Radio follow-up of the γ-ray flaring gravitational lens JVAS B0218+357
Loading...
Files
Links to Files
Author/Creator ORCID
Date
2016-02-10
Type of Work
Department
Program
Citation of Original Publication
C. Spingola, D. Dallacasa, M. Orienti, M. Giroletti, J. P. McKean, C. C. Cheung, T. Hovatta, S. Ciprini, F. D'Ammando, E. Falco, S. Larsson, W. Max-Moerbeck, R. Ojha, A. C. S. Readhead, J. L. Richards, J. Scargle, Radio follow-up of the γ-ray flaring gravitational lens JVAS B0218+357, Monthly Notices of the Royal Astronomical Society, Volume 457, Issue 2, 01 April 2016, Pages 2263–2271, https://doi.org/10.1093/mnras/stw136
Rights
This item is likely protected under Title 17 of the U.S. Copyright Law. Unless on a Creative Commons license, for uses protected by Copyright Law, contact the copyright holder or the author.
Public Domain Mark 1.0
This work was written as part of one of the author's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law
Public Domain Mark 1.0
This work was written as part of one of the author's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law
Subjects
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 γ-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 γ-ray variability is located in the core of the active galactic nuclei, which is opaque up to the highest observing frequency of 22 GHz.