IR counterpart candidates to the transient Swift J174535.5-285921 - UPDATE
ATel #3529; M. Servillat, J. Grindlay, P. Zhao, J. Hong, B. Allen (CfA), M. van den Berg (U. Utrecht), S. Laycock (UMass Lowell)
on 5 Aug 2011; 03:54 UT
Credential Certification: Mathieu Servillat (mservillat@cfa.harvard.edu)
Subjects: Infra-Red, X-ray, Binary, Black Hole, Neutron Star, Transient
Due to a correction of the coordinates (ATEL #3525) of the recent Galactic Center X-ray transient Swift J174535.5-285921 (ATEL #3472), we performed again the search for Ks-band near-infrared counterparts we reported in ATEL #3481 using images of the field we obtained with ISPI at CTIO 4m from 2005 to 2009, and 3 images obtained with PANIC at Magellan 6.5m (seeing 0.4-0.6") in 2004-06, 2007-08 and 2010-07 (the 2004 dataset is described in more detail by Laycock et al. 2005, ApJL, 634, L53).
We found no long-term variables aligned with the transient, and no astrometric candidates among our ISPI images. For the PANIC images, 2 candidates are consistent with the reported position of the transient Swift J174535.5-285921, and one to the matching Chandra X-ray source CXOGC J174535.6-285928 (Muno et al. 2009, ApJS, 181, 110).
IR CXOGC RA Dec K04 K07 K10
-- --------------- ------------ ------------ ----- ----- -----
S1 transient 17:45:35.774 -28:59:28.75 14.58 14.60 14.64
S2 transient 17:45:35.710 -28:59:29.71 15.06 15.14 15.32
S3 174535.6-285928 17:45:35.662 -28:59:28.99 14.57 14.56 14.68
Magnitudes are in the 2MASS system with an rms of ~0.2 mag, and absolute astrometry errors <0.2". Ks-band magnitudes are listed above for each star corresponding to the 3 PANIC observation epochs.
We provide finding charts with PANIC and ISPI images at the following link:
http://hea-www.harvard.edu/ChaMPlane/rapid_release.html
