An Analysis of X-Ray Hardness Ratios Between Asynchronous and Non-Asynchronous Polars

TL;DR

This study investigates whether asynchronous polars, a subtype of magnetic Cataclysmic Variables, have intrinsically harder X-ray spectra compared to synchronized polars, but finds no statistically significant difference.

Contribution

It provides the first comparative analysis of X-ray hardness ratios between asynchronous and non-asynchronous polars, exploring their spectral differences.

Findings

Asynchronous polars may have harder X-ray spectra.

No statistically significant spectral difference was found.

Supports further investigation into spectral properties of CV subtypes.

Abstract

The subclass of magnetic Cataclysmic Variables (CV), known as asynchronous polars, are still relatively poorly understood. An asynchronous polar is a polar in which the spin period of the white dwarf is either shorter or longer than the binary orbital period (typically within a few percent). The asynchronous polars have been disproportionately detected in soft gamma-ray observations, leading us to consider the possibility that they have intrinsically harder X-ray spectra. We compared standard and asynchronous polars in order to examine the relationship between a CV's synchronization status and its spectral shape. Using the entire sample of asynchronous polars, we find that the asynchronous polars may, indeed, have harder spectra, but that the result is not statistically significant.