eCite Digital Repository

Milliarcsecond Structure of Microarcsecond Sources: Comparison of Scintillating and Nonscintillating Extragalactic Radio Sources

Citation

Ojha, R and Fey, AL and Jauncey, DL and Lovell, JEJ and Johnston, KJ, Milliarcsecond Structure of Microarcsecond Sources: Comparison of Scintillating and Nonscintillating Extragalactic Radio Sources, The Astrophysical Journal, 614, (2 I) pp. 607-614. ISSN 0004-637X (2004) [Refereed Article]

DOI: doi:10.1086/423797

Abstract

We compare the milliarcsecond-scale morphology of scintillating and nonscintillating sources. The scintillating sources are drawn from those flat-spectrum extragalactic radio sources discovered, by the Micro-Arcsecond Scintillation-Induced Variability Survey, to have flux density variability at 5 GHz on timescales from hours to days. Intrinsic source structure information is obtained from previously published and/or publicly available 8.4 GHz Very Long Baseline Array images. A sample of low flux density (Sv=5 GHz. < 0.3 Jy) scintillating sources was compared with a sample of high flux density (Sv=5GHz ∼ 1 Jy) scintillators, as well as a sample of high flux density nonscintillators. All source samples meet the selection criteria of the Micro-Arcsecond Scintillation-Induced Variability Survey, thus ensuring that all three source samples are suitable for comparative study. We find that all scintillating sources (both low and high flux density samples) are significantly more core dominated than nonscintillating sources. Further, the overall source size of the scintillating sources is significantly smaller than that of nonscintillators. There does not appear to be any significant difference between the milliarcsecond-scale morphologies of low and high flux density scintillators. These results demonstrate that it is the core of the radio source that is scintillating.

Item Details

Item Type:Refereed Article
Research Division:Physical Sciences
Research Group:Astronomical and Space Sciences
Research Field:Galactic Astronomy
Objective Division:Expanding Knowledge
Objective Group:Expanding Knowledge
Objective Field:Expanding Knowledge in the Physical Sciences
Author:Lovell, JEJ (Dr Jim Lovell)
ID Code:45342
Year Published:2004
Web of Science® Times Cited:14
Deposited By:Physics
Deposited On:2007-07-11
Last Modified:2007-07-11
Downloads:0

Repository Staff Only: item control page