[vsnet-chat 2472] Re: [AAVSO-DIS] GRB notification process

[Taichi Kato <tkato>]

Re: [AAVSO-DIS] GRB notification process

>   Kato-san mentioned visual observing of an OT.  I think
> it will be possible with HETE since you will have arcmin
> to arcsec localizations within a few seconds after the
> burst.

   HETE II is expected to require significantly longer than a few seconds
to accurately (10') localize the burst (according to the HETE II team, this
is partly limited by the sampling bins and the ability of the on-board
computer).  So alerts can to be slower than BATSE triggers.  Those who wish
to see the earliest few seconds of the burst must still use the BATSE
triggers.  However, the delay of the optical emission in GRB 990123 to the
gamma-ray peak (though no one knows the t=0 optical brighteness) will make
HETE II-based OT search promising even if alerts are slower by ten seconds.
Furthermore, the chance can be larger when taking into account the
possibilities of gamma-ray precursors, and/or multiple peaks caused by
gravitational lensing.

   It may be interesting to note that no one replied when I brought GRB
OTs into the issue of VSNET before the discovery of the OT in 1997.
(And I must comment what was a pity HETE I failed to be entered in orbit
years ago!).

   Some further concern: how GRBs will be called in the year 2000
(GRB 000101 or GRB 20000101?)

Regards,
Taichi Kato

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