Searching for a Hypervelocity White Dwarf Companion: A Proper Motion Survey of SN 1006

TL;DR

This study conducted a precise proper motion survey of the SN 1006 remnant to search for a hypervelocity white dwarf companion, testing a specific supernova progenitor model, and found no such object within detection limits.

Contribution

The paper provides the first deep, high-precision proper motion survey of SN 1006's interior, constraining the presence of a predicted hypervelocity white dwarf companion.

Findings

No high proper motion white dwarf detected within the remnant.

Rules out the existence of a companion with $V_{transverse} > 600$ km s$^{-1}$ and $L > 0.0176 L_\odot$.

Supports the absence of the specific D6 model companion in SN 1006.

Abstract

Type Ia Supernovae (SNe Ia) are securely understood to come from the thermonuclear explosion of a white dwarf as a result of binary interaction, but the nature of that binary interaction and the secondary object is uncertain. Recently, a double white dwarf model known as the dynamically driven double-degenerate double-detonation (D6) model has become a promising explanation for these events. One realization of this scenario predicts that the companion may survive the explosion and reside within the remnant as a fast moving ($V_{peculiar} >1000$ km s$^{-1}$), overluminous ($L > 0.1 L_\odot$) white dwarf. Recently, three objects which appear to have these unusual properties have been discovered in the Gaia survey. We obtained photometric observations of the SN Ia remnant SN 1006 with the Dark Energy Camera over four years to attempt to discover a similar star. We present a deep, high precision astrometric proper motion survey of the interior stellar population of the remnant. We rule out the existence of a high proper motion object consistent with our tested realization of the D6 scenario ($V_{transverse} > 600$ km s$^{-1}$ with $m_r < 21$ corresponding to an intrinsic luminosity of $L > 0.0176 L_\odot$). We conclude that such a star does not exist within the remnant, or is hidden from detection by either strong localized dust or the unlikely possibility of ejection from the binary system near parallel to the line of sight.