Web Note: 12th February 2013
The RAL Space ALMA project team last week waved goodbye to the last ALMA front end to be assembled and tested in the European Front End Integration Centre (EuFEIC).
The Atacama Large Millimetre/sub millimetre Array (ALMA) telescope is located in a high and dry desert region of the Chilean Andes. The instrument is almost fully constructed with the last remaining pieces of the ‘technical jigsaw’ being delivered to Chile prior to its inauguration in March.
Crucial to the successful operation of the telescope are highly sensitive terahertz receivers, which are located on each of the 66 individual antennas that form ALMA, and detect the small signals emanating from distant astronomical sources. The Science and Technology Facilities Council (STFC), through RAL Space Department, has had the responsibility of assembling and testing 26 of the highly complex receiver systems and delivering them to Chile for installation and use on the various telescopes.
Front End Receiver testing in the EuFEIC
The receiver integration process has taken place in the European Front-End Integration Centre (EuFEIC), which was established at the Rutherford Appleton Laboratory, and within the RAL Space Department, in 2007. STFC-RAL was selected by the European Southern Observatory as the EuFEIC host and performed its integration procedures in parallel with two other FEICs located in North America and East Asia.
The integration and test process has been a demanding and difficult task, requiring assembly, measurement and evaluation of complex state-of-the-art receiver technology supplied from both internal and external sources. This feat of engineering had never before been undertaken on such a large scale for instrumentation operating in the millimetre wavelength range. To achieve it, bespoke integration and test facilities were developed in RAL Space, and which required the skills and expertise of the Millimetre-wave Technology Group staff at RAL. Calibration test rigs for the receivers were assembled in part of the clean room facilities in RAL Space to enable engineers to test each receiver before it was installed in the main telescope array. Key subassemblies were supplied by Technology Department Cryostat Group (ALMA Cryostats) and the RAL Space Millimetre-wave Technology Group (Photomixers).
The ALMA project is an international undertaking which is co-ordinated within Europe by ESO, and involves partners from North America and East Asia. STFC acts as a central link and hub for ALMA within the UK. A range of institutes have been involved, via STFC, at various stages of the array construction and include RAL, which also hosts the ALMA UK Project Office; UK Astronomy Technology Centre, Edinburgh; Cavendish Laboratory, University of Cambridge; University of Manchester and Jodrell Bank Observatory, and the University of Kent. All have played key roles in the design and construction of ALMA.
For more information please contact:
RAL Space Enquiries
