Swift observations of the March 2011 outburst of the cataclysmic variable NSV 1436: a probable dwarf nova (Research Note)

TL;DR

This study used Swift satellite observations and AAVSO data to analyze the 2011 outburst of NSV 1436, concluding it was a dwarf nova with a likely orbital period under 2 hours.

Contribution

It provides the first detailed multi-wavelength characterization of NSV 1436's outburst, clarifying its classification as a dwarf nova rather than a recurrent nova.

Findings

Outburst coincided with faint, soft X-ray state

X-ray source was harder and brighter during decline

Optical fading suggests orbital period below 2 hours

Abstract

The March 2011 outburst of the poorly-studied cataclysmic variable NSV 1436 offered an opportunity to decide between dwarf nova and recurrent nova classifications. We use seven daily observations in the X-ray and UV by the Swift satellite, together with AAVSO V photometry, to characterise the outburst and decline behaviour. The short optical outburst coincided with a faint and relatively soft X-ray state, whereas in decline to fainter optical magnitudes the X-ray source was harder and brighter. These attributes, and the modest optical outburst amplitude, indicate that this was a dwarf nova outburst and not a recurrent nova. The rapid optical fading suggests an orbital period below 2 hours.