The Astrophysical Journal, Supplement Series
We describe two related experiments that measured the anisotropy in the cosmic microwave background (CMB). QMAP was a balloon-borne telescope that flew twice in 1996, collecting data on degree angular scales with an array of six high electron mobility transistor-based amplifiers (HEMTs). QMAP used an interlocking scan strategy to directly produce high signal-to-noise ratio CMB maps over a limited region of sky. The QMAP gondola was then refitted for ground-based work as the MAT/TOCO experiment. Observations were made from 5200 m on Cerro Toco in Northern Chile in 1997 and 1998 using time domain beam synthesis. MAT/TOCO measured the rise and fall of the CMB angular spectrum, thereby localizing the position of the first peak to lpeak = 216 ± 14. In addition to describing the instruments, we discuss the data selection methods, check for systematic errors, and compare the MAT/TOCO results to those from recent experiments. The previously reported data are updated to account for a small calibration shift and corrected to account for a small contribution from known sources of foreground emission. The resulting amplitude of the first peak for 160 < l < 240 is δTpeak = 80.9 ± 3.4 ± 5.1 μK, where the first uncertainty is statistical and the second is from calibration.
Miller, A.; Beach, J.; Bradley, S.; Caldwell, R.; Chapman, H.; Devlin, M. J.; Devlin, W. B.; Dorwart, W. B.; Herbig, T.; Jones, D.; Monnelly, G.; Netterfield, C. B.; Nolta, M.; Page, L. A.; Puchalla, J.; Robertson, T.; Torbet, E.; Tran, H. T.; and Vinje, W. E., "The QMAP and MAT/TOCO Experiments for Measuring Anisotropy in the Cosmic Microwave Background" (2002). Open Dartmouth: Faculty Open Access Articles. 3442.