Rapid variability of extragalactic radio sources

Abstract

view Abstract Citations (180) References (23) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Rapid Variability of Extragalactic Radio Sources Heeschen, D. S. ; Krichbaum, Th. ; Schalinski, C. J. ; Witzel, A. Abstract Thirty-one extragalactic radio sources have been observed at 2-4 hr intervals for 3-4 days at each of three epochs. The 15 compact sources in the sample appear to display two types of variability. One is probably weak flickering caused by refractive interstellar scintillation. The other is a larger amplitude variability, which is characterized by a narrow range of timescales of about 1-2 days. Three possible causes of the second type are discussed: (1) intrinsic variability; (2) scintillation from a very narrow disk component of the ISM; and (3) scintillation from clouds associated with a particular region of the ISM. It is suggested that the latter is the more likely explanation. Publication: The Astronomical Journal Pub Date: December 1987 DOI: 10.1086/114583 Bibcode: 1987AJ.....94.1493H Keywords: Astronomical Spectroscopy; Extragalactic Radio Sources; Periodic Variations; Radiant Flux Density; Scintillation; Centimeter Waves; Temporal Distribution; Astrophysics; RADIO SOURCES: GENERAL; RADIO SOURCES: GALAXIES full text sources ADS | data products NED (33) SIMBAD (32)