Astrophysics Group

Variability studies

Radio Source Variability

151 MHz

The variability of radio sources at 151 MHz has been studied in detail using the CLFST, as part of the 7C survey. See:

• “The 7C survey of radio sources at 151 MHz – a search for low-frequency variability”
  McGilchrist & Riley 1990 MNRAS, 246, 123;
• “High-resolution observations of a complete sample of radio sources variable at 151 MHz”
  Riley & Warner 1994, MNRAS, 269, 166;
• “Radio variability in a complete sample of extragalactic sources at 151 MHz”
  Riley, 1993, MNRAS, 260, 893;
• “The Nature of a Homogeneous Sample of Compact Radio Sources Variable at 151 MHz”
  Minns, Riley, Warner, Rioja & RУЖttgering, 1998, IAU Colloquium 164, p.281;
• “Compact radio sources variable at 151MHz – I. Catalogue of sources”
  Minns & Riley, 2000, MNRAS, 315, 839;
• “Compact radio sources variable at 151MHz – II. High-resolution observations of an unbiased sample”
  Minns & Riley, 2000, MNRAS, 318, 827.

408 MHz and 1420 MHz

In addition, some of the 151-MHz variability study fields have been observed at 408 MHz and 1.4 GHz with the DRAO synthesis telescope. See:

• “408-MHz observations of two fields in the region 10^h30^m, +46ТА – I. The surveys”
  Green & Riley 1995, MNRAS, 274, 324;
• “408-MHz observations of two fields in the region 10^h30^m, +46ТА – II. A variability study”
  Riley & Green 1995, MNRAS, 275, 527;
• “A 408-MHz variability study of two fields in the region 6^h30^m, +45ТА
  Riley & Green 1998, MNRAS, 301, 203.

“P”enticton source lists

The source lists from these DRAO surveys are available here. These are “nnP” source lists, where “nn” is the number of the “P” (for Penticton, the site of DRAO) survey.

1. From Green & Riley (1995), the 51P and 52P source lists at 408 MHz, plus the 53P and 54P source lists at 1420 MHz.
2. From Riley & Green (1998), the 67P and 68P source lists at 408 MHz, plus the 69P and 70P source lists at 1420 MHz.

These source lists each contain (see Green & Riley 1995 for details): 1) the source name; 2) the source right ascension and declination (B1950.0); 3) the peak flux density (/mJy); 4) the integrated flux density (/mJy); 5) the primary beam correction, and 6) the signal/noise ratio of the source. Notes: a) an “*” after the integrated flux density indicates that two or more peaks have been integrated together; b) in the 67P to 70P lists, a few sources do not have integrated flux densities, as they are near bright sources, or on grating rings.

Julia Riley/MRAO, Cambridge, UK/julia@mrao.cam.ac.uk
Dave Green/MRAO, Cambridge, UK/dag@mrao.cam.ac.uk