- GCN/BACODINE POSITION NOTICE
TITLE: GCN/SuperAGILE NOTICE
NOTICE_DATE: Mon 26 Jan 09 08:36:11 UT
NOTICE_TYPE: SuperAGILE GRB Ground Position
TRIGGER_NUM: 1017
GRB_RA: 3.848d {+00h 15m 23s} (J2000),
3.987d {+00h 15m 57s} (current),
3.098d {+00h 12m 24s} (1950)
GRB_DEC: +81.365d {+81d 21' 54"} (J2000),
+81.415d {+81d 24' 55"} (current),
+81.087d {+81d 05' 13"} (1950)
GRB_ERROR: 3.00 [arcmin radius, statistical plus systematic]
GRB_INTEN: 298.177 203.246 [X & Y cnts]
GRB_SIGNIF: 8.91 8.43 [sigma]
GRB_DATE: 14857 TJD; 26 DOY; 09/01/26
GRB_TIME: 7275.00 SOD {02:01:15.00} UT
SUN_POSTN: 308.91d {+20h 35m 39s} -18.64d {-18d 38' 27"}
SUN_DIST: 103.60 [deg] Sun_angle= -3.7 [hr] (East of Sun)
MOON_POSTN: 309.35d {+20h 37m 25s} -18.84d {-18d 50' 14"}
MOON_DIST: 103.74 [deg]
MOON_ILLUM: 0 [%]
GAL_COORDS: 121.51, 18.59 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS: 69.59, 64.57 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS: SuperAGILE GRB Coordinates.
COMMENTS: This is a GRB.
COMMENTS: SuperAGILE ground GRB coordinates
- red DSS finding chart
ps-file
- GCN Circular #8852
Y. Evangelista, E. Del Monte, I. Donnarumma, M. Feroci, F. Lazzarotto, L.
Pacciani, P. Soffitta, E. Costa, I. Lapshov, M. Rapisarda (INAF/IASF
Rome), A. Giuliani, S. Vercellone, A. Chen, S. Mereghetti, A. Pellizzoni,
F. Perotti, P. Caraveo (INAF/IASF Milan), A. Bulgarelli, F. Gianotti, M.
Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, M. Galli,
(INAF/IASF Bologna), M. Tavani, G. Pucella, F. D'Ammando, V. Vittorini, A.
Argan, A. Trois, G. Piano, S. Sabatini (INAF/IASF Rome), G. Barbiellini,
F. Longo E. Moretti (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2),
M. Prest, E. Vallazza (Universita` dell'Insubria), P. Lipari, D. Zanello
(INFN Roma-1), and P. Giommi, C. Pittori, B. Preger, P. Santolamazza, F.
Verrecchia (ASDC) and L. Salotti (ASI), on behalf of the AGILE Team,
report:
"SuperAGILE detected a gamma ray burst on 26 January 2009, at 02:01:15 UT.
The event had a duration of about 60 s in the 20-60 keV energy range,
with a structure composed of two separated main peaks. Assuming a
Crab-like energy spectrum, the peak flux on 1-s timescale was 1.5E-07
erg/cm2/s.
The burst position was reconstructed as (RA, Dec)
(3.848 deg, 81.365 deg), which is:
RA(J2000) = 00h 15m 23.50s
Dec(J2000) = 81d 21' 53.78"
with an uncertainty of 3' radius. The given uncertainty accounts
for both the statistical and systematic errors.
An analysis of the AGILE Gamma Ray Imager (GRID) data is in progress."
This message may be cited.
- GCN Circular #8854
M. C. Stroh (PSU) reports on behalf of the Swift-XRT team:
We have analyzed the first 3.1 ks of XRT data for GRB 090126A
(Evangelista et al., GCN Circ. 8852), from T+48 ks to T+60 ks after
the trigger. The data is all taken in Photon Counting (PC) mode.
Using 1435 s of XRT Photon Counting mode data and 2 UVOT images, we
find an astrometrically corrected X-ray position (using the XRT-UVOT
alignment and matching to the USNO-B1 catalogue): RA, Dec = 3.6577,
81.3733 which is equivalent to:
RA (J2000): 00 14 37.85
Dec (J2000): +81 22 24.0
with an uncertainty of 2.2 arcsec (90% confidence).
This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions.
Position enhancement is described by Goad et al. (2007, A&A, 476, 1401 http://www.swift.ac.uk/xrt_positions/Goad.pdf)
, the current algorithm is an extension of this method.
A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.8 (+0.6, -0.4). The best-
fitting absorption column is 1.8 (+/- 1.8) x 10^21 cm^-2, which is
consistent with the Galactic value of 1.4 x 10^21 cm^-2 (Kalberla et
al. 2005). The observed (unabsorbed) flux in the 0.3-10.0 keV band is
1.49 (1.9) x 10^-12 erg cm^-2 s^-1.
The light curve shows a potentially decaying source which can be fit
using a single power-law decay with a slope, alpha = 1.2 (+/- 1.1).
Assuming the light curve decays at the current rate, we predict count
rates at T+24 and T+48 hours to be 1.6 x 10^-2 and 7.0 x 10^-3
respectively.
This is an official product of the Swift-XRT team.
- GCN Circular #8864
S. T. Holland (CRESST/GSFC/USRA), F. E. Marshall (NASA/GSFC), and
M. C. Stroh (PSU) report, on the behalf of the Swift/UVOT team:
The Swift/UVOT observed the field of GRB 090126A (Evangelista
et al. 2009, GCN Circ. 8852) starting approximately 48 ks after the
SuperAGILE detection. We find no new source, relative to the DSS or
USNO-B1.0 catalogue, or a variable source, inside the UVOT-enhanced
XRT error circle (Stroh et al. 2009, GCN Circ. 8854). Preliminary
3-sigma upper limits for detecting a source in the co-added images,
using an aperture-corrected 2.5 arcsecond radius circular aperture,
are
Filter T_start T_stop Exp(s) Mag
------------------------------------------
v 49,398 55,302 208 >20.1
b 48,033 71,752 3256 >22.7
u 47,960 71,155 333 >21.0
white 48,713 66,162 2022 >23.1
------------------------------------------
The quoted upper limits have not been corrected for the expected
Galactic extinction along the line of sight corresponding to a
reddening of E_{B-V} = 0.20 mag (Schlegel et al., 1998, ApJS, 500,
525). All photometry is on the UVOT photometry system described in
Poole et al. (2008, MNRAS, 383, 627).
- GCN Circular #8880
M. C. Stroh (PSU) reports on behalf of the Swift-XRT team:
Swift took an additional 7.6ks observation of GRB 090126A centered at T
+29ks after the trigger. The single uncatalogued X-ray source
previously reported by Stroh et al. (GCN Circ. 8854) shows fading
flux, confirming its afterglow nature.
The 0.3-10 keV light curve can be fit using a simple power law model
with decay index alpha = 1.42 +/- 0.13.
This is an official product of the Swift-XRT team.
Previous IAU Circulars 