Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Modification of the Doppler Effect due to the Helicity-Rotation Coupling   The helicity-rotation coupling and its current empirical basis are examined.
The modification of the Doppler effect due to the coupling of photon spin with
the rotation of the observer is considered in detail in connection with its
applications in the Doppler tracking of spacecraft. Further implications of
this coupling and the possibility of searching for it in the intensity response
of a rotating detector are briefly discussed.

18
The categories of this paper are: econ
14
The categories of this paper are: math-ph
22
The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
13
The categories of this paper are: quant-ph
36
The categories of this paper are: cmp-lg
28
The categories of this paper are: alg-geom
10
The categories of this paper are: q-bio
2
The categories of this paper are: math
21
The categories of this paper are: adap-org
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The categories of this paper are: eess
20
The categories of this paper are: acc-phys
7
The categories of this paper are: hep-th
15
The categories of this paper are: nucl-ex
27
The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci