Radio follow-up of the gamma-ray flaring gravitational lens JVAS B0218+357

Spingola, C.; Dallacasa, D.; Orienti, M.; Giroletti, M.; McKean, J. P.; Cheung, C. C.; Hovatta, T.; Ciprini, S.; D'Ammando, F.; Falco, E.; Larsson, S.; Max-Moerbeck, W.; Ojha, R.; Readhead, A. C. S.; Richards, J. L.; et. al.

Abstract

We present results on multifrequency Very Long Baseline Array (VLBA) monitoring observations of the double-image gravitationally lensed blazar JVAS B0218+357. Multi-epoch observations started less than one month after the gamma-ray flare detected in 2012 by the Large Area Telescope on board Fermi, and spanned a 2-month interval. The radio light curves did not reveal any significant flux density variability, suggesting that no clear correlation between the high-energy and low-energy emission is present. This behaviour was confirmed also by the long-term Owens Valley Radio Observatory monitoring data at 15 GHz. The milliarcsecond-scale resolution provided by the VLBA observations allowed us to resolve the two images of the lensed blazar, which have a core-jet structure. No significant morphological variation is found by the analysis of the multi-epoch data, suggesting that the region responsible for the gamma-ray variability is located in the core of the active galactic nuclei, which is opaque up to the highest observing frequency of 22 GHz.

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Título según WOS: ID WOS:000373580500086 Not found in local WOS DB
Título de la Revista: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
Volumen: 457
Número: 2
Editorial: OXFORD UNIV PRESS
Fecha de publicación: 2016
Página de inicio: 2263
Página final: 2271
DOI:

10.1093/mnras/stw136

Notas: ISI