Faint warm debris disks around nearby bright stars explored by AKARI and IRSF

Abstract

Context: Debris disks are important observational clues for understanding planetary-system formation process. In particular, faint warm debris disks may be related to late planet formation near 1 AU. A systematic search of faint warm debris disks is necessary to reveal terrestrial planet formation. Aims: Faint warm debris disks show excess emission that peaks at mid-IR wavelengths. Thus we explore debris disks using the AKARI mid-IR all-sky point source catalog (PSC), a product of the second generation unbiased IR all-sky survey. Methods : We investigate IR excess emission for 678 isolated main-sequence stars for which there are 18 micron detections in the AKARI mid-IR all-sky catalog by comparing their fluxes with the predicted fluxes of the photospheres based on optical to near-IR fluxes and model spectra. The near-IR fluxes are first taken from the 2MASS PSC. However, 286 stars with Ks<4.5 in our sample have large flux errors in the 2MASS photometry due to saturation. Thus we have measured accurate J, H, and Ks band fluxes, applying neutral density (ND) filters for Simultaneous InfraRed Imager for Unbiased Survey (SIRIUS) on IRSF, the ϕ1.4 m near-IR telescope in South Africa, and improved the flux accuracy from 14% to 1.8% on average. Results: We identified 53 debris-disk candidates including eight new detections from our sample of 678 main-sequence stars. The detection rate of debris disks for this work is ~8%, which is comparable with those in previous works by Spitzer and Herschel. Conclusion: The importance of this study is the detection of faint warm debris disks around nearby field stars. At least nine objects have a large amount of dust for their ages, which cannot be explained by the conventional steady-state collisional cascade model.

17 pages, 21 figures, accepted for publication in Astronomy and Astrophysics

References in corpus (18)

• Debris Disk Evolution Around A Stars
• Transience of hot dust around sun-like stars
• Debris disks around Sun-like stars
• The Complete Census of 70-um-Bright Debris Disks within the FEPS (Formation and Evolution of Planetary Systems) Spitzer Legacy Survey of Sun-like Stars
• New Debris Disks Around Nearby Main Sequence Stars: Impact on The Direct Detection of Planets
• An Analysis of the Shapes of Interstellar Extinction Curves. VI. The Near-IR Extinction Law
• The History of the Solar System's Debris Disc: Observable Properties of the Kuiper Belt
• Large Impacts around a Solar Analog Star in the Era of Terrestrial Planet Formation
• Spitzer 24 Micron Observations of Open Cluster IC 2391 and Debris Disk Evolution of FGK Stars
• Does the presence of planets affect the frequency and properties of extrasolar Kuiper Belts? Results from the Herschel DEBRIS and DUNES surveys
• Warm Debris Disks Produced by Giant Impacts During Terrestrial Planet Formation
• A Sensitive Identification of Warm Debris Disks in the Solar Neighborhood Through Precise Calibration of Saturated WISE Photometry
• Variability of the Infrared Excess of Extreme Debris Disks
• On the Relationship Between Debris Disks and Planets
• Debris disc formation induced by planetary growth
• Modeling of the zodiacal emission for the AKARI/IRC mid-infrared all-sky diffuse maps
• Hot debris dust around HD 106797
• Herschel/PACS photometry of transiting-planet host stars with candidate warm debris disks

Cited by in corpus (8)

• Detection of submillimeter-wave [C I] emission in gaseous debris disks of 49 Ceti and Beta Pictoris
• Does warm debris dust stem from asteroid belts?
• Unbiased large spectroscopic surveys of galaxies selected by SPICA using dust bands
• A catalog of collected debris disks: properties, classifications and correlations between disks and stars/planets
• The Statistics of Extended Debris Disks Measured with Gaia and Planck
• Takeout and Delivery: Erasing the Dusty Signature of Late-stage Terrestrial Planet Formation
• A WISE View of IRAS Debris Disks: Revising the Dust Properties
• HD 44892: The youngest (or oldest?) gas-harbouring debris disc around an intermediate mass star