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GCN Circular 17988

Fermi GBM Observations is no longer triggerin on V404 Cyg
2015-07-02T20:35:38Z (8 years ago)
Peter Jenke at MSFC <>
P. Jenke (UAH) and E. Burns (UAH) report on behalf of Fermi GBM team:

On June 15, 18:59:01.20 UTC, Fermi/GBM triggered (G. Younes et al., GCN 17932)
on a hard X-ray flare from V404 Cyg.  For the next 12 days, GBM triggered
169 times on flares from this source.  Many of the triggers arose, not
from individual events but from Earth occultation edges of longer events.
The last GBM trigger for V404 Cyg occurred on June 27, 23:27:50.54 UTC and
we assume that the source has fallen below GBM�s threshold on its return
to quiescence.  

Quarter day integrated Earth occultation (PI C. A. Wilson-Hodge) results
show that V404 Cyg reached a maximum flux in the 25-50 keV band of 7.2 crab
on June 26 while the source reached a maximum flux in the 100-300 keV band
of 5.2 crab on June 19.

A list of V404 Cyg triggers can be found in the trigger catalog by searching
for the 'TRANSNT' trigger type and confirming the location.
The catalog can be browsed at:
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