 Submillimeter APEX Bolometer Camera Bolometer Development Group Millimeter & Submillimeter Astronomy Group Max-Planck-Institut für Radioastronomie (MPIfR)
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Welcome to the official SABOCA website SABOCA ( Submillimeter APEX Bolometer Camera) is a multi-beam bolometric receiver developed by the Max-Planck-Institut für Radioastronomie (MPIfR) of Bonn SABOCA is a superconducting (TES) bolometer camera installed on the APEX telescope for operation in the 350 micron atmospheric window Cryogenics
The bolometer array
of SABOCA is designed to be operated at a temperature of about 300 mK.
This temperature is provided by a cryogenic system made of a cryostat,
using liquid nitrogen and liquid helium, in combination with a
close-cycle helium-3 sorption cooler.
 The cryostat of SABOCA (built by Infrared Labs) incorporates a 2-liter reservoir of liquid nitrogen and a 3-liter reservoir of liquid helium. After achieving high-vacuum insulation, the cryostat is filled with the liquid cryogens. A dry (scroll) pump, installed in the C-cabin, is used to reduce the vapor pressure on the liquid helium bath in order to lower the boiling point, reaching a temperature of about 1.6 K. This operation requires about 2 hours. The single stage helium-3 close-cycle sorption cooler is then operated to reach the bolometers operation temperature of about 300 mK. The cryostat needs to be refilled, pumped and recycled every 48 hours. The helium pumping system and the operation of the sorption cooler have been automated and remotely controlled, allowing operation of the telescope during the cool down process (about 3 hours). |
| web: gsiringo (at) mpifr-bonn.mpg.de | last edit: G. Siringo, MPIfR - February 2009 |