Modelling the recurrent nova U Scorpii in quiescence

TL;DR

This study uses spectroscopic observations to analyze the reformation of the accretion disc in U Scorpii during quiescence, providing insights into the system's recovery process after outburst.

Contribution

It offers the first detailed spectroscopic evidence of the accretion disc reformation timeline in U Sco post-outburst and constrains the companion star's spectral class.

Findings

Accretion disc takes at least 18 months to fully reform.

Companion star's spectral class is constrained to F8^{+5}_{-6} IV-V.

Spectroscopic data reveal the system's recovery process during quiescence.

Abstract

VLT and SALT spectroscopy of U Sco were obtained $\sim$18 and $\sim$30 months after the 2010 outburst. From these spectra the accretion disc is shown to take at least 18 months to become fully reformed. The spectral class of the companion is constrained to be F8$^{+5}_{-6}$\,IV-V at the 95% confidence level when the irradiated face of the companion is visible.