[vsnet-alert 12389] FWD ATEL 3021 and 3025 - GT Mus

[F L]

Japanes MAXI/GSC team outburst notification :-

http://www.astronomerstelegram.org/?read=3021

SWIFT confirmation and follow up :-

http://www.astronomerstelegram.org/?read=3025

This object is too bright for meaningful data from ASAS3 survey, and the data too noisy for subtle variation to be noted.

Experienced smateur photometrists may be able to follow such a star down to the 0.02 magnitude level, however.

Without an equivalent baseline lightcurve extra variation may not be readily discernible, however any flickering detected now during outburst event could be compared to a quiet time lightcurve taken at a later time.

The future of space missions, and to some extent variability surveys, in a pro-am context lies in the future of satellite and ground survey missions of this sort, and those are going to be high energy, mostly xrays, or NIR to MIR to even FIR.

Such a star as this is of an apparent magnitude that amateur exoplanet searchers and transit measurers feel confident of monitoring whilst looking for lowest amplitude changes, so following such an object during an xray outburst alert will reveal anything of interest there is to reveal, whilst adding to the sum of knowledge in these objects.  Solar xray flares, for instance, can be accompanied by white light flares, although not necessarily so.  The most energetic usually are.  Strong stellar xray flares detected by MAXI/GSC or SWIFT or whichever satellite could therefore have white light signals attendant to them, and if nothing else the Lx to Lopt ratio measured and compared to Solar equivalents or just studied within their own context.

It's not as easy and/or gimmicky as doing a quick run on some outbursting object and getting a guaranteed cycle or two of readily parameterised superhump or orbital signature (just stick the lightcurve data into a periodogram analysis package, et voila), and really would need to be undertaken to a proper recognised photometric standard filter system, say Johnson V at least.

But it has the potential to advance knowledge and do new and real science.

Even a nondetection of a whitelight signal would say something if this nondetection was at a threshold such that the equivalent white light to xray flux ratio on the Sun would've meant an optical detection.  That is, it'd tell us that the xray flaring there is subtley different to any equivalent Solar analogue.

Whether it's too late to bother with this object now or not I do not know, flares are very transient and I'm not overly sure of the timescale, but as these are major flares and likely have a decay time, an immediate optical response may have been of interest.

Something new to try for, instead of the same old dull stuff that's more than catalogued and measured and categorised as optically possible already.

The SWIFT data lives here

http://swift.gsfc.nasa.gov/cgi-bin/sdc/list?seq=sw00031864001.002

If you select sw00031864001u.cat under UVOT Products in that list (and select download as tar file) then download it you will get a fits table data file.  You can load that into TopCat or wherever and find a list of source objects' magnitudes, however it's for the UVM2 UV filter.  Sometimes later SWIFT images will include such tables for U, B and V, depending on the followup, but usually it's only the UVOT "filter of the day", and often that filter is the UV UW2 one.

But for some stellar objects you get one for several UVOT filters, and they could be used to generate sequences when they include V, for people who like that sort of thing.

Cheers

John