TITLE:   GCN CIRCULAR
NUMBER:  24372
SUBJECT: IPN Triangulation of GRB 190501A (long/bright)
DATE:    19/05/03 00:02:49 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@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. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,

A. Ursi, N. Parmiggiani, F. Verrecchia, A. Bulgarelli,
A. Trois, M. Marisaldi, C. Pittori, M. Tavani, Y. Evangelista,
I. Donnarumma, M. Cardillo, G. Piano, G. Minervini, A. Argan,
F. Lucarelli, A. Zoli, V. Fioretti, F. Fuschino, M. Pilia,
F. Longo, A. Giuliani on behalf of the AGILE 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, very bright GRB 190501A
(AGILE-MCAL detection: Ursi et al., GCN Circ. 24360;
AGILE-GRID detection: Lucarelli et al., GCN Circ. 24361;
AGILE-GRID refined position: Verrecchia et al., GCN Circ. 24363)
was detected by AGILE (MCAL, GRID), INTEGRAL (SPI-ACS), Konus-Wind,
Mars-Odyssey (HEND), and CALET (GBM), at about 19395 s UT (05:23:15).

We have triangulated it to a preliminary, 3 sigma error box
whose coordinates are:
  ---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
   173.591 (11h 34m 22s) +62.105 (+62d 06' 18")
  Corners:
   173.345 (11h 33m 23s) +61.440 (+61d 26' 24")
   174.192 (11h 36m 46s) +62.859 (+62d 51' 32")
   173.840 (11h 35m 22s) +62.766 (+62d 45' 57")
   173.007 (11h 32m 02s) +61.342 (+61d 20' 32")
  ---------------------------------------------
The error box area is about 691 sq. arcmin, and its maximum
dimension is 1.615 deg (the minimum one is 7.8 arcmin).
The Sun distance was about 95 deg.

This box may be improved.

The AGILE (GRID) refined position (RA, Dec, Rerr = 172.8, 64.1, 0.8 deg)
reported in Verrecchia et al. is inconsistent with the box, the
minimum distance between the box and the center of the AGILE (GRID) 
location is ~1.39 deg.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB190501_T19401/IPN

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