@inbook{09f577f3990548118b6edce29eb0e751,
title = "On rapid interstellar scintillation of quasars: PKS 1257-326 revisited",
abstract = "The line of sight towards the compact, radio loud quasar PKS 1257-326 passes through a patch of scattering plasma in the local Galactic ISM that causes large and rapid, intra-hour variations in the received flux density at centimetre wavelengths. This rapid interstellar scintillation (SS) has been occurring for at least 15 years, implying that the scattering screen is at least 100 AU in physical extent. Through observations of the ISS we have measured microarcsecond-scale core shifts in PKS 1257-326, corresponding to changing opacity during an intrinsic outburst. Recent analysis of VLA data of a sample of 128 quasars found 6 sources scintillating with a characteristic time-scale of < 2 hours, suggesting that nearby scattering screens in the ISM may have a covering fraction of a few percent. That is an important consideration for proposed surveys of the transient and variable radio sky.",
keywords = "ISM: structure, quasars: individual, techniques: high angular resolution",
author = "Bignall, {Hayley E.} and Hodgson, {Jeffrey A.}",
year = "2011",
month = sep,
doi = "10.1017/S1743921312000439",
language = "English",
isbn = "9781107019850",
series = "Proceedings of the International Astronomical Union",
number = "S285",
pages = "129--132",
editor = "Elizabeth Griffin and Hanisch, {Robert J.} and Seaman, {Robert L.}",
booktitle = "New Horizons in Time-Domain Astronomy",
edition = "S285",
}
