Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Coherent Electromagnetic Processes in Ultra-Peripheral Heavy-Ion
  Collisions   We report measurements for coherent rho^0 production, AuAu->AuAu rho^0, and
coherent rho^0 and e^+e^- pair production accompanied by mutual nuclear Coulomb
excitation, AuAu->Au*Au* rho^0 and AuAuee, in ultra-peripheral relativistic
gold-gold collisions (UPC). We discuss transverse momentum, mass, and rapidity
distributions. The two photon-process of e^+e^- pair production is an important
probe of strong field QED because of the large coupling Z*alpha=0.6. At
sqrt{s}=200GeV, the e^+e^- production cross section agrees with lowest order
QED calculations. The cross sections for coherent rho^0 production at
sqrt{s}=130 and 200GeV are in agreement with theoretical predictions. The
calculations for both, coherent e^+e^- and rho^0 production treat nuclear
excitation as independent process.

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The categories of this paper are: alg-geom
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The categories of this paper are: q-alg
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The categories of this paper are: chao-dyn
31
The categories of this paper are: ao-sci
33
The categories of this paper are: plasm-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: econ
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The categories of this paper are: eess
20
The categories of this paper are: acc-phys
0
The categories of this paper are: hep-ph
8
The categories of this paper are: hep-ex
6
The categories of this paper are: astro-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: chem-ph
1
The categories of this paper are: cs
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The categories of this paper are: nucl-th