Observing Pools

Dear 30m user,

due to the demanding weather requirements of many projects, IRAM offers the pooled observing mode at the 30m telescope, allowing to optimize observations in a flexible way. Pooled observations are offered since 2002 and have by proven to be a very successful mode of observations.

At present, we offer a heterodyne pool for observations using HERA and EMIR (pool managers: Claudia Marka and Pablo García). The continuum prototype cameras, GISMO and NIKA have been dismounted in March 2015. In October 2015, the new large field-of-view continuum camera NIKA2 has been successfully installed. Testing and commissioning has started.

For each observing period, the 30m scheduler, based on program committee recommendations, selects those proposals which profit most from participating in the pool or are otherwise well suited to be included. The principal investigators of the programs concerned are then contacted by the scheduler. We propose to pool the accepted projects together and schedule them in a few observing sessions of typically about 2 weeks length. Those projects will then be observed by observers from participating projects under the coordination and help of the pool managers and astronomers-of-duty.

From our experience, the chances of success of a program are higher if it is scheduled in a pool than in the traditional way of dedicated observing blocks. This is due to the flexibility of pooled observations with respect e.g. to the weather conditions. Participation is of additional interest for low-rated proposals which may otherwise not be scheduled. Pooled observations should be fairly simple and straightforward to observe, using the standard instrumentation. For this reason, polarisation measurements using XPOL, to give an example, are excluded from the pools.

Several aspects are taken into account when deciding which projects to observe at a given time inside the pool. Important criteria are the final rating of a project, the source visibility, weather conditions, and participation. The amount of precipitable water vapor (pwv) as given by the atmospheric opacity (e.g. measured by the 225GHz taumeter) is a decisive parameter for all pools. The stability of the atmosphere is an additional important parameter for the continuum pools, in particular when observing extended sources.

The heterodyne pool contains three queues, for  excellent, good, and average weather conditions.

    • The average weather (or backup) queue contains projects to be observed when pwv>5mm. This queues contains mainly 3mm E090 EMIR projects. 
    • The good weather queue contains projects to be observed when 2mm<pwv<5mm. This queue mainly contains 1mm E230 EMIR and HERA projects.
    • Since the winter semester 09/10, the heterodyne pool also contains an excellent weather queue. These are mostly E330 projects, but also a few other projects. These projects shall be given priority when pwv<2mm.

If you have been granted observing time at the 30m telescope and feel you need more information about the pooled sessions, please contact us. If you are interested to participate actively as an observer, i.e. actually go to the 30m to help observing, please communicate your interest. It is expected that all A-rated programs longer than 20 hours, excluding target-of-opportunity projects, send at least one experienced observer. Astronomers with little or no experience may participate and are welcome as additional observers. In any case, the typical stay at the telescope should be one week.

See you at the telescope!
Claudia, Carsten