# Hubble Space Telescope Ultraviolet Light Curves Reveal Interesting Properties of CC Sculptoris and RZ Leonis

## TL;DR

Ultraviolet observations from the Hubble Space Telescope reveal the spin properties of white dwarfs in two cataclysmic variables, identifying RZ Leo as a likely Intermediate Polar and analyzing temperature variations in CC Scl.

## Contribution

The study provides new UV light curves that detect white dwarf spin periods and temperature changes in RZ Leo and CC Scl, enhancing understanding of their accretion dynamics.

## Key findings

- RZ Leo exhibits a 220s spin period and a 110s harmonic, indicating an Intermediate Polar.
- CC Scl shows a 389s spin period visible even at quiescence.
- Spectral analysis reveals hotter temperatures during spin peaks, with multiple UV components.

## Abstract

Time-tag ultraviolet data obtained on the Hubble Space Telescope in 2013 reveal interesting variability related to the white dwarf spin in the two cataclysmic variables RZ Leo and CC Scl. RZ Leo shows a period at 220s and its harmonic at 110s, thus identifying it as a likely Intermediate Polar (IP). The spin signal is not visible in a short single night of ground based data in 2016, but the shorter exposures in that dataset indicate a possible partial eclipse. The much larger UV amplitude of the spin signal in the known IP CC Scl allows the spin of 389s, previously only seen at outburst, to be visible at quiescence. Spectra created from the peaks and troughs of the spin times indicate a hotter temperature of several thousand degrees during the peak phases, with multiple components contributing to the UV light.