Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The appearance of particle tracks in detectors -- II: the semi-classical
  realm   The appearance of tracks, close to classical orbits, left by charged quantum
particles propagating inside a detector, such as a cavity periodically
illuminated by light pulses, is studied for a family of idealized models. In
the semi-classical regime, which is reached when one considers highly energetic
particles, we present a detailed, mathematically rigorous analysis of this
phenomenon. If the Hamiltonian of the particles is quadratic in position- and
momentum operators, as in the examples of a freely moving particle or a
particle in a homogeneous external magnetic field, we show how symmetries, such
as spherical symmetry, of the initial state of a particle are broken by tracks
consisting of infinitely many approximately measured particle positions and
how, in the classical limit, the initial position and velocity of a classical
particle trajectory can be reconstructed from the observed particle track.

29
The categories of this paper are: funct-an
3
The categories of this paper are: physics
7
The categories of this paper are: hep-th
25
The categories of this paper are: patt-sol
26
The categories of this paper are: bayes-an
34
The categories of this paper are: chem-ph
33
The categories of this paper are: plasm-ph
8
The categories of this paper are: hep-ex
19
The categories of this paper are: eess
11
The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg
18
The categories of this paper are: econ
27
The categories of this paper are: comp-gas
16
The categories of this paper are: stat
32
The categories of this paper are: atom-ph
28
The categories of this paper are: alg-geom