introduced to analyze the light curves showing mean-magnitude variations. Data from infrared surveys were also used to construct spectral energy distributions (SEDs). Results. Presented here are 72 stars where the mean-magnitude variations are most probably of genuine astrophysical origin, rather than the result of photometric problems. The ratio of variation between the V and I bands is compatible with variable extinction by dust in most cases, but no infrared excess is detected in the SEDs. The occurrence rate of the phenomenon, after correcting for selection effects, is ∼0.9% among RR Lyrae variables in the OGLE bulge fields.
Source: Astronomy and Astrophysics
Institutions: Nicolaus Copernicus Astronomical Center, Konkoly Observatory, HUN-REN Research Centre for Astronomy and Earth Sciences, Pontificia Universidad Católica de Chile, Millennium Institute of Astrophysics, University of Concepción, University of Warsaw, Korea Astronomy and Space Science Institute
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,865
Funders: National Science Foundation, U.S. Department of Energy, National Aeronautics and Space Administration, California Institute of Technology, University of Canterbury, European Commission, Royal Society Te Apārangi, Korea Astronomy and Space Science Institute, Narodowe Centrum Nauki, Narodowym Centrum Nauki, Agencia Nacional de Investigación y Desarrollo, Korea Research Environment Open Network, Horizon 2020 Framework Programme, Japan Society for the Promotion of Science, Marsden Fund, Agencia Estatal de Investigación, Lawrence Livermore National Laboratory
Awards: G1101028137, G1175115578, INSTITUTO MILENIO DE ASTROFISICA, G1702950523, G2060178711, G210041235, G2262748287, G2428672771, G2530996747, G2601397997, G275860125, G2945112853, G300979063, G3177268909, G34346518, G3480869486, G3681454997, G4042783231, G425668148, G434337789, G4534730369, G4538171546, G5061205453, G5080475149, Center for Particle Astrophysics, G5195188938, G5498856803, G57481727, G5834573078, G6445123630, STELLAR ASTROPHYSICS IN THE GAIA-LSST ERA, G6584649838, G7084143925, G722162065, G7579287858, 古代説話における諸寺縁起の研究, CENTRO DE ASTROFISICA Y TECNOLOGIAS AFINES (CATA)
OpenAlex ID: W7123345975