Spectral-Line On-the-Fly (SL-OTF)
Observing at the IRAM 30m Telescope 

For details see the latest update of the SL-OTF ``cookbook'':
 IRAM 30-m Telescope: Spectral Line On-The-Fly Mapping
(version 2.1, updated February 1999; HTML and Postscript).

Example maps are shown below.

General Information about SL-OTF at the IRAM 30m

 

  • During Spectral-Line On-The-Fly observing (SL-OTF) the telescope beam moves across the source at a constant speed, while data are recorded (or ``dumped'') every 1 or 2 seconds, depending on the backends and number of frequency channels. Any scanning direction can be chosen and maps can be built up line by line. Individual lines can have any length; they can be preceded and/or followed by off-source reference measurements. This observing mode can achieve a better homogeneity of the data and a more efficient use of observing time.
  • Up to 4 receivers can be used simultaneously in the usual combinations.
  • The backends can be the filter banks and/or the autocorrelators.
  • Ute Lisenfeld at IRAM Granada (mailto: ute@iram.es) is the first local contact for help with SL-OTF observing. Other astronomers in the IRAM Granada group will also be glad to assist.
  • Send your comments about this WWW page and the SL-OTF cookbook to: Hans Ungerechts (mailto: ungerechts@iram.es) .

Go Back to Top

Examples of images taken with SL-OTF on the IRAM 30m

(H. Ungerechts et al.)

Go Back to Top