Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Lunar Occultation of MACHOs   Lunar occultation can be used to measure the proper motions of some of the
long time scale microlensing events, $t_{e} \gsim 70$ days, now being detected
toward the Galactic bulge. The long events are difficult to explain within the
context of standard models of the mass distribution and dynamics of the Galaxy.
Han & Gould (1995b) have suggested that they may be due to a kinematically cold
population near the Sun. To resolve the mass, distance, and velocity of
individual events and so to determine their nature, one must measure parallaxes
and proper motions. For long events, parallaxes can be often obtained from
ground-based measurements, but proper motions can only rarely be determined
using conventional methods. Lunar occultations are therefore key to the
understanding of the long events. We carry out realistic simulations to
estimate the uncertainty of these measurements and show that proper motions
could be measured for about one long event per year.

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The categories of this paper are: cmp-lg
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The categories of this paper are: chem-ph
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The categories of this paper are: cs
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The categories of this paper are: funct-an
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The categories of this paper are: q-alg
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The categories of this paper are: patt-sol
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The categories of this paper are: plasm-ph
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The categories of this paper are: stat
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The categories of this paper are: ao-sci
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The categories of this paper are: hep-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: dg-ga
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The categories of this paper are: atom-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: q-fin
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The categories of this paper are: comp-gas