2006CBET..404....1N

J.-U. Ness and S. Starrfield, Arizona State University; G. Schwarz and K. Vanlandingham, West Chester University; R. M. Wagner, LBT Observatory; J. Lyke, Keck Observatory; C. E. Woodward, University of Minnesota; and D. K. Lynch, The Aerospace Corporation, report that SWIFT XRT observations of V723 Cas (N Cas 1995; IAUC 6213, 6214, 6221) were obtained on Jan. 31.27 UT. V723 Cas was detected in x-rays and exhibited a super-soft-source spectrum with a peak around 0.4 keV. The best derived black-body fit is for a temperature of 340000 K and N_H = 1.6 x 10**(21) cm**(-2). The flux was 7.8 x 10**(-13) erg/cm**2/s. This nova is too bright in x-rays to have returned to quiescence, and – given that it has been 11 years since discovery – V723 Cas sets the record for being in outburst longer than any nova observed in x-rays. The previous record holder was GQ Mus, which was observed by ROSAT to be turning off in x-rays nine years after discovery (Shanley et al. 1995, Ap.J. 438, L95). This detection supports the observations of coronal lines in the infrared (IAUC 7259) and suggests that further study at other wavelengths is warranted.