January 2015 • 2015ApJ...798L..37F
Abstract • We present pre-explosion and post-explosion Hubble Space Telescope images of the Type Iax supernova (SN Iax) 2014dt in M61. After astrometrically aligning these images, we do not detect any stellar sources at the position of the SN in the pre-explosion images to relatively deep limits (3σ limits of M F438W > -5.0 mag and M F814W > -5.9 mag). These limits are similar to the luminosity of SN 2012Z's progenitor system (M F435W = -5.43 ± 0.15 and M F814W = -5.24 ± 0.16 mag), the only probable detected progenitor system in pre-explosion images of a SN Iax, and indeed, of any white-dwarf supernova. SN 2014dt is consistent with having a C/O white-dwarf primary/helium-star companion progenitor system, as was suggested for SN 2012Z, although perhaps with a slightly smaller or hotter donor. The data are also consistent with SN 2014dt having a low-mass red giant or main-sequence star companion. The data rule out main-sequence stars with M init >~ 16 M ⊙ and most evolved stars with M init >~ 8 M ⊙ as being the progenitor of SN 2014dt. Hot Wolf-Rayet stars are also allowed, but the lack of nearby bright sources makes this scenario unlikely. Because of its proximity (D = 12 Mpc), SN 2014dt is ideal for long-term monitoring, where images in ~2 yr may detect the companion star or the luminous bound remnant of the progenitor white dwarf.