# A study of Variability of the Marginal Am star HD 176843 observed in the Kepler field

## TL;DR

This study investigates the variability of the marginal Am star HD 176843 using Kepler photometry and ground-based spectroscopy, revealing dominant pulsation modes, radial velocity variations, and an orbital period, with no clear binary motion detected.

## Contribution

It provides the first detailed analysis of HD 176843's pulsations and radial velocity variations, combining space-based and ground-based data to characterize its variability and orbital properties.

## Key findings

- Identified three dominant pulsation modes in HD 176843.
- Detected significant radial velocity variations indicating orbital motion.
- Found an orbital period of approximately 34.14 days without evidence of binary motion in photometry.

## Abstract

We present results of a study of the variability of the marginal Am star HD\,176843 observed in the {\it Kepler} field. {\it Kepler} photometry and ground-based spectroscopy are used to investigate the light variations of the star. HD\,176843 is classified as a marginal Am star that shows $\delta$\ Sct type pulsations. From an analysis of the {\it Kepler} time series, we find that the light curve of HD\,176843 is dominated by three modes with frequencies $f_{1}$=0.1145, $f_{2}$=0.0162 and $f_{3}$=0.1078 d$^{-1}$. The amplitude of the radial velocity variations of about 10 km/s is much more than the radial velocity errors and allows us to conclude clear radial velocity variations. Using the radial velocity data and the adopted spectra, the orbital solution of HD\,176843 is also obtained with an orbital period of 34.14 days. However, the available photometric data show no significant evidence for any possible motion in the binary system.