Swift X-ray and UV observations of Nova Cyg 2014
ATel #6051; T. Nelson (Minnesota), K. Mukai (UMBC/GSFC), L. Chomiuk, J. Linford, T. Finzell (Michigan State), J. Sokoloski, J. Weston (Columbia), M. Rupen, A. Mioduszewski (NRAO)
on 7 Apr 2014; 21:25 UT
Credential Certification: Thomas Nelson (tnelson@physics.umn.edu)
Subjects: Ultra-Violet, X-ray, Nova
Referred to by ATel #: 6108
We report X-ray and ultraviolet observations of the recently discovered Nova Cyg 2014 (PNV J20214234+3103296) with the Swift satellite. The observations took place over the course of approx. 12 hours on 2014 April 03 and 04, 3 days after discovery.
No X-ray source is detected the position of the nova. The total XRT exposure time was 4117s. Correcting for bad pixels in the combined image, and using the Bayesian method outlined in Kraft, Burrows and Nousek (1991), we find a 3-sigma upper limit to the count rate in the 0.3-10 keV range of <0.002 cts/s. Assuming that the spectrum at early times is similar to other novae (i.e. a 5 keV thermal plasma absorbed by an total column density of 1e22 cm^-2), this count rate limit corresponds to a flux <1.2e-13 erg/s/cm^2 in the 0.3-10 keV range.
Nova Cyg 2014 is clearly detected in the UV images obtained with the UVOT instrument. The observations were carried out using the UVW1 and UVM2 filters (central wavelengths 2600 and 2246 Angstroms, respectively), and extracting source photons from a 5-arcsec radius circular aperture centered on the nova we measure the following magnitudes:
UVW1 13.51 +/- 0.04
UVM2 16.01 +/- 0.05 (1-sigma uncertainties)
AAVSO observations taken on the same night report V ~ 10.9 magnitudes. Further X-ray and radio observations are planned. The nova has continued to brighten in the optical since its discovery, and so we encourage continued ground-based monitoring.
Kraft, R. P., Burrows, D. N. & Nousek, J. A. 1991 ApJ 374, 344
