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).

ABSTRACT
1. INTRODUCTION
2. ANALYSIS
    2.1 Noise Limits
    2.2 Source Selection
    2.3 Detection Limits of Variability
3. DISCUSSION
4. CONCLUSIONS
REFERENCES

• JAE-YOUNG KIM(Department of Physics and Astronomy, Seoul National University)
• SASCHA TRIPPE(Department of Physics and Astronomy, Seoul National University) Corresponding Author