Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Luminosity Spectrometer for the Zeus Experiment at HERA   The HERA luminosity upgrade is expected to generate two major problems in the
current method of luminosity determination which is based on counting
brehmsstrahlung photons: damage of the calorimeter monitor due to high primary
synchrotron radiation and large multiple event (pile-up) corrections. The
luminosity spectrometer presented in this talk, is a novel method that reduces
the impact of these problems in the luminosity measurement and is expected to
yield a total systematic uncertainty of 1.4%. The spectrometer counts
brehmsstrahlung photon conversions in the beam pipe exit window using two small
calorimeters (former ZEUS beam pipe calorimeters) symmetrically placed away
from the synchrotron radiation plane. The photon conversion rate is measured by
counting electron-positron (ep) coincidences in the calorimeters. The ep
acceptance is measured using a third calorimeter (6 meter tagger) which tags
the brehmsstrahlung electrons. The electron-positron pair is separated by a
small dipole magnet.

9
The categories of this paper are: nlin
1
The categories of this paper are: cs
6
The categories of this paper are: astro-ph
0
The categories of this paper are: hep-ph
25
The categories of this paper are: patt-sol
30
The categories of this paper are: q-alg
13
The categories of this paper are: quant-ph
5
The categories of this paper are: gr-qc
32
The categories of this paper are: atom-ph
14
The categories of this paper are: math-ph
16
The categories of this paper are: stat
3
The categories of this paper are: physics
21
The categories of this paper are: adap-org
29
The categories of this paper are: funct-an
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The categories of this paper are: nucl-ex
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The categories of this paper are: eess