GCN Circular 2724
Subject
XRF 040912, identification of CXO sources
Date
2004-09-17T21:55:13Z (21 years ago)
Edited On
2024-11-18T10:07:10Z (7 months ago)
From
Alberto Castro-Tirado at Inst.de Astro. de Andalucia <ajct@iaa.es>
Edited By
Judith Racusin at NASA/GSFC <judith.racusin@nasa.gov> on behalf of Leo P. Singer at NASA/GSFC <leo.p.singer@nasa.gov>
J. Gorosabel (IAC-CSIC Granada), J. Cepa (IAC
Tenerife), A. de Ugarte Postigo (IAA-CSIC),
D. Martínez-Delgado (MPIfA Heidelberg), V. Casanova,
S. Guziy, M. Jelínek (IAA-CSIC, Granada), J. M.
Castro Cerón (San Fernando), H. Castaneda (IAC
Tenerife), D. Zucker, E. F. Bell (AIP Potsdam)
and A. J. Castro-Tirado (IAA-CSIC)
report:
"We have acquired optical images covering the
entire error box of the XRF 040912 detected by
HETE-2 (Ricker et al. GCN Circ. 2701) starting
on 12 Sep 21:27 UT (i.e. 7.25 hr after the event).
The observations were performed with the 4.2m
WHT (+PFC) at La Palma (16'x 16' FOV).
The observing log follows:
-----------------------------------
Date 2004 UT Exp.Time (s) Filter
-----------------------------------
12 Sep 21:27:56 1455 B
12 Sep 21:53:45 900 V
13 Sep 04:26:41 900 V
13 Sep 21:07:58 1200 V
16 Sep 01:49:11 300 I
16 Sep 01:58:17 300 I
16 Sep 02:05:06 300 I
16 Sep 02:11:17 300 I
16 Sep 02:18:16 300 I
16 Sep 02:31:05 180 V
16 Sep 02:35:14 1200 V
----------------------------------
Additional images (I-band, 720-s) were also
taken at the 1.5m telescope at IAA Sierra
Nevada Observatory on 13 Sep (03:00 UT).
Internal comparison between the three V-band
frames did not reveal any optical variable
source in the entire HETE-2 error box. For
the 22 X-rays sources detected by the Chandra
X-ray Observatory (Butler et al., GCN Circ
2716) we detect the following optical
counterparts in the co-added V-band image
(3 sigma limiting magnitude = 25.1):
-------------------------------------
CXO V-band Distance to
source magnitude X-ray position (")
-------------------------------------
#1 21.6 2.0
#2 24.0 2.0
#3 21.1 2.0
#4 24.0 2.0
#5 21.9 1.4
#6 21.0 1.7
#7 22.9 1.7
#8 23.9 1.4
#9 23.9 1.8
#10 21.1 1.6
#11 23.0 1.4
#12 24.2 1.9
#13 23.6 0.5
#14* 23.9 0.9
22.7 1.8
#15 23.9 2.1
#16** >25.1 -
#17 24.5 2.0
#18 23.3 0.1
#19 >25.1 -
#20 >25.1 -
#21 >25.1 -
#22 >25.1 -
--------------------------------------
* Two possible counterparts
* V = 22.1 optical source at 3".5
--------------------------------------
Optical magnitudes are based on the calibration
provided by A. Henden (GCN Circ. 2720)."
This message can be quoted.
[GCN OPS NOTE (21sep04): The affiliation for
D. Martinez-Delgado from "AIP Potsdam" to
"MPIfA Heidelberg".]