Swift observes the XMM-Newton Slew Survey source XMMSL1 J171900.4-353217
ATel #2627; A M Read (Leicester), R D Saxton (ESAC), P Esquej (Leicester), P A Evans (Leicester)
on 19 May 2010; 11:57 UT
Credential Certification: Dr. Andy Read (amr30@star.le.ac.uk)
The hard X-ray source XMMSL1 J171900.4-353217, discovered by ESA's
XMM-Newton in its Slew Survey mode [ATel #2607] (also likely to be XTE
J1719-356 [ATel #2615]), has been observed by Swift on 11th May 2010
for 1.9 ksec.
The Swift-XRT position, enhanced by Swift-UVOT field astrometry, is
RA: 17 19 00.60 Dec: -35 32 19.4, with an error radius of 2.2
arcseconds (90% confidence). There are no catalogued objects in Vizier
within this error circle. There is no significant source visible at
this position in the Swift-UVOT uvw1 image.
The Swift-XRT X-ray spectrum can be fit by a power-law of photon index
2.03 (+0.37, -0.35) and column density 3.40 (+0.79, -0.69) E22 cm-2
(the Galactic column density in the direction of the source is 1.03E22
cm-2). The observed 0.2-10 keV flux in the Swift-XRT observation is
4.17 (+0.22, -0.25) E-11 ergs/s/cm^2, and the unabsorbed 0.2-10 keV
flux is 1.34E-10 ergs/s/cm^2. In the 2-10 keV band, the observed
Swift-XRT flux is 4.01 (+0.17, -0.13) E-11 ergs/s/cm^2, and the
unabsorbed flux is 5.34E-11 ergs/s/cm^2. This is consistent with the
flux observed in the XMM-Newton Slew. The Swift-XRT flux in the
0.2-2.4 keV band is a factor ~25 higher than the ROSAT All-Sky Survey
upper limit at this position.
The Swift-XRT lightcurve shows no significant variability in flux or
spectral hardness.
The source was not detected by INTEGRAL IBIS/ISGRI (9th-11th March
2010; [ATel #2616]). Extrapolating the Swift-XRT spectrum into the
INTEGRAL 20-40 keV band yields a flux (2.2E-11 ergs/s/cm^2)
approximately half that of the upper limit given in ATel #2616.
