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A search for sub-second radio variability predicted to arise toward 3c 84 from intergalactic dispersion

Lookup NU author(s): Dr Christopher Hales



This is the authors' accepted manuscript of an article that has been published in its final definitive form by Institute of Physics Publishing, 2016.

For re-use rights please refer to the publisher's terms and conditions.


© 2016. The American Astronomical Society. All rights reserved.We empirically evaluate the scheme proposed by Lieu & Duan in which the light curve of a time-steady radio source is predicted to exhibit increased variability on a characteristic timescale set by the sightline's electron column density. Application to extragalactic sources is of significant appeal, as it would enable a unique and reliable probe of cosmic baryons. We examine temporal power spectra for 3C 84, observed at 1.7 GHz with the Karl G. Jansky Very Large Array and the Robert C. Byrd Green Bank Telescope. These data constrain the ratio between standard deviation and mean intensity for 3C 84 to less than 0.05% at temporal frequencies ranging between 0.1 and 200 Hz. This limit is 3 orders of magnitude below the variability predicted by Lieu & Duan and is in accord with theoretical arguments presented by Hirata & McQuinn rebutting electron density dependence. We identify other spectral features in the data consistent with the slow solar wind, a coronal mass ejection, and the ionosphere.

Publication metadata

Author(s): Hales CA, Max-Moerbeck W, Roshi DA, Rupen MP

Publication type: Article

Publication status: Published

Journal: Astrophysical Journal

Year: 2016

Volume: 823

Issue: 2

Online publication date: 25/05/2016

Acceptance date: 10/04/2016

Date deposited: 30/06/2017

ISSN (print): 0004-637X

ISSN (electronic): 1538-4357

Publisher: Institute of Physics Publishing


DOI: 10.3847/0004-637X/823/2/93


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