NSF Award
2422892
The 2015 discovery and ongoing observations of gravitational waves by NSF's Laser Interferometer Gravitational-wave Observatory (LIGO) have transformed mankind's perception of the Universe, revolutionizing modern astrophysics, cosmology, and general relativity. Upgrades to the 4-kilometer LIGO detectors continue to expand their horizons, but LIGO can ultimately only access the local gravitational neighborhood. To achieve a cosmological reach, complement traditional modes of observation, and gravitationally probe the Universe back to its infancy will require larger-scale “next-generation” interferometers. The planned Cosmic Explorer (CE) Observatory, ten times larger than LIGO, will maintain and advance US leadership in this revolutionary new field. However, constructing the 40-km ultrahigh-vacuum (UHV) laser beamtubes needed to realize CE represents a key technical challenge. This award will support the development and testing of scalable technology to implement high-performance, reliable, and economical vacuum beamtubes at the largest physical scale ever attempted, on a timescale compatible with CE construction and observations. By helping to enable CE, the Cosmic Explorer Beamtube Experiment (CEBEX) advances gravitational wave observational science, while projecting novel studies of ultrahigh vacuum environments for physical science research, manufacturing technology, and surface science into new realms.<br/><br/>Under this award, the CEBEX team, based at LIGO Hanford Observatory, will design, construct, and test a 1.2m diameter by 120m long prototype UHV beamtube section as a technology pathfinder for the CE observatory. The scale of this activity requires the construction of a purpose-built lab structure on available land at the current LIGO site. Beamtube materials, construction methods, and industrial processes will be implemented and tested to confirm feasibility, scalability, and compliance with CE requirements. In the final year of the planned 4.25-year Award, the team will apply the results of this research to deliver to NSF an efficient conceptual reference design, parametric cost estimate, and schedule framework for CE beamtube construction. These will form key underpinnings of pending future CE design and construction initiatives.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
