A WISE view of IRAS debris disks: revising the dust properties

Debris disks around stars are considered as components of planetary systems. Constraining the dust properties of these disks can give crucial information to formation and evolution of planetary systems. As an all-sky survey, InfRared Astronomical Satellite (IRAS) gave great contribution to the debris disk searching which discovered the first debris disk host star (Vega). The IRAS-detected debris disk sample published by Rhee (Rhee et al. 2007) contains 146 stars with detailed information of dust properties. While the dust properties of 45 of them still cannot be determined due to the limitations with the IRAS database (have IRAS detection at 60 mu m only). Therefore, using more sensitivity data of Wide-field Infrared Survey Explorer (WISE), we can better characterize the sample stars: for the stars with IRAS detection at 60 mu m only, we refit the excessive flux densities and obtain the dust temperatures and fractional luminosities; while for the remaining stars with multi-bands IRAS detections, the dust properties are revised which show that the dust temperatures were overestimated in the high temperature band before. Moreover, we identify 17 stars with excesses at the WISE 22 mu m which have smaller distribution of distance from Earth and higher fractional luminosities than the other stars without mid-infrared excess emission. Among them, 15 stars can be found in previous works.

Automated summary

Debris disks around stars are important components of planetary systems and studying their dust properties can provide valuable information about the formation and evolution of planets. IRAS played a key role in discovering debris disk host stars, but limitations in the database require using WISE data for more accurate characterization. By using WISE data, the dust properties of sample stars were better characterized, revealing overestimated dust temperatures and identifying stars with mid-infrared excess emission.