Invited Article: Millimeter-wave bolometer array receiver for the Atacama pathfinder experiment Sunyaev-Zel'dovich (APEX-SZ) instrument
Journal article, 2011
The Atacama pathfinder experiment Sunyaev-Zel'dovich (APEX-SZ) instrument is a millimeter-wave cryogenic receiver designed to observe galaxy clusters via the Sunyaev-Zel'dovich effect from the 12 m APEX telescope on the Atacama plateau in Chile. The receiver contains a focal plane of 280 superconducting transition-edge sensor (TES) bolometers instrumented with a frequency-domain multiplexed readout system. The bolometers are cooled to 280 mK via a three-stage helium sorption refrigerator and a mechanical pulse-tube cooler. Three warm mirrors, two 4 K lenses, and a horn array couple the TES bolometers to the telescope. APEX-SZ observes in a single frequency band at 150 GHz with 1' angular resolution and a 22' field-of-view, all well suited for cluster mapping. The APEX-SZ receiver has played a key role in the introduction of several new technologies including TES bolometers, the frequency-domain multiplexed readout, and the use of a pulse-tube cooler with bolometers. As a result of these new technologies, the instrument has a higher instantaneous sensitivity and covers a larger field-of-view than earlier generations of Sunyaev-Zel'dovich instruments. The TES bolometers have a median sensitivity of 890 mu K(CMB)root s (NEy of 3.5 x 10(-4) root s). We have also demonstrated upgraded detectors with improved sensitivity of 530 mu K(CMB) root s (NEy of 2.2 x 10(-4) root s). Since its commissioning in April 2007, APEX-SZ has been used to map 48 clusters. We describe the design of the receiver and its performance when installed on the APEX telescope.
frequency-domain analysis
bolometers
cryogenics
camera
electrothermal feedback
cosmology
millimetre wave
series array
225-ghz atmospheric opacity
fluctuations
receivers
sorption
temperature
clusters of galaxies
south-pole telescope
galaxy clusters
focal planes
cosmology telescope
wavelength
astronomical telescopes
Author
D. Schwan
P., Ade
K. Basu
A. N. Bender
F. Bertoldi
H. M. Cho
G. Chon
John Clarke
M. Dobbs
D. Ferrusca
R. Güsten
N. W. Halverson
W. L. Holzapfel
Cathy Horellou
Chalmers, Earth and Space Sciences, Radio Astronomy and Astrophysics
Daniel Johansson
Chalmers, Earth and Space Sciences, Radio Astronomy and Astrophysics
B. R. Johnson
J. Kennedy
Z. Kermish
R. Kneissl
T. Lanting
A. T. Lee
M. Lueker
J. Mehl
K. M. Menten
D. Muders
F. Pacaud
T. Plagge
C. L. Reichardt
P. L. Richards
R. Schaaf
P. Schilke
M. W. Sommer
H. Spieler
C. Tucker
A. Weiss
B. Westbrook
O. Zahn
P. Soc Photo Optical V. Bin F
Review of Scientific Instruments
0034-6748 (ISSN) 1089-7623 (eISSN)
Vol. 82 9 091301Subject Categories
Astronomy, Astrophysics and Cosmology
DOI
10.1063/1.3637460