Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dielectric Coatings for IACT Mirrors   Imaging Atmospheric Cherenkov Telescopes for very-high energy gamma-ray
astronomy need mirror with high reflectance roughly in the wavelength between
300 and 550 nm. The current standard reflective layer of such mirrors is
aluminum. Being permanently exposed to the environment they show a constant
degradation over the years. New and improved dielectric coatings have been
developed to enhance their resistance to environmental impact and to extend
their possible lifetime. In addition, these customized coatings have an
increased reflectance of over 95% and are designed to significantly lower the
night-sky background contribution. The development of such coatings for mirrors
with areas up to 2 m2 and low application temperatures to suite the composite
materials used for the new mirror susbtrates of the Cherenkov Telescope Array
(CTA) and the results of extensive durability tests are presented.

29
The categories of this paper are: funct-an
7
The categories of this paper are: hep-th
32
The categories of this paper are: atom-ph
33
The categories of this paper are: plasm-ph
2
The categories of this paper are: math
21
The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph
35
The categories of this paper are: mtrl-th
11
The categories of this paper are: hep-lat
24
The categories of this paper are: dg-ga
15
The categories of this paper are: nucl-ex
9
The categories of this paper are: nlin
22
The categories of this paper are: chao-dyn
28
The categories of this paper are: alg-geom
0
The categories of this paper are: hep-ph
8
The categories of this paper are: hep-ex