TITLE:   GCN CIRCULAR
NUMBER:  22740
SUBJECT: IPN Triangulation of GRB 180523A
DATE:    18/05/28 05:37:28 GMT
FROM:    Anna Kozlova at Ioffe Institute  <ann_kozlova@mail.ioffe.ru>

K. Hurley, on behalf of the IPN,

I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin,
on behalf of the HEND-Odyssey GRB team,

A. Kozlova, S. Golenetskii, R. Aptekar, D. Frederiks, D.Svinkin,
and T. Cline on behalf of the Konus-Wind team,

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,

S. Barthelmy, J. Cummings, H. Krimm, and D. Palmer,
on behalf of the Swift-BAT team, and

W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr,
on behalf of the GRS-Odyssey GRB team, report:

The long-duration GRB 180523A (CGBM detection: Tezuka et al., GCN Circ. 
22738)
was detected by Konus-Wind, INTEGRAL (SPI-ACS), Mars-Odyssey (HEND), 
CALET (CGBM),
and Swift(BAT) at about 66029 s UT (18:20:29).
The burst was outside the coded field of view of the BAT.

We have triangulated it to a preliminary, 3 sigma error box whose 
coordinates are:
---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
    96.875 (06h 27m 30s) +45.896 (+45d 53' 45")
  Corners:
    94.906 (06h 19m 37s) +45.533 (+45d 31' 58")
    97.577 (06h 30m 18s) +47.934 (+47d 56' 02")
    98.890 (06h 35m 34s) +46.191 (+46d 11' 26")
    96.260 (06h 25m 02s) +43.715 (+43d 42' 53")
  ---------------------------------------------
The error box area is 5.54 sq. deg, and its maximum
dimension is 4.3 deg (the minimum one is 1.8 deg).
The Sun distance was 37 deg.

This box may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB180523_T66028/IPN/

The Konus-Wind time history and spectrum will be given in a forthcoming
GCN Circular.