The Super-Soft X-ray Phase of Nova RS Ophiuchi 2006

Understand

Swift X-ray observations of the ~60 day super-soft phase of the recurrent nova RS Ophiuchi 2006 show the progress of nuclear burning on the white dwarf in exquisite detail.

• First seen 26 days after the optical outburst, this phase started with extreme variability likely due to variable absorption, although intrinsic white dwarf variations are not excluded.
• About 32 days later, a steady decline in count-rate set in.
• NLTE model atmosphere spectral fits during the super-soft phase show that the effective temperature of the white dwarf increases from ~65 eV to ~90 eV during the extreme variability phase, falling slowly after about day 60 and more rapidly after day 80.