Solar-like oscillations in KIC11395018 and KIC11234888 from 8 months of Kepler data

TL;DR

This study analyzes eight months of Kepler data to detect and measure solar-like oscillations in two stars, providing insights into their internal structures and rotation, despite low signal-to-noise ratios.

Contribution

First detection and measurement of p-mode frequencies in KIC 11395018 and KIC 11234888 using Kepler data, demonstrating the potential of long-term observations for stellar characterization.

Findings

Detected 22 p-modes in KIC 11395018

Detected 16 p-modes in KIC 11234888

Estimated stellar parameters using scaling laws

Abstract

We analyze the photometric short-cadence data obtained with the Kepler Mission during the first eight months of observations of two solar-type stars of spectral types G and F: KIC 11395018 and KIC 11234888 respectively, the latter having a lower signal-to-noise ratio compared to the former. We estimate global parameters of the acoustic (p) modes such as the average large and small frequency separations, the frequency of the maximum of the p-mode envelope and the average linewidth of the acoustic modes. We were able to identify and to measure 22 p-mode frequencies for the first star and 16 for the second one even though the signal-to-noise ratios of these stars are rather low. We also derive some information about the stellar rotation periods from the analyses of the low-frequency parts of the power spectral densities. A model-independent estimation of the mean density, mass and radius are obtained using the scaling laws. We emphasize the importance of continued observations for the stars with low signal-to-noise ratio for an improved characterization of the oscillation modes. Our results offer a preview of what will be possible for many stars with the long data sets obtained during the remainder of the mission.