Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: X-ray and $\gamma$-ray propagation in bent crystals with flat and
  cylindrical surfaces   In this paper we investigate x-ray and $\gamma$-ray propagation in crystals
having a constant strain gradient and flat or cylindrical surfaces. When a
displacement field is present, we solve the Takagi-Taupin equations either by
the Riemann-Green method or by a numerical method. We apply the results to
study the operation of a double-crystal Laue-Laue diffractometer having a flat
collimating crystal followed by a bent analyzer crystal. In particular, we
examine the effect of the analyzer strain on the location of the diffraction
peaks in the dispersive and non-dispersive setup, thus confirming our
previously reported peak-location as being set only by the diffracting plane
spacing on the analyzer entrance surface.

25
The categories of this paper are: patt-sol
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
1
The categories of this paper are: cs
35
The categories of this paper are: mtrl-th
28
The categories of this paper are: alg-geom
13
The categories of this paper are: quant-ph
24
The categories of this paper are: dg-ga
20
The categories of this paper are: acc-phys
2
The categories of this paper are: math
15
The categories of this paper are: nucl-ex
10
The categories of this paper are: q-bio
12
The categories of this paper are: nucl-th
14
The categories of this paper are: math-ph
7
The categories of this paper are: hep-th
23
The categories of this paper are: solv-int