Vacuum Chamber for LIGO Lab at CalTech


Anderson Dahlen recently partnered with LIGO Lab at CalTech to complete

Back in the early 90s, CalTech built two massive beamlines for their LIGO lab in Washington and Louisiana. Anderson Dahlen’s task was to repurpose a section of leftover beamline from those projects and turn it into a vacuum chamber to run high vacuum experiments and observe what background gases came from the tube itself.

There was an advantage to repurposing the old beamline into a high-pressure vacuum system because the original equipment was manufactured at exactly the same time out of the same batch of material. This allowed LIGO a critical baseline from which to test off-gassing results in their experiments and have more accurate data.

Modifying the old length of the beamline presented the opportunity to utilize our inspection equipment to measure and understand the precise geometry – how it was curved, how round it was, and how much it was tapered. The LIGO vacuum chamber is a particular example of the harmony that can exist between science and craftsmanship. We know the science of how a weld occurs. We know the composition of a quality weld joint and how to test for precision and durability, but there is nothing to replace the level of skill needed to create the welds that went into the LIGO equipment. It takes a person with impeccable hand-eye coordination and steady skill to maintain the weld at its smallest size with uniform penetration along a very long distance.