“B-Machine Polarimeter” is a telescope to measure the polarization of the cosmic microwave background (CMB).
B-Machine telescope was the project of Brian Dean Williams from University of California at Santa Barbara. This machine has been named for mapping the B-modes and is placed at a high altitude site of White Mountain Research Station (WMRS) at Barcroft, California. B-mode signals help in measuring the projected mass distribution over the entire observable Universe.
B-Machine telescope was first operated in the summer of 2008 at WMRS. Several have spent several years in development of this telescope. This telescope’s subsystems have been constructed and tested at University of California, Santa Barbara (UCSB) before installing it at WMRS.
This machine has been developed to test CMB (cosmic microwave background) polarization. “B-Machine uses a room temperature half wave plate technology to chop between polarization states and measure the polarization signature of the CMB.”
This technique is helpful in gathering information about the first fractions of the seconds, among the other things, of the universe, as for example this technique could help us in finding whether the theory of inflation was right as it is the only theory telling us about the very early universe.
This machine covers about 53% of the sky. Researchers are of the opinion that B-Machine could compete with Planck Satellite Mission in the future.
You can read thesis by going to the link mentioned in the reference.
Brian D. Williams (2013). B-Machine Polarimeter: A Telescope to Measure the Polarization of the
Cosmic Microwave Background arXiv arXiv: 1311.1879v1