Infrared excesses in stars with and without planets using revised $WISE$ photometry

Abstract

We present an analysis on the potential prevalence of mid infrared excesses in stars with and without planetary companions. Based on an extended database of stars detected with the $WISE$ satellite, we studied two stellar samples: one with 236 planet hosts and another with 986 objects for which planets have been searched but not found. We determined the presence of an excess over the photosphere by comparing the observed flux ratio at 22 $\mu$m and 12 $\mu$m ($f_{22}/f_{12}$) with the corresponding synthetic value, derived from results of classical model photospheres. We found a detection rate of 0.85$\%$ at 22 $\mu$m (2 excesses) in the sample of stars with planets and 0.1$\%$ (1 detection) for the stars without planets. The difference of the detection rate between the two samples is not statistically significant, a result that is independent of the different approaches found in the literature to define an excess in the wavelength range covered by $WISE$ observations. As an additional result, we found that the $WISE$ fluxes required a normalisation procedure to make them compatible with synthetic data, probably pointing out a revision of the $WISE$ data calibration.

10 pages, 6 figures, 3 tables. Accepted for publication in MNRAS

References in corpus (10)

• A grid of MARCS model atmospheres for late-type stars I. Methods and general properties
• New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s). Improved astrophysical parameters for the Geneva-Copenhagen Survey
• Spectroscopic parameters for 451 stars in the HARPS GTO planet search program. Stellar [Fe/H] and the frequency of exo-Neptunes
• Debris disks around Sun-like stars
• Oxygen abundances in G- and F-type stars from HARPS
• Does the presence of planets affect the frequency and properties of extrasolar Kuiper Belts? Results from the Herschel DEBRIS and DUNES surveys
• Testing the Accuracy of Synthetic Stellar Libraries
• Disk Detective: Discovery of New Circumstellar Disk Candidates through Citizen Science
• The Frequency of Mid-Infrared Excess Sources in Galactic Surveys
• Extragalactic number counts at 100 um, free from cosmic variance