Journal of The Korean Astronomical Society (천문학회지)

The Korean Astronomical Society (한국천문학회)
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HOW TO MONITOR AGN INTRA-DAY VARIABILITY AT 230GHZ

  • Kim, Jae-Young (Department of Physics and Astronomy, Seoul National University) ;
  • Trippe, Sascha (Department of Physics and Astronomy, Seoul National University)
  • Received : 2012.12.21
  • Accepted : 2013.02.05
  • Published : 2013.04.30
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Abstract

We probe the feasibility of high-frequency radio observations of very rapid flux variations in compact active galactic nuclei (AGN). Our study assumes observations at 230GHz with a small 6-meter class observatory, using the SNU Radio Astronomical Observatory (SRAO) as an example. We find that 33 radio-bright sources are observable with signal-to-noise ratios larger than ten. We derive statistical detection limits via exhaustive Monte Carlo simulations assuming (a) periodic, and (b) episodic flaring flux variations on time-scales as small as tens of minutes. We conclude that a wide range of flux variations is observable. This makes high-frequency radio observations-even with small observatories-a powerful probe of AGN intra-day variability; especially, those which complement observations at lower radio frequencies with larger observatories like the Korean VLBI Network (KVN).

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