Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dark Matter in the Cosmos - Its Direct Detection and the Role Of Nuclear
  Physics   Exotic dark matter together with dark energy or cosmological constant seem to
dominate in the Universe. An even higher density of such matter seems to be
gravitationally trapped in our Galaxy. The nature of dark matter can be
unveiled only, if it is detected in the laboratory. Thus the accomplishment of
this task is central to physics and cosmology. Current fashionable
supersymmetric models provide a natural dark matter candidate, which is the
lightest supersymmetric particle (LSP). Since the LSP is much heavier than the
proton, while its average energy is in the keV region, the most likely
possibility for its direct detection is via its elastic scattering with a
nuclear target. In order to evaluate the event rate one needs the nuclear
structure (form factor and/or spin response function) for the special nuclear
targets of experimental interest. Since the expected rates for
neutralino-nucleus scattering are expected to be small, one should exploit all
the characteristic signatures of this reaction. Such are: (i) In the standard
recoil measurements the modulation of the event rate due to the Earth's motion.
(ii) In directional recoil experiments the correlation of the event rate with
the sun's motion. One now has both modulation, which is much larger and depends
not only on time, but on the direction of observation as well, and a large
forward-backward asymmetry. (iii) In non recoil experiments gamma rays
following the decay of excited states populated during the Nucleus-LSP
collision. Branching ratios of about 6 percent are possible. (iv) novel
experiments in which one observes the electrons prodused during the collisionof
the LSP with the nucleus. Branching ratios of about 10 per cent are possible.

13
The categories of this paper are: quant-ph
29
The categories of this paper are: funct-an
27
The categories of this paper are: comp-gas
21
The categories of this paper are: adap-org
9
The categories of this paper are: nlin
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
28
The categories of this paper are: alg-geom
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
23
The categories of this paper are: solv-int
26
The categories of this paper are: bayes-an
32
The categories of this paper are: atom-ph
18
The categories of this paper are: econ