Warm debris disks candidates in transiting planets systems

Á. Ribas¹, B. Merín¹, D. R. Ardila² and H. Bouy³

¹ Herschel Science Centre, European Space Astronomy Centre (ESA), PO Box 78, 28691 Villanueva de la Cañada, Madrid, Spain
² NASA Herschel Science Center, California Institute of Technology, Mail Code 100-22, Pasadena, CA 91125, USA
³ Centro de Astrobiología, INTA-CSIC, PO Box – Apdo. de correos 78, 28691 Villanueva de la Cañada Madrid, Spain

Received: 20 October 2011
Accepted: 27 February 2012

Abstract

We have bandmerged candidate transiting planetary systems (from the Kepler satellite) and confirmed transiting planetary systems (from the literature) with the recent Wide-field Infrared Survey Explorer (WISE) preliminary release catalog. We have found 13 stars showing infrared excesses at either 12 μm and/or 22 μm. Without longer wavelength observations it is not possible to conclusively determine the nature of the excesses, although we argue that they are likely due to debris disks around the stars. If confirmed, our sample ~doubles the number of currently known warm excess disks around old main sequence stars. The ratios between the measured fluxes and the stellar photospheres are generally larger than expected for Gyr-old stars, such as these planetary hosts. Assuming temperature limits for the dust and emission from large dust particles, we derive estimates for the disk radii. These values are comparable to the planet’s semi-major axis, suggesting that the planets may be stirring the planetesimals in the system.