Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Physics Backgrounds to Supersymmetric Signals with Two Photons and
  Missing Mass at LEP   We calculate the event rates for the Standard Model production of two photons
plus missing mass through the process electron positron to gamma gamma nu
nubar, where nu is any of the three neutrino flavors, at LEP energies. This
process can be a background to new physics signatures, such as that expected
from supersymmetry with a higgsino or gravitino LSP. The missing mass
distribution is presented for several sets of kinematic cuts at beam energies
of 161, 172, 184, and 194 GeV. The effect of initial state photon radiation is
also studied, and is found to be significant, approximately doubling the event
rates.

18
The categories of this paper are: econ
7
The categories of this paper are: hep-th
17
The categories of this paper are: q-fin
3
The categories of this paper are: physics
34
The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg
33
The categories of this paper are: plasm-ph
10
The categories of this paper are: q-bio
8
The categories of this paper are: hep-ex
12
The categories of this paper are: nucl-th
22
The categories of this paper are: chao-dyn
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The categories of this paper are: adap-org
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
25
The categories of this paper are: patt-sol
28
The categories of this paper are: alg-geom