Version 2 CARMA Configurations for Cedar Flat

Tamara T. Helfer
Radio Astronomy Lab, University of California, Berkeley


This report presents a revision of the Version 1 Cedar Flat CARMA
configurations given by Helfer & Wright in April 2003.  The 15-element
configurations in this report take into account specific characteristics
and limitations of the Cedar Flat site.  Here, a complete set of five
CARMA configurations is presented, with baselines as long as 1.9 km for A
array and as short as 8.3 m for the most compact E array.  The resolution
scale factor between adjacent arrays is 2.5 for all but the two most
compact arrays, where it is 2.0 (in order to allow for relatively short
baselines for the D array). A total of 60 stations is needed to populate
the five arrays. A corrected treatment of the issue of shadowing for the
compact arrays is also presented.  The orientation of the E array has been
optimized with regard to shadowing properties; furthermore, for this
array, the shadowing is nearly identical for the cases where the current
relative heights of the BIMA and OVRO elevation axes are preserved and
where the BIMA antennas are instead lowered by 0.5 m. The elevations of
all the proposed pads on the Cedar Site change by less than 50 m over the
2 km extent of the arrays, and the effect of the elevation differences on
the uv coverages and synthesized beams is trivial.