# Statistical analysis of roAp, He-weak and He-rich stars

## TL;DR

This study expands the database of chemically peculiar stars, analyzing their physical parameters and abundance anomalies to identify correlations, with a focus on He-weak, He-rich, and roAp stars using statistical methods.

## Contribution

The paper provides an enlarged database of He-weak, He-rich, and roAp stars and offers new statistical insights into their physical parameters and abundance anomalies.

## Key findings

- Correlations between effective temperature and surface gravity across star types.
- Some correlations between projected rotation velocity and chemical peculiarities in He-rich stars.
- Inconclusive data on binary membership effects on chemical peculiarities.

## Abstract

To enlarge our database of Chemically Peculiar (CP) stars, we compiled published data concerning the He-weak and He-rich stars observed by high-resolution spectroscopy techniques during last decades. Twenty He-weak and 28 He-rich stars have been added to the database. We have also distinguished roAp stars from stars previously identified as Ap stars. To deepen our knowledge on statistical overview of the abundance anomalies versus the physical parameters of stars, we compared our data with previous compilations. We applied statistical tests on our data and found interesting correlations for effective temperature and surface gravity for all type of stars and a few correlations for projected rotation velocity only for He-rich stars. Because of the lack of the data we couldn't check whether being a member of binary system is affecting on chemical peculiarities of those stars.