K. A. Kretke, H. F. Levison, M. W. Buie, A. Morbidelli
Observations indicate that the gaseous circumstellar disks around young stars
vary significantly in size, ranging from tens to thousands of AU. Models of
planet formation depend critically upon the properties of these primordial
disks, yet in general it is impossible to connect an existing planetary system
with an observed disk. We present a method by which we can constrain the size
of our own protosolar nebula using the properties of the small body reservoirs
in the solar system. In standard planet formation theory, after Jupiter and
Saturn formed they scattered a significant number of remnant planetesimals into
highly eccentric orbits. In this paper, we show that if there had been a
massive, extended protoplanetary disk at that time, then the disk would have
excited Kozai oscillations in some of the scattered objects, driving them into
high-inclination (i > 50 deg), low-eccentricity orbits (q > 30 AU). The
dissipation of the gaseous disk would strand a subset of objects in these
high-inclination orbits; orbits that are stable on Gyr time scales. To date,
surveys have not detected any Kuiper Belt Objects with orbits consistent with
this dynamical mechanism. Using these non-detections by the Deep Ecliptic
Survey (DES) and the Palomar Distant Solar System Survey we are able to rule
out an extended gaseous protoplanetary disk (R_D > 80 AU) in our solar system
at the time of Jupiter's formation. Future deep all sky surveys such as the
Large Synoptic Survey Telescope (LSST) will all us to further constrain the
size of the protoplanetary disk.
View original:
http://arxiv.org/abs/1202.2343
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