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We have revised the list of configurations to take into account
the advent of the 1.3 mm receivers and of the new stations.
The standard set includes four basic arrays built upon a primary set
of eight 4-antenna configurations (Table 1):
Table: Available configurations
The arrays, named AB, BC, CD and DD are reasonably suited for all
declinations (see Table 2).
- AB, made of A1, A2, B2, C1
This is the largest configuration, which
provides an angular resolution at 115 GHz ( at 230 GHz),
but offers little sensitivity to extended structures.
- BC, made of B1, B2, C1, C2
This is the standard high resolution mode.
- CD, made of C1, C2, D1
This is the standard low resolution mode. Beware that ``low'' resolution
is already at 230 GHz, however.
- DD, made of D1 and D2
This configuration has been created to provide ``very'' low resolution
at 230 GHz.
Mosaicing is usually done with CD or DD, but the combination
BC+D1 can also make sense for high resolution mosaics.
Lower spatial resolution projects will usually not be
considered, given the limited field of view of the IRAM interferometer.
The antenna beam size is at 100 GHz and the shortest possible
spacing is 24 m, to avoid collisions between two antennas. Even taking
into account projection effects that shorten the effective baseline,
sources larger than about are heavily resolved at 110 GHz.
Non imaging projects, such as detection experiments, size measurements,
snapshots, etc., should use a subset of the standard configurations.
This subset can either be specified by the observer, or left undefined
until final scheduling if any configuration is appropriate (a detection
experiment for example).
Table: Beam sizes (in arc seconds)
Stéphane GUILLOTEAU
Next: Computers
Up: Interferometer
Previous: High frequency resolution
Robert Lucas
Mon Sep 18 09:50:01 METDST 1995