QPOs from post-shock accretion column of strongly magnetized accreting white dwarfs

TL;DR

This paper investigates the structure and dynamics of post-shock accretion columns in strongly magnetized white dwarfs, explaining observed quasi-periodic oscillations in optical light curves.

Contribution

It provides a detailed analysis of the accretion column structure and dynamics, linking theoretical models to observed QPOs in magnetic white dwarf systems.

Findings

Model explains high-frequency QPOs in polars

Accretion column dynamics match observed optical variability

Radiation processes in the post-shock region influence emission states

Abstract

An extended magnetosphere of a strongly magnetized accreting white dwarf (known as a polar) prevents the formation of an accretion disk and the matter is channelled to the magnetic pole(s). A few such sources show quasi-periodic oscillations in their optical light curves. These high-frequency oscillations are thought to be generated from the post-shock accretion column. The kinetic energy of the accretion flow is finally emitted from this post-shock region and the involved radiation processes decide the state of the matter. Here we study the structure and the dynamical properties of such accretion columns and compare the results with the observational characteristics.