[vsnet-alert 10884] FWD ATEL 1888 (a QSO OVV outburst)

[qso at Safe-mail.net]

http://www.astronomerstelegram.org/?read=1888

This is something of a large amplitude outburst for an OVV, five mags in an 'optical' passband.

If the outburst is fairly colourless it should be no less than V 16 ish.

It'll give some folk chance to eyeball something at z ~ 1.8, which is pretty distant (dependent on Hubble constant, terms and conditions apply, though likely available in all areas).  [Don't get z' and z confused, one's an SDSS photometric passband, t'other's the cosmological red shift... ...it's a spectroscopically confirmed, via SDSS spectra, QSO].

The radio source is polarised, so likely something akin to Seiichi's MisV QSO, an OVV where we're nearly staring staring straight down some relativistic jet sort of thing.  Whether study of these repeatable outbursts in order to elucidate outbursting - relativistic jet combo phyisics in the photometric optical has potential utility for elucidating the unrepeatable GRB outbursting - relativistic jet combo physics in the photometric optical, I dunno, maybe time series might say something interesting, using same sort of sampling regimes as for GRB stuff.  However, obviously the event is now already past the initial outburst stage.  Maybe monitoring these sorts of OVVs in general for outbursts might be useful in this relativistic jet context, and make a change from sixteenth mag CVs?

One paper seems to call it a 'binary quasar', but it doesn't really read as if they are in any way connected (the B quasar is z ~ 0.5 nearer than A!), the paper seems to be more interested in statistical clumping of QSOs, overdensities, than physical association.  [I've seen half baked "amateurs" call line of sight stars "binaries", weird to see pros doing it for QSOs.  I mean, line of sight QSOs towards the Virgo Supercluster direction, helluva shock.]

The "B" quasar's SDSS J123936.52+044249.3 if anyone really wants to check if its jumped to mag 14 or so from base 18 to 19, but it doesn't seem to be either a radio or xray source, unlike its "A" pal, it's just in the same direction and quasar coloured as far as I can see (it is spectroscopically confirmed a QSO mind).

A null result is also information.

John Greaves