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 Computing Systems
Facilities Modifications	Input Optics
Interferometer Control	Pre-Stabilized Laser
Seismic Isolation	Suspensions

Subsystem: Core Optics

Advanced LIGO core optics for each interferometer include the input and end test masses (mirrors), compensation plates for the test masses, the main beam splitter, the power recycling mirror and the signal recycling mirror. The test masses weigh 40 kg; the beam splitter, recycling mirrors and compensation plates are similar to the test masses in diameter but thinner. Core optics are composed of ultra-high purity fused silica and are coated with layers of doped tantala. The test masses will scatter less than 10 ppm of incident light, a specification that requires a microroughness less than 0.16nm RMS.

      Livingston test mass (ITMY)

  Hanford beam splitter

      Large optic preparation

  Large optic testing

      aLIGO beam aplitter

  Applying First Contact

      Polished aLIGO end mirrors (ETM's)

  Inspection of an aLIGO optic

Additional Optics Photos

• Solder tests on a gold coating fixture
• A large optic storage cannister
• A test optic (folding mirror)

Explore Advanced LIGO    Construction Schedule
   Instrumentation and Astrophysics
   An Overview of the Upgrades
   The International Partnership
   Science Impacts
   LIGO Technology Transfers
   LIGO Scientific Collaboration
   Public Outreach
   LIGO Magazine
   aLIGO Home

• Last modified Oct 24, 2016
• For information about LIGO, contact info(at)ligo.caltech.edu
• LIGO is supported by the National Science Foundation. Any opinions, findings, conclusions or recommendations expressed here are those of the author(s) and do not necessarily reflect the views of the National Science Foundation