East Asian Meeting on Astronomy
Time: October 14-18, 2013
Place: Taipei, Taiwan

Poster Presentation

Discovery of a New Member of the Inner Oort Cloud from The Next Generation Virgo Cluster Survey

Ying-Tung Chen (NCU), J. J. Kavelaars (HIA), Stephen Gwyn (HIA), Laura Ferrarese (HIA), Patrick Cote (HIA), Andres Jordan (PUC de Chile), Vincent Suc (PUC de Chile), Jean-Charles Cuillandre (CFHT), and Wing-Huen Ip (NCU)

We report the discovery of 2010 GB174, a likely new member of the Inner Oort Cloud (IOC). 2010 GB174 is 1 of 91 trans Neptunian objects and Centaurs discovered in a 76 square degree contiguous region imaged as part of the Next Generation Virgo Cluster Survey (NGVS)—a moderate ecliptic latitude survey reaching a mean limiting magnitude of g′ ≃ 25.5—using MegaPrime on the 3.6 m Canada–France–Hawaii Telescope. 2010 GB174 is found to have an orbit with a semi-major axis of a ≃ 350.8 AU, an inclination of i ≃ 21.6, and a pericenter of q ∼ 48.5 AU. This is the second largest perihelion distance among known solar system objects. Based on the sky coverage and depth of the NGVS,we estimate the number of IOC members with sizes larger than 300km (H_V ≦ 6.2 mag) to be ≃ 11,000.
A comparison of the detection rate from the NGVS and the PDSSS (a characterized survey that “rediscovered” the IOC object Sedna) gives, for an assumed a power-law luminosity function for IOC objects, a slope of α ≃ 0.7 ± 0.2. With only two detections in this region this slope estimate is highly uncertain.