Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Atacama Cosmology Telescope: The Receiver and Instrumentation   The Atacama Cosmology Telescope was designed to measure small-scale
anisotropies in the Cosmic Microwave Background and detect galaxy clusters
through the Sunyaev-Zel'dovich effect. The instrument is located on Cerro Toco
in the Atacama Desert, at an altitude of 5190 meters. A six-meter off-axis
Gregorian telescope feeds a new type of cryogenic receiver, the Millimeter
Bolometer Array Camera. The receiver features three 1000-element arrays of
transition-edge sensor bolometers for observations at 148 GHz, 218 GHz, and 277
GHz. Each detector array is fed by free space mm-wave optics. Each frequency
band has a field of view of approximately 22' x 26'. The telescope was
commissioned in 2007 and has completed its third year of operations. We discuss
the major components of the telescope, camera, and related systems, and
summarize the instrument performance.

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The categories of this paper are: hep-lat
29
The categories of this paper are: funct-an
28
The categories of this paper are: alg-geom
0
The categories of this paper are: hep-ph
31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
21
The categories of this paper are: adap-org
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The categories of this paper are: stat
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The categories of this paper are: nlin
1
The categories of this paper are: cs
30
The categories of this paper are: q-alg
36
The categories of this paper are: cmp-lg
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The categories of this paper are: mtrl-th
4
The categories of this paper are: cond-mat
25
The categories of this paper are: patt-sol
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The categories of this paper are: eess