A joint meeting of the U.S. MMA group and the European LSA group was held in Charlottesville March 6 and 7. The meeting included the MMA Division Heads together with a representive of the MDC on the U.S. side and the Heads of the LSA Working Groups on the European side. The LSA representatives included the following people:

Peter Shaver (ESO; Management)

Michael Grewing (IRAM; Management)

Roy Booth (Onsala; Management, Site)

Francois Viallefond (Meudon; Array Configuration)

Richard Hills (Cambridge; Antenna)

Stephane Guilloteau (IRAM; Software)

Peter Schilke (MPIfR; Calibration)

Robert Lucas (IRAM; System)

Richard Kurz (ESO; Project Engineering).

The purpose of the workshop was to initiate common technical planning that will facilitate a merger of the MMA and LSA projects should such a merger become a reality. At the moment the two groups are working independently on parallel efforts that will need to be brought to a convergence at the point in time that it is agreed to merge the LSA and MMA projects into a common US-European array. The workshop was an attempt to:

1. Avoid misunderstandings by making each group aware of what the other group is doing;
2. Identify incompatible efforts that will need resolution or redundant effort in the event a merger is possible;
3. Seek to identify technical areas in which work can be done cooperatively if not now collaboratively.

Presentations were made by each group in the areas of array system design, receiver development plans, antenna design, local oscillator options and requirements and on a variety of topics related to science requirements including configuration design, calibration techniques, and frequency coverage.

The group identified several areas in which joint studies can be done immediately with benefits to both groups. Foremost among these are software issues including discussions of the software goals appropriate to the array, discussion of observing and calibration techniques, and surveys of the capabilities of existing software systems. Other areas can profitably be explored separately by the two groups with periodic meetings to discuss intermediate results. These areas include receiver design and local oscillator design where choices between alternatives are better made by comparison of hardware prototypes, not by comparison of paper designs.

The antenna design presented a unique challenge. The needs of the MMA group are to proceed expeditiously to construction and evaluation of a prototype antenna that could, in principle, be the basis for a stand-alone array should the partnership initiative with the LSA fail. Given the amount of funding from the NSF alone, and the scientific requirements of the MMA for precision imaging, an antenna of diameter no larger than 10m can be considered. On the other hand, the European group prefers to concentrate on antennas of 12m diameter which, many believe, may be a more appropriate basis for a combined MMA/LSA instrument. In the face of this disparity it was agreed that the U.S. group would proceed with the design of the 10m and the European group would use their best efforts to design a 12m antenna. The goal would be to compare the two designs around the first of the year. The hope is that by that time not only will we know more about the performance of 10m/12m antennas but we will know more about the liklihood of a MMA-LSA merger. We will use this input to decide how best to proceed with the MMA antenna prototype.

The March MMA/LSA Technical Workshop is planned to the the first in a continuing series of such project interactions. The group will meet again toward the end of the year to keep in touch and evaluate progress toward the merger.