- GCN/BACODINE POSITION NOTICE
- GCN NOTICE
TITLE: GCN/MAXI NOTICE
NOTICE_DATE: Mon 07 Sep 15 16:42:20 UT
NOTICE_TYPE: MAXI Unknown Source Position
EVENT_ID_NUM: 272520070
EVENT_RA: 223.90d {+14h 55m 35s} (J2000),
224.16d {+14h 56m 39s} (current),
223.05d {+14h 52m 13s} (1950)
EVENT_DEC: -46.94d {-46d 56' 08"} (J2000),
-47.00d {-46d 59' 54"} (current),
-46.73d {-46d 44' 01"} (1950)
EVENT_ERROR: 1.0 [deg radius, stat+sys, 90% containment]
EVENT_FLUX: 2741.0 +- 0.0 [mCrab]
EVENT_DATE: 17272 TJD; 250 DOY; 15/09/07
EVENT_TIME: 57653.00 SOD {16:00:53.00} UT
EVENT_TSCALE: 10s
EVENT_EBAND: Low, 2-4 keV
SUN_POSTN: 165.95d {+11h 03m 49s} +6.01d {+06d 00' 22"}
SUN_DIST: 73.69 [deg]
MOON_POSTN: 102.95d {+06h 51m 49s} +17.66d {+17d 39' 34"}
MOON_DIST: 123.96 [deg]
MOON_ILLUM: 27 [%]
GAL_COORDS: 323.94, 10.81 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS: 235.84,-28.81 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS: MAXI Unknown Source Position. GRB or unknown X-ray Transient.
- GCN NOTICE
TITLE: GCN/MAXI NOTICE
NOTICE_DATE: Mon 07 Sep 15 17:16:20 UT
NOTICE_TYPE: MAXI Unknown Source Position
EVENT_ID_NUM: 272520070
EVENT_RA: 224.84d {+14h 59m 23s} (J2000),
225.11d {+15h 00m 27s} (current),
223.99d {+14h 55m 58s} (1950)
EVENT_DEC: -47.59d {-47d 35' 30"} (J2000),
-47.65d {-47d 39' 12"} (current),
-47.39d {-47d 23' 34"} (1950)
EVENT_ERROR: 1.0 [deg radius, stat+sys, 90% containment]
EVENT_FLUX: 1464.0 +- 0.0 [mCrab]
EVENT_DATE: 17272 TJD; 250 DOY; 15/09/07
EVENT_TIME: 57653.00 SOD {16:00:53.00} UT
EVENT_TSCALE: 10s
EVENT_EBAND: Low, 2-4 keV
SUN_POSTN: 165.97d {+11h 03m 54s} +6.00d {+05d 59' 50"}
SUN_DIST: 74.55 [deg]
MOON_POSTN: 103.26d {+06h 53m 03s} +17.64d {+17d 38' 16"}
MOON_DIST: 124.24 [deg]
MOON_ILLUM: 27 [%]
GAL_COORDS: 324.20, 9.93 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS: 236.78,-29.23 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS: MAXI Unknown Source Position. GRB or unknown X-ray Transient.
- GCN Circular #18246
Y. E. Nakagawa (JAXA), H. Negoro, (Nihon U.), M. Serino (RIKEN),
M. Ishikawa, S. Nakahira, S. Ueno, H. Tomida, M. Kimura(JAXA),
T. Mihara, M. Sugizaki, M. Shidatsu, J. Sugimoto, T. Takagi, M. Matsuoka
(RIKEN),
N. Kawai, Y. Tachibana, T. Yoshii (Tokyo Tech),
A. Yoshida, T. Sakamoto, Y. Kawakubo, H. Ohtsuki (AGU),
H. Tsunemi, R. Imatani (Osaka U.), M. Nakajima, T. Masumitsu, K. Tanaka (Nihon
U.),
Y. Ueda, T. Kawamuro, T. Hori (Kyoto U.), Y. Tsuboi, S. Kanetou (Chuo U.),
M. Yamauchi, D. Itoh (Miyazaki U.), K. Yamaoka (Nagoya U.), M. Morii (ISM)
report on behalf of the MAXI team:
The MAXI/GSC nova alert system triggered a bright uncatalogued X-ray transient source at
16:00:50 UT on 7 September 2015. Assuming that the source flux was constant over the transit,
we obtain the source position at
(R.A., Dec) = (224.845 deg, -47.592 deg) = (14 59 22, -47 35 31) (J2000)
with a 90% C.L. statistical error of 0.06 deg.
There is an additional systematic uncertainty of 0.1 deg (90% containment radius).
The X-ray flux averaged over the scan was 1464 +- 75 mCrab (4-10keV, 1 sigma error).
