Search for sub-kilometre trans-Neptunian objects using CoRoT asteroseismology data

• Published in: Monthly notices of the Royal Astronomical Society 2015-01, Vol.446 (1), p.932-940
• Main Authors: Liu, Chih-Yuan, Doressoundiram, Alain, Roques, Franoise, Chang, Hsiang-Kuang, Maquet, Lucie, Auvergne, Michel
• Format: Article
• Language: English
• Subjects: Astronomy; Astrophysics; Density; Deviation; Hubble Space Telescope; Physics; Searching; Seismology; Signal to noise ratio; Size distribution; Space telescopes; Stars & galaxies; Symbols; Trans-Neptunian objects; Transits
• ISSN: 0035-8711; 1365-2966
• DOI: 10.1093/mnras/stu1987

We present the search for sub-kilometre trans-Neptunian objects (TNOs) by re-examining the CoRoT (Convection Rotation and Planetary Transits) asteroseismology observations. The total observation time employed in this work is about 144 000 star hours with signal-to-noise ratio larger than 1000 computed on 30-s intervals. 13 Possible Occultation Events (POEs) were found from the deviation method. These detections gives a density in the ecliptic sky plane of TNOs larger than 400-m radius of $N(R > 400\,\mathrm{m})=1.4^{+4.2} _{-0.7} \times 10^{7}\,\mathrm{deg}^{-2}$ . The fit of the density of TNOs with the believed break r break = 45 km provides a power-law size distribution index q larger than 3.5. This value is consistent with the detection of two potential events from Hubble Space Telescope (HST)/Fine Guidance Sensor (FGS) observations that found q = 3.8 ± 0.2. However, fitting the 13 POEs with the HST/FGS result alone gives a power-law size distribution index of q = 4.5 ± 0.2 in the size range of 0.2–2.0 km. This value is then compared with evolution models of the Kuiper belt.