Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Propagation of the photoelectron wave packet in an attosecond streaking
  experiment   Laser-assisted photoemission from a solid is considered within a numerically
exactly solvable one-dimensional model of a crystal. The effect of the
inelastic scattering and of the finite duration of the pump pulse on the
photoelectron dynamics is elucidated. The phenomenological result that the
photoexcited wave packet moves with the group velocity dE/dk and traverses on
average the distance equal to the mean free path is found to hold for energies
far from the spectral gaps of the final state band structure. On the contrary,
close to a spectral gap the photoelectron is found to move during the
excitation by the pump pulse with a velocity higher than the group velocity.

2
The categories of this paper are: math
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
27
The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
6
The categories of this paper are: astro-ph
24
The categories of this paper are: dg-ga
13
The categories of this paper are: quant-ph
19
The categories of this paper are: eess
12
The categories of this paper are: nucl-th
28
The categories of this paper are: alg-geom
9
The categories of this paper are: nlin
7
The categories of this paper are: hep-th
26
The categories of this paper are: bayes-an
30
The categories of this paper are: q-alg
33
The categories of this paper are: plasm-ph