No X-rays from the very nearby Type Ia SN2014J: constraints on its environment

TL;DR

Deep X-ray observations of SN2014J show no emission, constraining the progenitor's environment and ruling out certain single-degenerate models, favoring double-degenerate or specific unstable systems.

Contribution

This study provides the first stringent X-ray constraints on the environment of SN2014J, limiting progenitor mass-loss rates and ruling out steady mass-loss single-degenerate systems.

Findings

No X-ray emission detected down to L<7x10^{36} erg/s.

Progenitor mass-loss rate constrained to <10^{-9} M_sun/yr.

Rules out steady mass-loss single-degenerate progenitors.

Abstract

Deep X-ray observations of the post-explosion environment around the very nearby Type Ia SN\,2014J (Dl=3.5 Mpc) reveal no X-ray emission down to a luminosity L<7x10^{36} erg/s (0.3-10 keV) at t~20 days after the explosion. We interpret this limit in the context of Inverse Compton emission from upscattered optical photons by the supernova shock and constrain the pre-explosion mass-loss rate of the stellar progenitor system to be <10^{-9} M_sun yr-1 (for wind velocity v_w=100 km/s). Alternatively, the SN shock might be expanding into a uniform medium with density $n_CSM<3 cm-3. These results rule out single-degenerate (SD) systems with steady mass-loss until the terminal explosion and constrain the fraction of transferred material lost at the outer Lagrangian point to be <1%. The allowed progenitors are (i) WD-WD progenitors, (ii) SD systems with unstable hydrogen burning experiencing recurrent nova eruptions with recurrence time t<300 yrs and (iii) stars where the mass loss ceases before the explosion.