The discovery of the cosmic microwave background anisotropy is without question one of the most inspiring and fascinating discoveries in the history of physics. For the duration of human civilization, the CMB was always there, waiting to be discovered; but only in the last forty years have we finally learned to make use of this vast resource, to extract the information each photon has carried to us on a 13-billion-year journey from the early universe and to comprehend the profound implications. Over the past decade, the exponential increase in our understanding of the CMB has revolutionized our understanding of cosmology, creating new opportunities for exciting research never before envisioned.

With the success of the COBE and WMAP satellite missions, as well as many ground-based CMB observing campaigns such as ACBAR, DASI, and CBI, the angular power spectrum of CMB temperature anisotropies has been thoroughly characterized on a wide range of scales and shown to be remarkably consistent with the predictions of inflationary cosmology. The enormity of this accomplishment is evident not only in the beautiful agreement between these experiments—and additionally between complementary experiments in other fields, such as supernova IA measurements— but also in the fact that the model to which the results have converged lies in a completely unexpected region of the parameter space. This surprising turn of events can be better understood through measurements of the CMB polarization anisotropy. The E-mode polarization signal provides a valuable confirmation of the standard model and also breaks several important parameter degeneracies. Yet more tantalizing results remain hidden in the B-mode polarization signal, which carries the imprints of both gravitational radiation from the time of inflation and also gravitationally lensed E-mode signals.

This work describes in detail the CAPMAP experiment, an array of 16 correlation polarimeters that characterized the CMB polarization anisotropy in the range 200 [special characters omitted] ℓ [special characters omitted] 2500. We describe the instrument and its calibration briefly and then give a full account of the analysis pipeline. We then present our new results, which include one of the most sensitive detections of E-mode polarization to date and new upper limits on the B-mode anisotropy.