Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: What Could the Machos Be?   If the Universe has a significant baryonic dark component in the form of
compact objects in galaxy halos (machos), then there is a minute chance (about
$10^{-7}$) that one of the Galactic machos passes sufficiently close to our
line of sight to a star out of some $10^7$ monitored stars in the Magellanic
Clouds (MCs) that it brightens by more than 0.3 magnitude due to gravitational
focusing. After a brief discussion of the current controversy over the
interpretation of the observed events, i.e., whether the lensing is caused by
halo white dwarfs or machos in general or by stars in various observed or
hypothesized structures of the Clouds and the Galaxy, I propose a few
observations to put ideas of the pro-macho camp and the pro-star camp to test.
In particular, I propose a radial velocity survey towards the MCs.

19
The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
12
The categories of this paper are: nucl-th
32
The categories of this paper are: atom-ph
23
The categories of this paper are: solv-int
10
The categories of this paper are: q-bio
4
The categories of this paper are: cond-mat
7
The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
34
The categories of this paper are: chem-ph
17
The categories of this paper are: q-fin
11
The categories of this paper are: hep-lat
3
The categories of this paper are: physics
21
The categories of this paper are: adap-org
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat