# Six new rapidly oscillating Ap stars in the Kepler long-cadence data using super-Nyquist asteroseismology

## TL;DR

This study identifies six new rapidly oscillating Ap stars in Kepler data using super-Nyquist asteroseismology, revealing their pulsation modes, rotation periods, and magnetic characteristics, thus expanding understanding of stellar oscillations.

## Contribution

The paper introduces a novel application of super-Nyquist asteroseismology to detect rapidly oscillating Ap stars in Kepler data, identifying six new such stars and analyzing their pulsation properties.

## Key findings

- Six new rapidly oscillating Ap stars identified.
- Some stars oscillate above their acoustic cutoff frequency.
- Most stars show amplitude modulation consistent with oblique pulsator model.

## Abstract

We perform a search for rapidly oscillating Ap stars in the Kepler long-cadence data, where true oscillations above the Nyquist limit of 283.21 {\mu}Hz can be reliably distinguished from aliases as a consequence of the barycentric time corrections applied to the Kepler data. We find evidence for rapid oscillations in six stars: KIC 6631188, KIC 7018170, KIC 10685175, KIC 11031749, KIC 11296437 and KIC 11409673, and identify each star as chemically peculiar through either pre-existing classifications or spectroscopic measurements. For each star, we identify the principal pulsation mode, and are able to observe several additional pulsation modes in KIC 7018170. We find that KIC 7018170 and KIC 11409673 both oscillate above their theoretical acoustic cutoff frequency, whilst KIC 11031749 oscillates at the cutoff frequency within uncertainty. All but KIC 11031749 exhibit strong amplitude modulation consistent with the oblique pulsator model, confirming their mode geometry and periods of rotation.