Fred Young Submillimeter Telescope Nears Deployment with Cornell CLASSE Contributions
The Fred Young Submillimeter Telescope (FYST) is scheduled for first light in 2026. Its development and preparation for deployment in the Parque Astronómico Atacama, Chile, have involved personnel from the Cornell Laboratory for Accelerator-based Sciences and Education (CLASSE), including engineers, machinists, electronics specialists, riggers, and support staff.
Operational Parameters and Scientific Objectives
FYST will operate at an altitude of 18,400 feet (5,600 meters) above sea level. This high-altitude location minimizes atmospheric interference, facilitating several scientific investigations. These include mapping the evolution of the universe from the formation of early stars and galaxies, measuring the growth of galaxy clusters influenced by dark matter, investigating magnetic fields within the Milky Way, and detecting polarization signals in the cosmic microwave background potentially indicative of primordial gravitational waves.
According to Mike Niemack, professor of physics and astronomy at Cornell and lead scientist for FYST’s Prime-Cam instrument, the telescope's optical throughput is approximately ten times greater than previous submillimeter telescopes, enabling expanded research capabilities in cosmic microwave background studies and galaxy formation mapping.
Prime-Cam Instrument Development
Prime-Cam, one of two planned instruments for FYST, is being outfitted at Cornell’s Space Sciences building. It incorporates multiple low-temperature stages, silicon lenses, optical filters, detector arrays, and readout components. The instrument is designed to operate at cryogenic temperatures, with critical detector stages cooled to near absolute zero. It must maintain optical alignment during intercontinental transport and subsequent assembly in a high-altitude, oxygen-scarce environment, where work durations are regulated.
CLASSE’s involvement includes design adaptation, response to testing results, and coordination across technical disciplines.
Engineering and Fabrication
Mechanical Engineering Contributions
Dave Burke, a mechanical engineer at CLASSE, has supported the project through testing and preparation phases. During initial cool-down testing of Prime-Cam, an issue was identified involving excess heat load on the coldest stage, which affected temperature attainment. The cryostat's requirements included a low vacuum, optical alignment, and an instrument temperature below one Kelvin. The team focused on:
- Improving wire management.
- Sealing light leaks.
- Adding a radiation shield to the four-Kelvin plate of the dilution refrigerator.
These modifications, completed within one week, reduced the heat load from 330 microwatts to 30 microwatts and lowered the temperature from 130 millikelvin to 50 millikelvin (approximately -457 degrees Fahrenheit).
Engineering designs for FYST also consider the high-altitude working conditions. Components are designed for easier lifting, alignment, and assembly, complemented by custom tooling, to account for reduced atmospheric density and regulated work hours at the site.
Machine Shop Operations
The 'raft,' a one-ton steel structure supporting the Prime-Cam instrument, required precision fabrication. This structure supports a six-foot diameter aluminum cryogenic chamber with multiple interfaces that demand precise alignment. Terry Neiss, CLASSE machine shop supervisor, stated that the project necessitated coordination between CLASSE and LASSP machine shops due to the size and complexity of components. Components fabricated at room temperature are designed to perform reliably at cryogenic temperatures and withstand intercontinental transport.
Electronics Development
CLASSE’s electronics shop develops systems that operate at temperatures near absolute zero. John Barley of the CLASSE electronics group noted cross-project experience among the electronics staff, which contributes to projects like FYST, the CMS project, and Cornell’s accelerator complex. This specialized expertise is required for electronics designed to withstand repeated thermal cycling and function at extreme low temperatures.
Procurement of Specialized Components
Some Prime-Cam components are sourced from specialized international vendors, including those in Germany. CLASSE procurement facilitated the integration of new vendors and the acquisition of specific items, such as superconducting coaxial cabling. These cables are designed to become superconducting and operate at 0.1 Kelvin, requiring handling of international logistics.
Logistics and Deployment Preparation
Rigging and Transport
As Prime-Cam approaches deployment, the focus shifts to logistical planning. The instrument will be moved from the Space Sciences building to Wilson Synchrotron Laboratory. At Wilson Lab’s high-bay space, CLASSE’s rigging crew will use overhead cranes and specialized equipment for a final "dry fit." This process ensures the multi-ton instrument can be safely positioned on the raft, then lifted and prepared for packing into its shipping container for transport to Chile.
Ed Foster, lead rigger at CLASSE, explained that moving heavy equipment within Cornell’s historical buildings often requires using steel plates for bridging thresholds, machine skates for rotation, and hydraulic rams for movement through constrained spaces. The rigging crew also welded the raft that supports Prime-Cam.
Project Collaboration
FYST is a project of CCAT Observatory, Inc., a Cornell-led collaboration. This collaboration includes a German consortium (University of Cologne, University of Bonn, Max Planck Institute for Astrophysics in Garching) and a Canadian consortium led by the University of Waterloo. CLASSE’s technical staff contributes to the project through its collaborative approach and specialized expertise.