Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Megahertz-rate Ultrafast X-ray Scattering and Holographic Imaging at the
  European XFEL   The advent of X-ray free-electron lasers (XFELs) has revolutionized
fundamental science, from atomic to condensed matter physics, from chemistry to
biology, giving researchers access to X-rays with unprecedented brightness,
coherence, and pulse duration. All XFEL facilities built until recently
provided X-ray pulses at a relatively low repetition rate, with limited data
statistics. Here, we present the results from the first megahertz repetition
rate X-ray scattering experiments at the Spectroscopy and Coherent Scattering
(SCS) instrument of the European XFEL. We illustrate the experimental
capabilities that the SCS instrument offers, resulting from the operation at
MHz repetition rates and the availability of the novel DSSC 2D imaging
detector. Time-resolved magnetic X-ray scattering and holographic imaging
experiments in solid state samples were chosen as representative, providing an
ideal test-bed for operation at megahertz rates. Our results are relevant and
applicable to any other non-destructive XFEL experiments in the soft X-ray
range.

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The categories of this paper are: bayes-an
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The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
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The categories of this paper are: funct-an
1
The categories of this paper are: cs
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The categories of this paper are: stat
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The categories of this paper are: hep-lat
14
The categories of this paper are: math-ph
2
The categories of this paper are: math
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The categories of this paper are: cmp-lg
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The categories of this paper are: alg-geom
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The categories of this paper are: acc-phys
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The categories of this paper are: adap-org
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The categories of this paper are: econ
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The categories of this paper are: comp-gas