Faint-state transitions in the SW Sextantis nova-like variable, HS 0455+8315

TL;DR

This study presents a 14-year light curve of the nova-like variable HS 0455+8315, revealing two long faint states, and analyzes the star's brightness variations, eclipses, and flickering behavior during different states.

Contribution

It provides the first detailed long-term observational record of faint-state transitions in HS 0455+8315, highlighting the star's brightness decline and recovery patterns.

Findings

Two deep faint states lasted about 500 and 540 days.

Eclipses had similar profiles during normal and faint states.

Flickering persisted during all observed states.

Abstract

We present the fourteen year-long light curve of the SW Sextantis nova-like variable, HS 0455+8315, from 2000 November to 2015 February which reveals two deep faint states at magnitude 19 - 20, each of which lasted about 500 and 540 days. Outside these faint states, the star spent most of the time in a normal state at a magnitude of about 15.3. The second faint state was the better observed of the two and was found to have a linear decline of 0.009 mag/day, which was soon followed by a more rapid brightening at -0.020 mag/day. Time series photometry during both the normal state and near minimum light at about magnitude 18 showed that the eclipses had very similar profiles and that outside the eclipse there were irregular modulations typical of the flickering inherent to accreting CVs. Our photometry leading up to the minimum shows that accretion was still ongoing during this time.