2013ApJ...778L..35M

Justham and Di Stefano et al. proposed that the white dwarf progenitor of a Type Ia supernova (SN Ia) may have to spin down before it can explode. As the white dwarf spin-down timescale is not well known theoretically, here we try to constrain it empirically (within the framework of this spin-down model) for progenitor systems that contain a giant donor and for which circumbinary material has been detected after the explosion: we obtain an upper limit of a few 10⁷yr. Based on the study of Di Stefano & Kilic, this means that it is too early to rule out the existence of a surviving companion in SNR 0509-67.5.