Advanced LIGO subsystems
are the organizational units of the overall project. Follow the links below to view the mission and progress of each subsystem.

Auxiliary Optics Core Optics
Data Acquisition Data and
Input Optics

Subsystem: Facilities Modifications and Preparations

The Facility Modification and Preparations (FMP) subsystem encompasses modifications to the permanent facility infrastructure and the site preparations required for the assembly and installation of new detector instruments. Buildings have been prepared for clean receiving, processing, assembly and storage. These modifications have required changes to HVAC, electrical, and plumbing systems. Pre-fabricated structures were added as needed. All large clean rooms are operational. Large air bake ovens, de-ionized water supplies, and aqueous and ultrasonic washers are in use for the cleaning and baking of all in-vacuum aLIGO parts. An inventory control system, with tracking for clean and bake load functions, is now being used in production, with additional capability in development for aggregation of parts and for tracking electronics versions. The inventory control system forms the hub of Advanced LIGO's parts management strategy, tracking the progress of hundreds of thousands of parts on their way to their final in-vacuum destinations.

All vacuum equipment functional requirements are the same as those in the initial LIGO design except that the vacuum level is required to be one order of magnitude lower (less than 10-7 torr; the present system operates at the Advanced LIGO level). Additional equipment (chambers, spool pieces, softwall clean rooms) is needed to accommodate additional arm cavity length for one interferometer and the desire for parallel assembly and installation in more chambers and staging areas. A larger diameter spool piece for the IO Mode Cleaner beam path is required. Several of the auxiliary optics chambers in the central building will be moved several meters along the beam line to accommodate the new optical system. The seismic isolation system requirements5 call for the Advanced LIGO subsystems to be compatible with the original LIGO vacuum envelope. Other elements of this subsystem are the installation fixtures and hardware, equipment and materials for in-vacuum component and vacuum equipment cleaning/baking, and the installation planning.

      Beam tube vibration sensing

    BSC support tube installation

  A septum viewport near HAM 1

      Beam tube insulation removal

    End station small gate valve

  Residual gas analyzer (RGA) setup

      HAM 1 viewport

    Turbopump controls

  Beam tube sans insulation

      ISI on test stand

    ISI on test stand

  Assembly area

      LVEA clean room

    Assembly clean rooms

  LHO staging building

Additional Facilities Photos

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