Amb motiu del tancament d'estiu, la validació de documents es reprendrà a partir del 28 d'agost de 2026. Disculpeu les molèsties.
Con motivo del cierre de verano, la validación de documentos se reanudará a partir del 28 de agosto de 2026. Disculpad las molestias
Due to the summer closure, document validation will resume starting August 28, 2026. We apologize for any inconvenience.

Files

657098.pdf (2.23 MB)

Document type

Article

Version

Published version

Publication date

2016-02-21

All rights reserved

Please use this identifier to cite or link to this item: https://hdl.handle.net/2445/113867

Orbital and superorbital variability of LS I +61 303 at low radio frequencies with GMRT and LOFAR

Journal Title

Authors

Director/Tutor

Journal ISSN

Volume Title

Related resource

https://doi.org/10.1093/mnras/stv2771

Abstract

LS I +61 303 is a gamma-ray binary that exhibits an outburst at GHz frequencies each orbital cycle of ≈26.5 d and a superorbital modulation with a period of ≈4.6 yr. We have performed a detailed study of the low-frequency radio emission of LS I +61 303 by analysing all the archival Giant Metrewave Radio Telescope data at 150, 235 and 610 MHz, and conducting regular LOw Frequency ARray observations within the Radio Sky Monitor (RSM) at 150 MHz. We have detected the source for the first time at 150 MHz, which is also the first detection of a gamma-ray binary at such a low frequency. We have obtained the light curves of the source at 150, 235 and 610 MHz, all of them showing orbital modulation. The light curves at 235 and 610 MHz also show the existence of superorbital variability. A comparison with contemporaneous 15-GHz data shows remarkable differences with these light curves. At 15 GHz we see clear outbursts, whereas at low frequencies we see variability with wide maxima. The light curve at 235 MHz seems to be anticorrelated with the one at 610 MHz, implying a shift of ∼0.5 orbital phases in the maxima. We model the shifts between the maxima at different frequencies as due to the expansion of a one-zone emitting region assuming either free-free absorption or synchrotron self-absorption with two different magnetic field dependences. We always obtain a subrelativistic expansion velocity, in some cases being close to the stellar wind one.

Subject

Raigs gamma, Estels binaris, Astrofísica

Subject (English)

Gamma rays, Double stars, Astrophysics

Citation

Collections

Articles publicats en revistes (Física Quàntica i Astrofísica)
Articles publicats en revistes (Institut de Ciències del Cosmos (ICCUB))

Citation

MARCOTE MARTIN, Benito, et al. Orbital and superorbital variability of LS I +61 303 at low radio frequencies with GMRT and LOFAR. Monthly Notices of the Royal Astronomical Society. 2016. Vol. 456, num. 2, pags. 1791-1802. ISSN 0035-8711. [consulted: 12 of August of 2026]. Available at: https://hdl.handle.net/2445/113867

Export metadata

JSON - METS

Share record