P51D-3975:
The IMACS Occultation Survey: I. Pilot Study
P51D-3975:
The IMACS Occultation Survey: I. Pilot Study
Friday, 19 December 2014
Abstract:
We report the results of a pilot study, searching for occultations ofbackground stars by small (sub-km) Kuiper belt objects (KBOs). Our
study is ground-based, using the Inamori Magellan Areal Camera and
Spectrograph (IMACS) instrument on the 6.5m Magellan Baade telescope,
at Las Campanas Observatory in Chile. We implemented a novel
shutterless continuous readout mode on the IMACS instrument, with
custom-made aperture masks, permitting simultaneous high-speed (36 Hz)
photometry for numerous stars, while minimizing the effects of stellar
crowding and sky background. Observing in the southern hemisphere
allows us to target the intersection of the ecliptic and galactic
planes, where hundreds of stars can be monitored with a single field
of view. We observed for a total of ~28 hours spread over eight
nights, obtaining ~11,000 star-hours of light curves with per-point
SNR > 10. This represents an order of magnitude increase in star-hours
compared to the previous best ground-based survey by Bianco et
al. (2009). Our results allow us to place strong constraints on the surface
density of sub-km objects in the Kuiper-Belt, as well as to complement the
HST FGS results of Schlichting et al. (2009, 2012).