R. Musci, R. J. Weryk, P. Brown, M. D. Campbell-Brown, P. A. Wiegert
We report high resolution multi-station observations of meteors by the
Canadian Automated Meteor Observatory (CAMO) recorded from June 2009 to August
2010. Our survey has a limiting detection magnitude of +5 mag in R-band,
equivalent to a limiting meteoroid mass of ~2*E-7 kg. The high metric
trajectory accuracy (of the order of 30 m perpendicular to the solution and 200
m along-track) allows us to determine velocities with average uncertainty of <
1.5% in speed and ~0.4 degr in radiant direction. A total of 1739 meteors had
measured orbits. The data has been searched for meteors in hyperbolic orbits,
which are potentially of interstellar origin. We found 22 potential hyperbolic
meteors among our sample, with only two of them having a speed at least three
sigma above the hyperbolic limit. For our one year survey we find no clear
evidence of interstellar meteoroids at mm-sizes in a weighted time-area product
of ~1*E4 km^2*h. Backward integrations performed for these 22 potentially
hyperbolic meteors to check for close encounters with planets show no
considerable changes in their orbits. Detailed examination leads us to conclude
that our few identified events are most likely the result of measurement error.
We find an upper limit of f_ISP < 2*E-4/(km^2*h) for the flux of interstellar
meteoroids at Earth with a limiting mass of m > 2*E-7 kg.
View original:
http://arxiv.org/abs/1110.5882
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