Acoustic glitches in solar-type stars from Kepler

A. Mazumdar, M. J. P. F. G. Monteiro, J. Ballot, H. M. Antia, S. Basu, G. Houdek, S. Mathur, M. S. Cunha, V. Silva Aguirre, R. A. García, D. Salabert, G. A. Verner, J. Christensen-Dalsgaard, T. S. Metcalfe, W. J. Chaplin

Abstract
We report the measurement of the acoustic locations of layers of sharp variation in sound speed in the interiors of 19 solar-type stars observed by the Kepler mission. The oscillatory signal in the frequencies arising due to the acoustic glitches at the base of the convection zone and the second helium ionisation zone was utilised to determine their location by four independent methods. Despite the significantly different methods of analysis, remarkable agreement was found between the results of these four methods. Further, the extracted locations of these layers were found to be consistent with representative models of the stars.

Keywords
stars: interiors – stars: oscillations

Astronomische Nachrichten
Volume 333, Page 1040
December 2012

DOI: 10.1002/asna.201211825
ADS Bibliographic code: 2012AN....333.1040M