Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Single-Shot Electron Diffraction using a Cold Atom Electron Source   Cold atom electron sources are a promising alternative to traditional
photocathode sources for use in ultrafast electron diffraction due to greatly
reduced electron temperature at creation, and the potential for a corresponding
increase in brightness. Here we demonstrate single-shot, nanosecond electron
diffraction from monocrystalline gold using cold electron bunches generated in
a cold atom electron source. The diffraction patterns have sufficient signal to
allow registration of multiple single-shot images, generating an averaged image
with significantly higher signal-to-noise ratio than obtained with unregistered
averaging. Reflection high-energy electron diffraction (RHEED) was also
demonstrated, showing that cold atom electron sources may be useful in
resolving nanosecond dynamics of nanometre scale near-surface structures.

5
The categories of this paper are: gr-qc
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The categories of this paper are: math
4
The categories of this paper are: cond-mat
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
34
The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
21
The categories of this paper are: adap-org
20
The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th
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The categories of this paper are: stat
1
The categories of this paper are: cs
18
The categories of this paper are: econ
13
The categories of this paper are: quant-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: hep-lat