EBEX is a balloon-borne polarimeter designed to measure the B-mode polarization
of the cosmic microwave background radiation. The instrument includes a 1.5 meter
Gregorian-type telescope and a cryogenic receiver housing 1432 bolometric transition
edge sensor detectors operating at 0.3◦ K. In this thesis I describe my work on the development
and characterization of the EBEX cryogenic system and of several electronics
I developed CANbus-based software to monitor temperatures inside the receiver
and to control the operation of two sub-Kelvin adsorption refrigerators. I commissioned
and tested an experiment-wide timing system that tags data from all subsystems with
an accuracy that is a factor of 10 better than required. I constructed and tested two
pressure vessels that store data on board.
Data collected during the EBEX test flight in June 2009 show that all these subsystems
performed according to predictions. The temperatures of the cryostat were stable.
An analysis of the temperature data finds no scan synchronous signal in the cryostat
temperatures. The timing system and pressure vessels operated as expected.
A calibrator was installed inside the receiver to monitor detector responsivity variations.
I analyzed the data from the test flight and show that in its current configuration
the calibrator is inadequate.