Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Matrix-element induced spin polarization of photoelectrons from bulk
  bands   Angular- or $k$-resolved photoelectron spectroscopy in the soft X-ray range
gives access to the bulk electronic structure of materials. Here this technique
is extended to the spin degree of freedom. A non-magnetic material (tungsten)
was chosen, in order to exclude any initial-state spin polarization from
exchange-split bands. By measurement of two spin-polarizations for different
light helicity, one can distinguish between contributions of optical
spin-orientation by circularly-polarized X-rays (Fano componen) and a second
component originating from interference of final-state partial waves. Both
phenomena have so far only been observed at low photon energies. Their
detection in the X-ray range is a milestone on the way to the "complete
experiment" in bulk photoemission.

9
The categories of this paper are: nlin
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The categories of this paper are: q-bio
11
The categories of this paper are: hep-lat
26
The categories of this paper are: bayes-an
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The categories of this paper are: stat
34
The categories of this paper are: chem-ph
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The categories of this paper are: econ
6
The categories of this paper are: astro-ph
15
The categories of this paper are: nucl-ex
0
The categories of this paper are: hep-ph
32
The categories of this paper are: atom-ph
7
The categories of this paper are: hep-th
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The categories of this paper are: eess
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The categories of this paper are: hep-ex
31
The categories of this paper are: ao-sci
24
The categories of this paper are: dg-ga