Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Accurate retrieval of structural information from laser-induced
  photoelectron and high-harmonic spectra by few-cycle laser pulses   By analyzing ``exact'' theoretical results from solving the time-dependent
Schr\"odinger equation of atoms in few-cycle laser pulses, we established the
general conclusion that differential elastic scattering and photo-recombination
cross sections of the target ion with {\em free} electrons can be extracted
accurately from laser-generated high-energy electron momentum spectra and
high-order harmonic spectra, respectively. Since both electron scattering and
photoionization (the inverse of photo-recombination) are the conventional means
for interrogating the structure of atoms and molecules, this result shows that
existing few-cycle infrared lasers can be implemented for ultrafast imaging of
transient molecules with temporal resolution of a few femtoseconds.

17
The categories of this paper are: q-fin
20
The categories of this paper are: acc-phys
12
The categories of this paper are: nucl-th
31
The categories of this paper are: ao-sci
0
The categories of this paper are: hep-ph
34
The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat
18
The categories of this paper are: econ
16
The categories of this paper are: stat
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
4
The categories of this paper are: cond-mat
6
The categories of this paper are: astro-ph
32
The categories of this paper are: atom-ph
1
The categories of this paper are: cs
19
The categories of this paper are: eess