H.E.S.S. discovery of a new blazar: RGB J0152+017 (fwd)

[Berrie Giebels <berrie@llr.in2p3.fr>]

Dear all, here is an interesting announcement.

---------- Forwarded message ----------
Date: Wed, 21 Nov 2007 15:16:13 +0100 (CET)
From: Michael Punch <punch@apc.univ-paris7.fr>
Subject: H.E.S.S. discovery of a new blazar: RGB J0152+017

Dear Colleagues,

  We are happy to inform you that the H.E.S.S. collaboration has just 
discovered VHE emission from a mid-distance range BL Lac, RGB J0152+017 
(z=0.08).  We are planning to send an Astronomer's Telegram on this (text 
below), but prefer to give you this information somewhat in advance and 
directly.  Please let us know if you have any questions, plans for observation 
which could be coordinated, etc., and don't hesitate to forward this to members 
of your collaboration concerned with AGNs,

  Best Regards,
    Michael Punch, for the AGN group of the H.E.S.S. collaboration.

-----------------------------------------------------------------
  Michael Punch,
  Astroparticule et Cosmologie (APC), CNRS,
  Universite Paris 7 Denis Diderot,
  10, rue Alice Domon et Leonie Duquet,
  F-75205 Paris Cedex 13, France,
  +33-1-57.27.60.81; fax +33-1-57.27.60.71 e-mail punch@in2p3.fr
-----------------------------------------------------------------

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H.E.S.S. discovers VHE gamma-rays from the BL Lac RGB J0152+017

Dalibor Nedbal (Prague University),
Wystan Benbow (Max-Planck-Institut fuer Kernphysik, now at Harvard-Smithsonian 
Center for Astrophysics),
Luigi Costamante (Max-Planck-Institut fuer Kernphysik, now at HEPL/KIPAC),
Berrie Giebels (Laboratoire Leprince Ringuet - IN2P3/CNRS),
Sarah Kaufmann (Landessternwarte Heidelberg),
Martin Raue (Max-Planck-Institut fuer Kernphysik),
Ladislav Rob (Prague University),
Stefan Wagner (Landessternwarte Heidelberg),
on behalf of the H.E.S.S. (High Energy Stereoscopic System) collaboration

We report on the H.E.S.S. discovery of VHE gamma-rays from the BL Lac object 
RGB J0152+017. H.E.S.S. observed the source from Oct 30 to Nov 14, 2007 for a 
total of ~14h live time. A preliminary on-site analysis resulted in a ~7 sigma 
detection of the source with an average flux level of ~2% Crab above 250 GeV. 
On the night Nov 12-13 the source showed indication for a higher flux state 
resulting in a ~5 sigma detection in less than 2h observation time. SWIFT and 
RXTE ToO observations yielded a detection with both instruments at the ~1 mCrab 
level (2-10 keV). Due to observing restrictions, the source could not be 
observed after Nov 13-14. We encourage other observatories to conduct follow up 
observations of the source to confirm a possible high VHE flux state and to 
collect a MWL data-sample of this newly detected VHE source.