Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measurement of the Generalized Polarizabilities of the Proton at
  Intermediate $Q^2$   Background: Generalized polarizabilities (GPs) are important observables to
describe the nucleon structure, and measurements of these observables are still
scarce. Purpose: This paper presents details of a virtual Compton scattering
(VCS) experiment, performed at the A1 setup at the Mainz Microtron by studying
the $e p \to e p \gamma$ reaction. The article focuses on selected aspects of
the analysis. Method: The experiment extracted the $P_{LL} -P_{TT} / \epsilon$
and $P_{LT}$ structure functions, as well as the electric and magnetic GPs of
the proton, at three new values of the four-momentum transfer squared $Q^2$:
0.10, 0.20 and 0.45 GeV$^2$. Results: We emphasize the importance of the
calibration of experimental parameters. The behavior of the measured $e p \to e
p \gamma$ cross section is presented and compared to the theory. A detailed
investigation of the polarizability fits reveals part of their complexity, in
connection with the higher-order terms of the low-energy expansion.
Conclusions: The presented aspects are elements which contribute to minimize
the systematic uncertainties and improve the precision of the physics results.

36
The categories of this paper are: cmp-lg
2
The categories of this paper are: math
31
The categories of this paper are: ao-sci
13
The categories of this paper are: quant-ph
8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom
34
The categories of this paper are: chem-ph
14
The categories of this paper are: math-ph
4
The categories of this paper are: cond-mat
26
The categories of this paper are: bayes-an
18
The categories of this paper are: econ
7
The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
1
The categories of this paper are: cs
6
The categories of this paper are: astro-ph
25
The categories of this paper are: patt-sol