Oscillations in Procyon A: First results from a multi-site campaign

TL;DR

This paper reports on a multi-site spectroscopic campaign to detect and analyze solar-like oscillations in Procyon A, aiming to clarify its evolutionary state through improved frequency resolution and reduced aliasing.

Contribution

It presents the first results from a coordinated multi-site observational campaign designed to accurately identify oscillation frequencies in Procyon A.

Findings

Detection of power excess in the star's oscillation spectrum

Improved frequency resolution from nearly 4 weeks of data

Reduction of aliasing effects through multi-site observations

Abstract

Procyon A is a bright F5IV star in a binary system. Although the distance, mass and angular diameter of this star are all known with high precision, the exact evolutionary state is still unclear. Evolutionary tracks with different ages and different mass fractions of hydrogen in the core pass, within the errors, through the observed position of Procyon A in the Hertzsprung-Russell diagram. For more than 15 years several different groups have studied the solar-like oscillations in Procyon A to determine its evolutionary state. Although several studies independently detected power excess in the periodogram, there is no agreement on the actual oscillation frequencies yet. This is probably due to either insufficient high-quality data (i.e., aliasing) or due to intrinsic properties of the star (i.e., short mode lifetimes). Now a spectroscopic multi-site campaign using 10 telescopes world-wide (minimizing aliasing effects) with a total time span of nearly 4 weeks (increase the frequency resolution) is performed to identify frequencies in this star and finally determine its properties and evolutionary state.