[vsnet-grb-info 21478] IPN Triangulation of GRB 181227A (long)

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  23577
SUBJECT: IPN Triangulation of GRB 181227A (long)
DATE:    18/12/28 10:27:23 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin at 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,

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

A. Goldstein, M. S. Briggs, and C. Wilson-Hodge
on behalf of the Fermi GBM 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 181227A
(Fermi-GBM detection: Bissaldi & Veres, GCN Circ. 23569)
was detected by Fermi (GBM trigger 567584225), Konus-Wind,
INTEGRAL (SPI-ACS), Mars-Odyssey (HEND), and Swift (BAT)
at about 22620 s UT (06:17:00).
The burst was detected by Swift (BAT) during the slew and
no event data were captured (Sakamoto, Lien, and Pal'shin, priv. comm.).

We have triangulated it to a preliminary, 3 sigma error box
whose coordinates are:
---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
    29.889 (01h 59m 33s) -53.321 (-53d 19' 14")
  Corners:
    30.664 (02h 02m 39s) -52.621 (-52d 37' 16")
    30.861 (02h 03m 27s) -53.105 (-53d 06' 19")
    27.501 (01h 50m 00s) -54.693 (-54d 41' 35")
    27.344 (01h 49m 22s) -54.208 (-54d 12' 30")
  ---------------------------------------------
The error box area is about 1.13 sq. deg, and its maximum
dimension is 2.79 deg (the minimum one is 27.84 arcmin).
The Sun distance was about 84 deg.

This box may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB181227_T22619/IPN/

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