Re: Discovery of another optically violently variable quasar 4C 09.57

[Tass Mailing List <tass@mail.alembic.net>]

Date: Mon, 24 Mar 2008 22:16:50 +0900 (JST)
From: Seiichi Yoshida <comet@aerith.net>
To: tass@mail.alembic.net
Subject: Re: Discovery of another optically violently variable quasar 4C 09.57

Dear colleagues,

Stefan Karge and Taichi Kato pointed me that this is a well-known
blazar, and the outburst in 2007 we reported has been already
discovered and reported at that time by Stefan Karge.

So, this it "not" our discovery. Very sorry for our false alarm.

Here is the Stefan Karge's mail:

> Dear Seiichi Yoshida,
>
> the 2007 outburst of OVV Quasar OT081 = PKS 1749+096 = 4C 09.57
> was already published by me, S. Karge, via vsnet-alert 9356
> in 2007, titled <Blazar PKS 1749+096 in outburst>,
> posted on Wed May 16 22:03:33 JST 2007.
>
> I independently discovered the outburst on the 25th of April,
> 2007 at Taunus Observatory:
> 25-Apr-2007, 23h55 UT:  14.12 CV (0.02), 24" (2x20sec)
> 08-May-2007, 04h56 UT:  14.11 CV (0.03), 14" (1x100sec)
> 16-May-2007, 00h13 UT:  14.52 CV (0.02), 24" (2x20sec)
>
> A lightcurve throughout the observing season 2007, together with
> data on the history of the discovery, were also published at:
> Karge, S., 2007, The Astronomer, Vol. 44, No 520, 100.
>
> My last observation of OT 081 dates back to 09-Feb-2008 and
> showed the QSO near minimum brightness of 18.36C
> (see vsnet-campaign-blazar 363).

Best regards,

--
Seiichi Yoshida
comet@aerith.net
http://www.aerith.net/