Call for Observing Proposals on the Plateau de Bure Interferometer

Conditions for the next summer period

As every year, we plan to carry out extensive technical work during the summer semester, including the regular maintenance of the antennas. Further work will also be done on the reduction of the sun avoidance circle. During this period, regular scientific observations will therefore mostly be carried out with the five element array. We plan to start the maintenance at the latest by the end of May and to schedule the D configuration between June and October.

We strongly encourage observers to submit proposals that can be executed during summer operating conditions. To keep the procedure as simple as possible, we ask to focus on:

• observations requesting the use of the 2mm and 3mm receivers
• circumpolar sources or sources transiting at night between June and September,
• observations that qualify for the 5D, 6D, and 6C configurations

Proposal category

Proposals should be submitted for one of the four categories:

1.3MM:

Proposals that ask for 1.3mm data. 3mm receivers can be used for pointing and calibration purposes, but cannot provide any imaging. Proposals requesting the extended tuning range (256-267GHz) will be carried out on a ``best effort'' basis only during the summer semester.

2MM:

Proposals that ask for 2mm data. 3mm receivers can be used for pointing and calibration purposes, but cannot provide any imaging.

3MM:

Proposals that ask for 3mm data.

TIME FILLER:

Proposals that have to be considered as background projects to fill in periods where the atmospheric conditions do not allow mapping, to fill in gaps in the scheduling, or even to fill in periods when only a subset of the standard 5-antenna configurations will be available. These proposals will be carried out on a ``best effort'' basis only.

SPECIAL:

Exploratory proposals: proposals whose scientific interest justifies the attempt to use the PdB array beyond its guaranteed capabilities. This category includes for example non-standard frequencies for which the tuning cannot be guaranteed, non-standard configurations and more generally all non-standard observations. These proposals will be carried out on a ``best effort'' basis only.

The proposal category will have to be specified on the proposal cover sheet and should be carefully considered by proposers.

As for the 30-m telescope, please refer to the full Call for Proposals on the IRAM web pages http://www.iram.fr/GENERAL/Proposals_observing.htm.

ASTRO

The software ASTRO has been updated to reflect these receiver/correlator setup possibilities. Astronomers are urged to download the most recent version of GILDAS at ../IRAMFR/GILDAS/ to prepare their proposals.

The previous LINE command has been replaced by several new commands (see internal help; the following description applies to the current receiver system). The behavior of the LINE command can be changed by the SET PDBI 1995|2000|2006 command, that selects the PdBI frontend/backend status corresponding to years 1995 (old receivers, 500 MHz bandwidth), 2000 (580 MHz bandwidth), 2006 (new receivers and new IF processor, 1GHz bandwidth). Default is 2006:

• LINE: receiver tuning
• NARROW: selection of the narrow-band correlator inputs
• SPECTRAL: spectral correlator unit tuning
• PLOT: control of the plot parameters.

A typical session would be:

   ! choice of receiver tuning
   line xyz 230 lsb low 5500

   ! choice of the correlator windows
   narrow Q2 Q2             

   ! correlator unit #1, on entry 1
   spectral 1  20 520 /narrow 1   

   ! correlator unit #2, on entry 1
   spectral 2 320 260 /narrow 1   

   ! correlator unit #3, on entry 2
   spectral 3  40 666 /narrow 2   
   ...

Finally, we would like to stress again the importance of the quality of the observing proposal. The IRAM interferometer is a powerful, but complex instrument, and proposal preparation requires special care. Information is available in this call and at ../IRAMFR/PDB/docu.html. The IRAM staff can help in case of doubts if contacted well before the deadline. Note that the proposal should not only justify the scientific interest, but also the need for the Plateau de Bure Interferometer.

Jan Martin WINTERS