Recent Extended Configuration Work

• Holdaway has been working on a mod to the current design, which was optimized for the most extended configuration. In this design, some of the inner configurations displayed inner sidelobes as large as 20 percent; mating to the most extended Conway configuration was non-optimal. In the modification, three configurations among the most extended are to be optimized.
  • Telecon of 18 March: Holdaway reported good progress on the most extended 'C' configuration and the intermediate 'B' configuration. Sidelobes are from two hour tracks off zenith. We aimed at NS 10% beam ellipticity so about 25 deg off zenith. -48 deg dec
    • 'B' configuration. Six new stations. 3-4 stations NW of APEX, one along there. Should be able to reuse one of the old ones, should be OK. 2 N of pipeline between Chascon and Chajnantor along road from Pampa la Bola. Probably OK. Three are south of pipeline roughly following it. These are quantitatively better than what we had before. B configuration has 9.5% max inner sidelobes, beam 27.8 mas x 25.6 mas. 8% noncircular, about 5% off target in resolution slightly higher. .
    • 'C' configuration. No new stations (other than those in 'B'. 5.8% sidelobes beam 19 x 16.7 mas aimed at 16.6 mas round.
• Next telecon Weds 26 March.