TITLE:   GCN CIRCULAR
NUMBER:  16238
SUBJECT: VHE gamma-ray observations by MAGIC of SWIFT Trigger 596958
DATE:    14/05/09 16:22:01 GMT
FROM:    Razmik Mirzoyan at MPI/MAGIC  <Razmik.Mirzoyan@mpp.mpg.de>

   On 23th April 2014 at 21:08:26 UT, the MAGIC telescopes received a
   GRB-like event alert from Swift (D'Elia et al., GCN16158). It was
   later pointed out that this event was probably not due to a GRB but
   to a flaring star (Xu et al., GCN16159; Drake et al., ATel 6121).
   The MAGIC telescopes started observations of the transient event at
   21:08:54 UT, about 30s after the alert was received, and
   kept collecting data for the next 3.3h.
   Data were taken in dark-night and under excellent weather conditions,
   at medium-low zenith angles (below 45deg).
   A preliminary analysis gave an integral flux upper limit of 1.2e-11 cm-2 s-1
   above E>200 GeV at 95% c.l., corresponding to 5.3% of the Crab Nebula flux
   above 200 GeV, assuming a Crab-like spectral index. The intra-minute light-curve
   above 200 GeV did not show any hint of transient signal.
   The MAGIC collaboration is open to collaborate with other teams on this
   observation.

   MAGIC is a system of two 17m-diameter Imaging Atmospheric Cherenkov
   Telescopes located at the Canary island of La Palma, Spain, and
   designed to perform gamma-ray astronomy in the energy range  from 50
   GeV to more than 50 TeV. Questions regarding the MAGIC observations
   should be directed to Razmik Mirzoyan ([1]Razmik.Mirzoyan@mpp.mpg.de)
   or Alessandro Carosi ([2]alessandro.carosi@oa-roma.inaf.it) and
   Saverio Lombardi ([3]saverio.lombardi@pd.infn.it).

   This message is quotable in publications

   -Razmik Mirzoyan, on behalf of the MAGIC Collaboration