2001/08/02 by A. Miller, J. Beach, S. Bradley +15 · 1 citation
Physics and Astronomy · #astro-ph
paper · pdf · doi:10.1086/339686
published as Astrophys.J.Suppl. 140 (2002) 115-142 · 31 pages, 11 figures, Submitted to ApJ
arxiv created 2001/08/02 · arxiv updated 2009/12/01
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 was the first experiment to use an interlocking scan strategy to directly produce high signal-to-noise CMB maps. The QMAP gondola was then refit 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 was the first experiment to see both 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, checks for systematic errors, and we compare the MAT/TOCO results to those from recent experiments. We also correct the data to account for an updated calibration and a small contribution from foreground emission. We find the amplitude of the first peak for l between 160 and 240 to be Tpeak=80.9 +/- 3.4 +/- 5.1 uK, where the first error is statistical and the second is from calibration.