Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Atomic and molecular dynamics triggered by ultrashort light pulses on
  the atto- to picosecond time scale   Time-resolved investigations of ultrafast electronic and molecular dynamics
were not possible until recently. The typical time scale of these processes is
in the picosecond to attosecond realm. The tremendous technological progress in
recent years made it possible to generate ultrashort pulses, which can be used
to trigger, to watch, and to control atomic and molecular motion. This tutorial
focuses on experimental and theoretical advances which are used to study the
dynamics of electrons and molecules in the presence of ultrashort pulses. In
the first part, the rotational dynamics of molecules, which happens on
picosecond and femtosecond time scales, is reviewed. Well-aligned molecules are
particularly suitable for angle-dependent investigations like x-ray diffraction
or strong-field ionization experiments. In the second part, the ionization
dynamics of atoms is studied. The characteristic time scale lies, here, in the
attosecond to few-femtosecond regime. Although a one-particle picture has been
successfully applied to many processes, many-body effects do constantly occur.
After a broad overview of the main mechanisms and the most common tools in
attosecond physics, examples of many-body dynamics in the attosecond world
(e.g., in high-harmonic generation and attosecond transient absorption
spectroscopy) are discussed.

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The categories of this paper are: bayes-an
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The categories of this paper are: ao-sci
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The categories of this paper are: chem-ph
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The categories of this paper are: funct-an
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The categories of this paper are: solv-int
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The categories of this paper are: quant-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: hep-lat
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The categories of this paper are: math-ph
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The categories of this paper are: q-fin
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The categories of this paper are: econ
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The categories of this paper are: gr-qc
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The categories of this paper are: chao-dyn
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The categories of this paper are: patt-sol
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The categories of this paper are: atom-ph
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The categories of this paper are: cond-mat