Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Tracing molecular dynamics at the femto-/atto-second boundary through
  extreme-ultraviolet pump-probe spectroscopy   Coherent light pulses of few to hundreds of femtoseconds (fs) duration have
prolifically served the field of ultrafast phenomena. While fs pulses address
mainly dynamics of nuclear motion in molecules or lattices in the gas, liquid
or condensed matter phase, the advent of attosecond pulses has in recent years
provided direct experimental access to ultrafast electron dynamics. However,
there are processes involving nuclear motion in molecules and in particular
coupled electronic and nuclear motion that possess few fs or even sub-fs
dynamics. In the present work we have succeeded in addressing simultaneously
vibrational and electronic dynamics in molecular Hydrogen. Utilizing a
broadband extreme-ultraviolet (XUV) continuum the entire, Frank-Condon allowed
spectrum of H2 is coherently excited. Vibrational, electronic and ionization
1fs scale dynamics are subsequently tracked by means of XUV-pump-XUV-probe
measurements. These reflect the intrinsic molecular behavior as the XUV probe
pulse hardly distorts the molecular potential.

14
The categories of this paper are: math-ph
12
The categories of this paper are: nucl-th
9
The categories of this paper are: nlin
30
The categories of this paper are: q-alg
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
29
The categories of this paper are: funct-an
18
The categories of this paper are: econ
34
The categories of this paper are: chem-ph
4
The categories of this paper are: cond-mat
17
The categories of this paper are: q-fin
36
The categories of this paper are: cmp-lg
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
22
The categories of this paper are: chao-dyn
15
The categories of this paper are: nucl-ex