# The Period Evolution of the Chemically Peculiar Star V473 Tau

## TL;DR

This study investigates the period evolution of the chemically peculiar star V473 Tau using over fifty years of data, revealing a slight decrease in its rotation period likely caused by magnetic braking and differential rotation.

## Contribution

First combined space-based and archival data to analyze the long-term period evolution of V473 Tau, providing new insights into its rotational behavior and underlying physical mechanisms.

## Key findings

- Rotation period is approximately 1.406829 days.
- Period is decreasing at about -0.11 seconds per year.
- The period change timescale suggests possible reversibility.

## Abstract

In this paper, the period evolution of the rotating chemically peculiar star V473\,Tau (A0Si, V = 7.26 mag) is investigated. Even though the star has been observed for more than fifty years, for the first time four consecutive years of space-based data covering between 2007 and 2010 is presented. The data is from the {\sl STEREO} satellite, and is combined with the archival results. The analysis shows that the rotation period of V473\,Tau is $1.406829(10)$ days, and has slightly decreased with the variation rate of -0.11(3)~s~yr$^{-1}$ over time. Also, the acceleration timescale of the star is found to be around $-1.11(63) \times 10^6$~yr, shorter than its main sequence lifetime ($9.26(1.25) \times 10^8$~yr). This indicates that the process of decrease in period might be reversible. On this basis, it can be suggested that V473\,Tau has a possible magnetic breaking and a differential rotation, which cause a variation in the movement of inertia, and hence the observed period change.