CAL will be a facility for the study of ultra-cold quantum gases in the microgravity environment of the International Space Station (ISS). It will enable research in a temperature regime and force free environment that is inaccessible to terrestrial laboratories. In the microgravity environment, up to 20 second long interaction times and as low as 1 picokelvin temperatures are achievable, unlocking the potential to observe new quantum phenomena. The CAL facility is designed for use by multiple scientific investigators and to be upgradable/maintainable on orbit. CAL will also be a pathfinder experiment for future quantum sensors based on laser cooled atoms. CAL is scheduled to launch in June 2017 on a Pressurized Cargo Vehicle in soft-stowage. After docking with ISS the CAL payload will be installed by astronauts into an EXPRESS (EXpedite the PRocessing of Experiments to Space Station) Rack inside the space station (upper picture). The EXPRESS Rack provides a standardized power, data, thermal, and mechanical interface to scientific payloads. CAL will occupy a quad locker space due to its size and power requirements. Following installation the payload will be operated remotely via sequence control from the Jet Propulsion Laboratory (lower picture). The initial mission will have a duration of 12 months with up to five years of extended operation.
A NASA Research Announcement was released on July 11, 2013 to solicit proposals from academic and research institutions to utilize the CAL facility.
Science Mission Objectives
The CAL science mission objectives are derived from the microgravity decadal survey. CAL utilizes the microgravity environment of the International Space Station (ISS) to form, create, and study ultra-cold quantum gases. CAL will be a technology and science pathfinder mission with the first ever demonstration of the following areas:
- Laser cooling of Rubidium (Rb) in a space environment
- Laser cooling of Potassium (K) in any microgravity environment
- Dual species laser cooling in a space environment
- Magnetic trapping in a space environment
- Evaporative cooling in a space environment
- Bose Einstein Condensate (BEC) in a space environment
- Degenerate Fermi gas in any microgravity environment
- Dual species degenerate gases, both Bose-Bose and Bose-Fermi in any microgravity environment
- Delta-kick Cooling to temperatures below 100 pK
- Interaction times greater than 5 seconds
- Atom interferometry in a space environment
As CAL is a multi-used facility, it will allow the scientific community to propose experiments using the instrument with the following over-arching capabilities:
- Study dual species degenerate gases, both Bose-Bose and Bose-Fermi in microgravity
- Study 87Rb, 3941K and 40K, and interactions between mixtures with residual kinetic energy below 100 pK with free expansion times greater than 5 seconds.
- Study the properties of quantum gases in the presence of external magnetic fields tuned near interspecies or single-species Feshbach resonances.
- Demonstrate atom interferometry with a Bragg beam
- Demonstration of Delta-Kick Cooling and Evaporative Cooling in a space environment.