Nova V1281 Sco now a bright SSS
ATel #1370; J. U. Ness and S. Starrfield (Arizona State), G. Schwarz (West Chester), M. F. Bode (Liverpool), J. P. Osborne and K. L. Page (Leicester)
on 25 Jan 2008; 16:32 UT
Distributed as an Instant Email Notice Novae
Credential Certification: Jan-Uwe Ness (Jan-Uwe.Ness@asu.edu)
Subjects: Ultra-Violet, X-ray, Cataclysmic Variable, Nova
On behalf of the Swift nova-cv group, we report the detection of a bright SSS X-ray spectrum for Nova V1281 Sco (discovered on 2007, Feb. 19.85) with the Swift XRT instrument (0.25-10 keV) on Jan. 24.18, 2008. The average count rate was 0.15ñ0.01 cps over the 5.24 ks observation. The spectrum peaks at 0.5 keV and can be fitted with an absorbed blackbody with parameters T=5x10 K and NH=8x10
cm. However, there is a suggestion of emission lines of NVI and NVII at 0.45 and 0.50 keV, respectively, which indicates a more complicated spectrum. The only previous Swift/XRT observation was three days after discovery (ATel 1011), and we obtain an upper limit of 0.001 cps. We also inspected the Swift UV filter images of the V1281 Sco field obtained with the UVOT instrument. V1281 Sco was not detected in either the UVM2 (231nm) or the UVW1 (291nm) filters, consistent with the large extinction previously reported (IAUC 8846 ). There was a detection in the shorter wavelength UVW2 band (212nm) at 19.110ñ0.059 magnitude. This corresponds to a flux of (1.22ñ0.07)10 erg scm Ã⦠which may be due to strong C III] (191nm) emission.