Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The role of spin and angular momentum in strong-field ionization   The spin polarization of electrons from multiphoton ionization of Xe by 395
nm circularly polarized laser pulses at $6\cdot10^{13}$ W/cm$^2$ has been
measured. At this photon energy of 3.14 eV the above threshold ionization peaks
connected to Xe$^+$ ions in the ground state ($J=3/2$, ionization potential
$I_p=12.1$ eV) and the first exicted state ($J=1/2$, $I_p=13.4$ eV) are clearly
separated in the electron energy distribution. These two combs of ATI peaks
show opposite spin polarizations. The magnitude of the spin polarization is a
factor of two higher for the $J=1/2$ than for the $J=3/2$ final ionic state. In
turn the data show that the ionization probability is strongly dependent on the
sign of the magnetic quantum number.

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The categories of this paper are: astro-ph
21
The categories of this paper are: adap-org
33
The categories of this paper are: plasm-ph
26
The categories of this paper are: bayes-an
27
The categories of this paper are: comp-gas
16
The categories of this paper are: stat
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
11
The categories of this paper are: hep-lat
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The categories of this paper are: nucl-ex
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The categories of this paper are: math-ph
24
The categories of this paper are: dg-ga
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The categories of this paper are: nlin
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The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
13
The categories of this paper are: quant-ph