Burst Transient Frequency
		Note:  The following response was published on the AAVSO GRB list server regarding the number of burst transients to be expected following the launch of HETE2 this summer.  The following was the response from Arne Hendon, a professional astronomer associated with the Naval Observatory, Flagstaff Station (nofs)
			Aaon Price of AAVSO submitted this estimate of GCN volume to the list server for comment. Localizations: Hete: 2 per week Other: .5 per week (current average since Compton fell) So, about 10 localizations per month. Half will be in your hemisphere, so about 5 per month? Half of that will be lost to the moon, so about 2.5 good GRBs per month will be the average. Gives us one week between GRBs to rest up! Alas, the satellite is going to hug the equator so it doesnt look like we will get to eaves drop on its transmissions. :) Aaron Price, Technical Assistant, UNIX, CGI. American Association of Variable Star Observers Arne Hendon responded as follows: Actually, it is a little worse than that since you haven't included the sun (it is up ~1/2 of the time, after all) and weather.  The moon is a little less of a problem, especially for amateurs, since you will be looking at the bright part of the burst.  On the other hand, us pros get to look on more than one night per burst, so we will be even busier than the amateurs!   What I would dearly love to see is some amateur in a good site who is willing to do the UBVRI photometric calibration of each field. That takes many hours of my time per burst currently, and I see it just getting worse after HETE. Arne Arne went on to write: Aaron asked off-line how many alert notices should be received from HETE2.  Now, I'm not associated with the spacecraft and am just repeating things I've gleaned from various contacts, so don't believe everything I say. The gamma-ray detectors cover a large fraction of the sky, so I'd expect about the same number of bursts as for BATSE (maybe one every day or so).  No directional information; you get that from either the Xray detectors or from time-of-delay triangularization ala IPN.   The Xray detectors cover ~1/4 of the sky at low resolution (say 10arcmin localizations), and ~1/8 of the sky at high resolution (say 30arcsec localizations). So the Xray localizations will occur once/week or so. The Xray localizations occur within seconds after a burst and are generated on-satellite.  The "alert" notice does not contain localization info, but occurs as soon as a burst is identified.  Then several "flight" notices occur as the spacecraft analyzes the burst and calculates increasingly more accurate positions.  The 15mins-2hr delay Aaron mentioned are more sophisticated localization analyses that are still automated, but groundbased.  Even more improved positions are possible with human intervention, but hours after a burst.  So Aaron, you will see a flood of GCN messages for every well-detected burst.   As for a photometry table:  sure, if you access the NOFS web site, you get a finding chart, jpeg images of the field, and astrometric/photometric data for all stars.  Why not include all of these on the AAVSO web site?  The chart and table will be a *very* small increment to the jpeg images. The more you can offload from the NOFS site, the better. Arne