XMM-Newton localization of the fast x-ray transient XTE J1901+014
ATel #1268; David M. Smith, Rachel A. Rampy (UC Santa Cruz), Ignacio Negueruela, Jose Miguel Torrejon (U. Alicante)
on 9 Nov 2007; 22:38 UT
Credential Certification: David M. Smith (dsmith@ssl.berkeley.edu)
Subjects: Infra-Red, X-ray, Transient
XMM-Newton observed the fast transient source XTE J1901+014
(Remillard and Smith 2002, ATEL #88) on 2006 Oct 14. A source with
extremely rapid variability on minute timescales was found at RA = 19h
01m 40.20s, DEC = +01o 26' 26.0". This position is from the pipeline
analysis of the EPIC PN, with 1" rms expected accuracy (Kirsch et
al. 2004, SPIE 5488, 103). It is consistent with the position of
ROSAT source 1RXS J190141.0+012618. The fast variability is
consistent with earlier observations with RXTE/PCA (Karasev et
al. 2007, Ast. Lett. 33, 159).
The XMM-Newton position is
inconsistent with both stars considered as possible counterparts by
Karasev et al. (2007). A K-band image taken with the 3.5-m TNG (La
Palma) may show a very faint excess above the sky level consistent
with the XMM-Newton position. There is no visible counterpart in the H
or J images.
The nature of this system, with its very short
flares from millicrab to Crab levels, remains a mystery. The faint
showing in the K band rules out the possibility that this object is a
supergiant fast x-ray transient (SFXT) in our Galaxy.