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GCN Circular 35666

GRB 240204A: Swift detection of a burst
2024-02-04T15:33:54Z (4 months ago)
K.L. Page at U Leicester <>

S. B. Cenko (GSFC), C. Gronwall (PSU), J.D. Gropp (PSU),
J. A. Kennea (PSU) and K. L. Page (U Leicester) report on behalf of
the Neil Gehrels Swift Observatory Team:

Swift/BAT triggered on the Fermi/GBM reported long GRB 240204A (GCN #35664). 
Due to a telemetry outage, no realtime BAT data are available. 

The XRT began observing the field at 15:10:12.2 UT, 154 seconds
after the Fermi/GBM trigger. Using promptly downlinked data we find an
uncatalogued X-ray source located at RA, Dec 104.18190, 1.02767 which
is equivalent to:
   RA(J2000)  = 06h 56m 43.66s
   Dec(J2000) = +01d 01' 39.6"
with an uncertainty of 4.0 arcseconds (radius, 90% containment). This
position may be improved as more data are received; the latest position
is available at 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 6.45
x 10^21 cm^-2 (Willingale et al. 2013). 

Due to a telemetry outage, there are no UVOT data available at this time. 

Burst Advocate for this burst is S. B. Cenko (brad.cenko AT 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information:

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