Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spectral Emission of Moving Atom   A renewed analysis of the H.E. Ives and G.R. Stilwell's experiment on moving
hydrogen canal rays (J. Opt. Soc. Am., 1938, v.28, 215) concludes that the
spectral emission of a moving atom exhibits always a redshift which informs not
the direction of the atom's motion. The conclusion is also evident from a
simple energy relation: atomic spectral radiation is emitted as an orbiting
electron consumes a portion of its internal energy on transiting to a
lower-energy state which however has in a moving atom an additional energy
gain; this results in a redshift in the emission frequency. Based on auxiliary
experimental information and a scheme for de Broglie particle formation, we
give a vigorous elucidation of the mechanism for deceleration radiation of
atomic electron; the corresponding prediction of the redshift is in complete
agreement with the Ives and Stilwell's experimental formula.

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The categories of this paper are: eess
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The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
8
The categories of this paper are: hep-ex
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The categories of this paper are: q-alg
4
The categories of this paper are: cond-mat
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The categories of this paper are: nucl-th
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The categories of this paper are: acc-phys
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The categories of this paper are: quant-ph
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The categories of this paper are: hep-th
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The categories of this paper are: adap-org
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The categories of this paper are: q-fin
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The categories of this paper are: comp-gas
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The categories of this paper are: stat
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The categories of this paper are: atom-ph
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The categories of this paper are: mtrl-th