Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Improved Crystal Method for Photon Beam Linear Polarization Measurement
  at High Energies   A method for photon linear polarization determination based on the
measurement of the asymmetry of pairs produced by polarized photons in single
crystals within the optimal intervals of pair particles energies is proposed.
In difference to the well known methods the asymmetry in this case is
essentially larger. The optimal orientation of crystal is found which provides
the maximal values for analyzing power and figure of merit as well as minimal
measurement time.

21
The categories of this paper are: adap-org
37
The categories of this paper are: supr-con
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
35
The categories of this paper are: mtrl-th
20
The categories of this paper are: acc-phys
4
The categories of this paper are: cond-mat
30
The categories of this paper are: q-alg
28
The categories of this paper are: alg-geom
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
7
The categories of this paper are: hep-th