Multi-band optical variability of the blazar OP 313 in the outburst state during 2024-2025

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Devanand, P. U., Gupta, Alok C., Dogra, Karan, Kishore, Shubham, Tripathi, Tushar
Formato: Preprint
Publicado: 2025
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866908529538891776
author Devanand, P. U.
Gupta, Alok C.
Dogra, Karan
Kishore, Shubham
Tripathi, Tushar
author_facet Devanand, P. U.
Gupta, Alok C.
Dogra, Karan
Kishore, Shubham
Tripathi, Tushar
contents We present the analysis results of flux and spectral variability of the blazar OP 313 across intra-night to short-term timescales using BVRI photometric data, gathered over 25 nights from Nov 2024 to May 2025, using two optical telescopes in ARIES, India. The source was in an outburst state during this period. We searched for intraday variations (IDV), using two powerful statistical tests: the Power Enhanced F-test and the Nested ANOVA test. The source displayed IDV in the R band for five of the ten nights, yielding a duty cycle of 34$\%$. During the entire monitoring of the source, it showed variations of over two mag in all B, V, R, and I data bands. We obtained a variability timescale for a variable light curve, giving us an upper limit for the size of the emission region. We generated optical SEDs of the blazar for these 25 nights, fitted a power law of form $(F_ν\propto ν^{-α_{o}})$ and found the weighted mean spectral index to be 1.471$\pm$0.004. An analysis of the color-magnitude diagram shows that, contrary to the redder-when-brighter (RWB) trend typically observed in FSRQs, this source exhibits a bluer-when-brighter (BWB) trend on short-term variability (STV) timescales - a behavior more commonly associated with BL Lac object. We explore potential physical mechanisms responsible for the observed spectral variability.
format Preprint
id arxiv_https___arxiv_org_abs_2507_20223
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Multi-band optical variability of the blazar OP 313 in the outburst state during 2024-2025
Devanand, P. U.
Gupta, Alok C.
Dogra, Karan
Kishore, Shubham
Tripathi, Tushar
High Energy Astrophysical Phenomena
We present the analysis results of flux and spectral variability of the blazar OP 313 across intra-night to short-term timescales using BVRI photometric data, gathered over 25 nights from Nov 2024 to May 2025, using two optical telescopes in ARIES, India. The source was in an outburst state during this period. We searched for intraday variations (IDV), using two powerful statistical tests: the Power Enhanced F-test and the Nested ANOVA test. The source displayed IDV in the R band for five of the ten nights, yielding a duty cycle of 34$\%$. During the entire monitoring of the source, it showed variations of over two mag in all B, V, R, and I data bands. We obtained a variability timescale for a variable light curve, giving us an upper limit for the size of the emission region. We generated optical SEDs of the blazar for these 25 nights, fitted a power law of form $(F_ν\propto ν^{-α_{o}})$ and found the weighted mean spectral index to be 1.471$\pm$0.004. An analysis of the color-magnitude diagram shows that, contrary to the redder-when-brighter (RWB) trend typically observed in FSRQs, this source exhibits a bluer-when-brighter (BWB) trend on short-term variability (STV) timescales - a behavior more commonly associated with BL Lac object. We explore potential physical mechanisms responsible for the observed spectral variability.
title Multi-band optical variability of the blazar OP 313 in the outburst state during 2024-2025
topic High Energy Astrophysical Phenomena
url https://arxiv.org/abs/2507.20223