There was no significant excess flux in the previous transit at 14:28 UT on 7 September 2015
with an upper limit of 20 mCrab.
- GCN Circular #18247
P. A. Evans (U. Leicester) reports on behalf of the Swift team:
Swift has initiated a series of observations, tiled on the sky, of the
MAXI GRB 150907A. Automated analysis of the XRT data will
be presented online at
http://www.swift.ac.uk/xrt_products/TILED_GRB00048
Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. The probability of
finding
serendipitous sources, unrelated to the MAXI event is high: any X-ray source
considered to be a probable afterglow candidate will be reported via a GCN
Circular
after manual consideration.
Details of the XRT automated analysis methods are detailed in Evans et
al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).
This circular is an official product of the Swift-XRT team.
- GCN Circular #18250
J.A. Kennea (PSU), B. Sbarufatti (INAF-OAB/PSU), T.G.R. Roegiers (PSU),
J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A. D'ai
(INAF-IASFPA), A. Maselli (INAF-IASFPA), A. Melandri (INAF-OAB), D.N.
Burrows (PSU) and P.A. Evans (U. Leicester) report on behalf of the
Swift-XRT team:
Swift-XRT has performed follow-up observations of the MAXI-detected
burst GRB 150907A (Nakagawa et al. GCN Circ. 18246) in a series of
observations tiled on the sky. The total exposure time is 1.7 ks,
distributed over 4 tiles; the maximum exposure at a single sky location
was 1.1 ks. The data were collected between T0+8.8 ks and T0+18.8 ks,
and are entirely in Photon Counting (PC) mode.
One uncatalogued X-ray source has been detected, it is below the RASS
limit and shows no definitive signs of fading. Therefore, at the
present time we cannot confirm this as the afterglow. Details of this
source are given below:
Source 1:
RA (J2000.0): 225.0526 = 15:00:12.62
Dec (J2000.0): -47.7084 = -47:42:30.3
Error: 6.0 arcsec (radius, 90% conf.)
Count-rate: 0.037 +/- 0.010 ct s^-1
Flux: (2.50 +/- 0.70)e-12 erg cm^-2 s^-1 (observed, 0.3-10 keV)
The results of the XRT-team automatic analysis of the tiled XRT
observations, including a position-specific upper limit calculator, are
available at http://www.swift.ac.uk/xrt_products/TILED_GRB00048.
This circular is an official product of the Swift-XRT team.
- GCN Circular #18255
M. De Pasquale (UCL-MSSL) and D. Malesani (DARK/NBI) report on behalf of
the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 150907A
8821 s after the MAXI trigger (Suzuki et al., GCN Circ. 18246).
No optical source consistent with the XRT Source 1 position given in
Kennea et al. (GCN Circ. 18250) is detected in the summed u band exposures.
We note however, that there is source in the DSS catalogue consistent
with the XRT Source 1 position.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the exposure
for source 1 is:
Filter T_start(s) T_stop(s) Exp(s) Mag
u 8821 18835 336 >19.5
The magnitudes in the table are not corrected for the Galactic
extinction due
to the reddening of E(B-V) = 0.08 in the direction of the burst
(Schlegel et al. 1998).
- GCN Circular #18311
J.A. Kennea (PSU), B. Sbarufatti (INAF-OAB/PSU), J.P. Osborne (U.
Leicester), K.L. Page (U. Leicester), A. D'ai (INAF-IASFPA), A. Maselli
(INAF-IASFPA), A. Melandri (INAF-OAB), D.N. Burrows (PSU) and P.A.
Evans (U. Leicester) report on behalf of the Swift-XRT team:
Swift-XRT has conducted further observations of the field of the
MAXI-detected burst GRB 150907A (Nakagawa et al. GCN Circ. 18246). The
observations now extend from T0+8.8 ks to T0+489.4 ks. The source
previously reported by Kennea et al. (GCN Circ. 18250), "Source 1", is
fading with 3-sigma significance, and is therefore likely the GRB
afterglow. The position of this source is RA, Dec=225.0528, -47.7080
which is equivalent to:
RA (J2000): 15:00:12.68
Dec(J2000): -47:42:28.8
with an uncertainty of 6.8 arcsec (radius, 90% confidence). This
position is 10.9 arcmin from the MAXI position. The source is fading
with alpha >0.5.
The results of the XRT-team automatic analysis of the likely afterglow
are at http://www.swift.ac.uk/xrt_products/TILED_GRB00048/index_1.php.
The results of the full analysis of the tiled XRT observations are
available at http://www.swift.ac.uk/xrt_products/TILED_GRB00048.
This circular is an official product of the Swift-XRT team.
Previous IAU Circulars 