Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Ionization behavior of molecular hydrogen in intense laser fields:
  Influence of molecular vibration and alignment   The alignment- and internuclear-distance dependent ionization of H$_2$
exposed to intense, ultrashort laser fields is studied by solving the
time-dependent two-electron Schr\"odinger equation. In the regime of
perturbative few-photon ionization, a strong dependence of the ionization yield
on the internuclear distance is found. While this finding confirms a previously
reported breakdown of the fixed-nuclei approximation for parallel alignment, a
simpler explanation is provided and it is demonstrated that this breakdown is
not due to vibrational dynamics during the laser pulse. The persistence of this
effect even for randomly aligned molecules is demonstrated. Furthermore, the
transition from the multiphoton to the quasi-static (tunneling) regime is
investigated considering intense 800 nm laser pulses. While the obtained
ionization yields differ significantly from the prediction of
Ammosov-Delone-Krainov rates, we find a surprisingly good quantitative
agreement after introducing a simple frequency-dependent correction to the
standard tunneling formula.

28
The categories of this paper are: alg-geom
25
The categories of this paper are: patt-sol
22
The categories of this paper are: chao-dyn
33
The categories of this paper are: plasm-ph
11
The categories of this paper are: hep-lat
17
The categories of this paper are: q-fin
27
The categories of this paper are: comp-gas
23
The categories of this paper are: solv-int
21
The categories of this paper are: adap-org
6
The categories of this paper are: astro-ph
7
The categories of this paper are: hep-th
26
The categories of this paper are: bayes-an
20
The categories of this paper are: acc-phys
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph
2
The categories of this paper are: math