Seven Vertex antennas and four Mitsubishi Electric Company (Melco) antennas are now on the ALMA site in northern Chile. Six of these 11 antennas are visible in the panorama above (left center). Five antennas are in various stages of construction in the Vertex Site Erection Facility (SEF, left center); two Vertex antennas are being tested just outside the building. The four Melco antennas can be seen in front of the Vertex complex. The large flat area in the left foreground is being prepared for the first AEM antennas that will soon arrive from Europe.
The Operation Support Facility (OSF) Technical Building complex (right) is being readied for the arrival of the first production antennas. An ALMA transporter will move antennas to the OSF Technical Building courtyard (center right). It is expected that Melco antenna No 2 will be the first antenna moved to the OSF Technical Building complex. The two ALMA transporters can be seen in their shelter (above center right).
At the Array Operations Site (AOS) at 5000m, concrete has been poured for 27 antenna foundations. In the (AOS) Technical Building, the first quadrant of the 64-station correlator and the Atacama Compact Array 16-station correlator have been installed.
The first ALMA Front End was inserted into the receiver cabin on Antenna No 2 from Mitsubishi Electric Company (Melco) on October 13. Although the antenna is not yet fully accepted by ALMA, it now contains a substantially complete set of production ALMA electronics. The Front End is dominated by the massive dewar (blue). At its base are the warm electronic assemblies that provide and convey signals to and from the receiver cartridges. The receiver cartridges are inserted in the dewar, where they are cooled to 4 K. Four preproduction cartridges have been installed in the first Front Ends, to cover the ALMA bands at 3mm (Band 3), 1.3mm (Band 6), 0.85mm (Band 7) and 0.45mm (Band 9). Receivers whose design was based on the ALMA preproduction cartridges have been successfully deployed at many millimeter observatories, including the Arizona Radio Observatory (ARO) and the Combined Array for Research in Millimeter-wave Astronomy (CARMA) in the U. S. The first Front End was assembled and tested at the North American Front End Integration Center at the NRAO Technology Center in Charlottesville.
As reported earlier, other elements in the interface between the Front End and the electronics associated with the correlator and reference signals were installed and tested already, such as the part of the Back End built at the Pete V. Domenici Science Operations Center in Socorro, NM. Elements of the Back End and of the Front End were, of course, fabricated in many labs participating in ALMA.
A number of tests and reviews are being conducted for the Melco antenna as part of the acceptance process. This process is expected to result in antenna acceptance by the end of the year. Similar tests and reviews are occurring concurrently on the Vertex antennas, which should be accepted early in 2009. Components of the AEM antennas are expected to arrive at the Operations Support Facility near year-end.
Technical staff involved in ALMA construction and operations generally live in Santiago and travel to the Operations Support Facility in northern Chile for about a week, followed by time off and work in Santiago, before repeating the cycle. One new arrival in Santiago is Stuartt Corder, who began work on the commissioning team on 1 October along with colleagues Antonio Hales, who had a postdoctoral position in Charlottesville, and Tsuyoshi Sawada, from NAOJ.
Corder moved from Cal Tech with his wife Jennifer and baby daughter, Vivian. Santiago AUI/NRAO staff, led by Eduardo Hardy, worked with Charlottesville-based staff to ensure a smooth transition. Happily, Stuartt reports that the move went well, and that he had found time to resubmit one paper, now in press, and begin work on another. The family has appreciated the abundance of playground-equipped parks, one with a small aviary. They will move into longer-term quarters in a few weeks, one with ‘a wonderful view of the Andes from our patio.’ The contrast in housing affordability with Los Angeles is considerable. Spanish lessons have begun, and the family has begun to discover various interest groups. Vivian decided to begin her own discovery phase, taking her first steps just recently.