Commissioning and Science Verification

ALMA is a very complicated instrument that contains a large number of separate subsystems e.g. antennas, receivers (front ends), back-end electronics and the correlator; getting these to work together as a single telescope is a major challenge. Two major tasks must be completed before ALMA is able to perform science observations:

• the individual subsystems must be delivered to Chile, constructed, integrated together and their performance confirmed as being according to specifications (Assembly, Integration and Verification or AIV)
• the various observing modes of the telescope must be tested and refined and the ability to attain the scientific goals of the instrument demonstrated (Commissioning and Science Verification or CSV)

In practice, as the numbers of telescopes in Chile continues to increase these two activities overlap significantly.

The Science Verification aspect of CSV will include observations suggested by the external community in response to an "Announcement of Opportunity" from the Project Scientist. The main goal of this phase is to demonstrate the capabilities of the instrument at an early stage, with all data and images being made public as soon as possible. There will subsequently be a Call for Proposals for Early Science.

A large number of people will be taking part in CSV, including staff at the Joint ALMA Office (JAO) and members of the ALMA Regional Centres. At the European ARC, we are committed to providing two person years of CSV support with the first CSV "liaison" departing for Chile in October 2009. Staff at the European ARC nodes can also take part in CSV providing they have the necessary expertise, subject to the approval of the ALMA Project Scientist. CSV visits must last for a minimum of three months and operate on the so-called Turno system: a typical month will consist of eight days working at the OSF, six days rest followed by two weeks working at the JAO in Santiago.