Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Reflectance of Rhenium as a Function of Pressure in a Diamond Anvil Cell   We have measured the reflectance of rhenium in the visible region to
pressures up to 100 GPa in a diamond anvil cell (DAC). By photographing the
reflecting surface, we visually show that there are challenges to obtaining
accurate values in a DAC for several reasons and propose some useful
procedures. We also show that knowledge of the reflectance of rhenium can
overcome the problem of absorption of light by diamonds when studying the
reflectance of materials at high pressure in a DAC.

19
The categories of this paper are: eess
14
The categories of this paper are: math-ph
11
The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg
35
The categories of this paper are: mtrl-th
18
The categories of this paper are: econ
27
The categories of this paper are: comp-gas
20
The categories of this paper are: acc-phys
3
The categories of this paper are: physics
0
The categories of this paper are: hep-ph
2
The categories of this paper are: math
12
The categories of this paper are: nucl-th
21
The categories of this paper are: adap-org
37
The categories of this paper are: supr-con
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The categories of this paper are: chao-dyn
15
The categories of this paper are: nucl-ex