THIS PAGE IS OUTDATED !!! (CK, 15.11.08)
Mambo Bolometers at IRAM-30m
Contents
Description
The Mambo-1 and Mambo-2 bolometers have been developed at the Max-Planck-Institut fur Radiostronomie in Bonn by the group of Ernst Kreysa: MAMBO's 37 channel array has been successfully used by many observers since the end of 1998. Winter 2001/2002 was the first season of the new MAMBO-2 version with 117 pixels. The 37 channel MAMBO is used at the 30 m telescope as a backup system now. Both systems work at 1.2 mm wavelength and have a He-3 fridge to operate the bolometers at a temperature of 300 mK.
Status
He-Refilling
When in use, Mambo1 or Mambo2 are currently refilled with He4 every 48 hours. This procedure takes about 4-5 hours. It can be used for heterodyne observations.
OnOff pixel
- Mambo1: pixel 1 is the most sensitive.
- Mambo2: pixel 20 is the most sensitive.
Dead/Noisy Pixels
Instabilities
- Acceleration problem:
Gradient noise: about 6 % of scans are affected (stat. between 20.03.2007 and 30.03.2007)
Observing modes
The bolometers have two basic modes of observations:
On-Off: flux measurement with a single pixel on a point-like source, using the wobbler switching.
Mapping: On-the-fly map using the wobbler switching. By default the on-the-fly scanning is along the azimuth direction together with the wobbler switching. It is now possible to rotate the wobbler with the scanning direction to get rotated map. The rotated angle is currently in the range [-60,60] degrees.
Data Reduction
The data from the bolometer observations are recorded in IMBfits format. The data can be reduced using the Mopsic program (<zylka@iram.fr>) which is part of the GILDAS package.
Technical Issues
Noise statistics: noise measurements from observations on about 9000 scans. We estimate the noise statistics and the detection probability.
Contact Persons
Pool Manager: S. Leon (<leon@iram.es>)
Bolometer Expert: A. Sievers (<sievers@iram.es>)
Mambo/Abba expertise: G. Siringo (<gsiringo@mpifr-bonn.mpg.de>)
Mopsic development: R. Zylka (<zylka@iram.fr>)
Useful Links
Mambo pool at the IRAM-30m.
Time estimator for the bolometers and heterodyne receivers.
AbsorberTests to find the different tests done with absorbers and the He-refilling date.