ALMA (Atacama Large Millimeter/submillimeter Array) is the world's largest ground-based facility for observations in the millimeter/submillimeter regime. One of ALMA's outstanding characteristics is the large effort dedicated to the quality assurance (QA) of the calibrated and imaged data products offered to the astronomical community. The Data Management Group (DMG), in charge of the data processing, review, and delivery of the ALMA data, consists of approximately 60 experts in data reduction, from the ALMA Regional Centers (ARCs) and the Joint ALMA Observatory (JAO), distributed in fourteen countries. With a throughput of more than 3,000 datasets per year, meeting the goal of delivering the pipeline-able data products within 30 days after data acquisition is a huge challenge. This paper presents (a) the history of data processing at ALMA, (b) the challenges our team had and is still facing, (c) the methodology followed to mitigate the operational risks, (d) the ongoing optimization initiatives, (e) the current data processing status, (f) the strategy which is being followed so that, in a few Cycles from now, a team of approximately 10 data reducers (DRs) at JAO can process and review some 80% of the datasets collected during an observing cycle, and, finally, (g) the important role of the ARCs for processing the remaining datasets.
PEPPER is a high-speed differential Polarization-Encoded Photometer and Polarimeter developed in the Center
for Astronomical Adaptive Optics at the University of Arizona, Tucson, by Dr. Dan Potter and Matthew Graham.
PEPPER is capable of acting as a high-speed polarimeter by using electro-optical switching to chop between
standard star and target star, and between in and out-feature bandpass filter at frequencies fast enough to
suppress atmospheric variations. PEPPER is capable of either high-speed polarimetry or differential photometry
using a combination of simultaneous imaging and electro-optical switching. In the differential photometry mode,
PEPPER utilizes the electro-optical switching to calibrate instrumental and atmospheric photometric variation.
This technique coupled with a zero-read noise photon counting detector achieves photon noise limited results
demonstrated to an accuracy of less than 1 part in 105. Herein we present the design concept behind the
photometer and the polarimeter mode of PEPPER, as well as, results from observations in the differential
photometer mode at the Steward 90 inch telescope, at the Kitt Peak National Observatory, Tucson, Arizona.
Results from the analysis of near IR polarimetry observations of young stars with circumstellar disks taken at
the Gemini North Telescope with the Hokupa'a adaptive optics system are also presented.
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