- 1 ALMA has grown to 22 telescopes including three 7m telescopes in the Atacama Compact Array (ACA; right). On Oct 16, 2011 the array at the 16500 16,500 ft elevation Array Operations Site (AOS) was preparing for observations of a second set of highly ranked proposals. Credit: Carlos Padilla (NRAO/AUI/NSF):
September closed with the beginning of Early Science on ALMA. The 500 hours allotted to the 112 highest ranked (of 919 submitted) proposals for Cycle 0 of Early Science occur in several-day batches spread throughout the semester; the first four-day block had about 40 hours allocated to Science Operations and progress was made on several proposals. A second, five-day block was scheduled mid-October and produced further observations. These first observations targeted projects seeking the more compact of the two Cycle 0 arrays (see photo) for sources with appropriate sky positions.
Of the 112 highest priority projects whose observations have begun on ALMA, 38 were from the North American partners--the United States (35), Canada (3) and Taiwan. These were ranked most highly of the 280 proposals originating from the North American partners. Hence, the North American oversubscription rate for Cycle 0 Early Science was 7.4:1. A total of 236 N. A. scientists are collaborators on the 112 proposals given the Highest Priority for scheduling. These include 221 investigators at 55 different U.S. institutions. In North America, 935 astronomers registered at the ALMA portal. Worldwide, there were 2836 astronomers registered with ALMA and of those registered, nearly 90% were listed on one of the 919 submitted proposals.
During October four new sets of parts for AEM antennas arrived from Europe. The final three 7m antenna parts also arrived from Osaka via Kobe, completing delivery to the site of the entire Japanese complement of sixteen antennas. The 22nd of the North American antennas was shipped and is expected to arrive early in November. At the close of October, 51 of the ALMA antennas were on site. Twelve were under assembly at the Contractor areas, 7 in testing at the Operations Support Facility (OSF) and 22 at the AOS. Two of those at the OSF are due to arrive at the AOS by the beginning of November. Thus, more than one third of the final complement of 66 antennas to be delivered during construction are in use at the AOS.
A milestone for operation was achieved on 23 October when three 7m antennas achieved closure phase on their ACA foundations using the ACA correlator. One 12m antenna also stands on the ACA foundations, seen at far right in the photo above.
- Final Delivery of Mitsubishi antennas to the OSF Credit: Alison Peck (ESO/NAOJ/NRAO)
- ALMA has grown to 22 telescopes including three 7m telescopes in the Atacama Compact Array (ACA). On Oct 16, 2011 the array at the 16500 16,500 ft elevation Array Operations Site (AOS) was preparing for observations of a second set of highly ranked proposals. Credit: Carlos Padilla (NRAO/AUI/NSF):