Resumption of mass accretion in RS Oph

Abstract

The latest outburst of the recurrent nova RS Oph occurred in 2006 February. Photometric data presented here show evidence of the resumption of optical flickering, indicating re-establishment of accretion by day 241 of the outburst. Magnitude variations of up to 0.32 mag in V-band and 0.14 mag in B on timescales of 600-7000 s are detected. Over the two week observational period we also detect a 0.5 mag decline in the mean brightness, from V~11.4 to V~11.9, and record B~12.9 mag. Limits on the mass accretion rate of ~10^{-10} to 10^{-9} Msun/yr are calculated, which span the range of accretion rates modeled for direct wind accretion and Roche lobe overflow mechanisms. The current accretion rates make it difficult for thermonuclear runaway models to explain the observed recurrence interval, and this implies average accretion rates are typically higher than seen immediately post-outburst.Comment: 5 pages, 5 figures, accepted for publication in MNRA

Optical spectroscopy of the recurrent nova RS Ophiuchi – from the outburst of 2006 to quiescence

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M31N 2008-12a—THE REMARKABLE RECURRENT NOVA IN M31: PANCHROMATIC OBSERVATIONS OF THE 2015 ERUPTION

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High Energy Emission of Symbiotic Recurrent Novae: RS Oph and V407 Cyg

“…An extremely large initial mass and a high accretion rate are required (see Hernanz & José 2008). Initial white dwarf mass should be larger than 1.35 M ⊙ and the mass accretion rate not smaller than 2 × 10 −7 M ⊙ yr −1 (see, e.g., Walder et al 2008 andWorters et al 2007 for some estimates of the expected accretion rate).…”