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We report on the development of commercially fabricated multichroic antenna-coupled transition edge sensor (TES) bolometer arrays for cosmic microwave background (CMB) polarimetry experiments. CMB polarimetry experiments have deployed instruments in stages. Stage II experiments deployed with O(1000) detectors and reported successful detection of B-mode (divergence-free) polarization pattern in the CMB. Stage III experiments have recently started observing with O(10,000) detectors with wider frequency coverage. A concept for a stage IV experiment, CMB-S4, is emerging to make a definitive measurement of CMB polarization from the ground with O(400,000) detectors. The orders of magnitude increase in detector count for CMB-S4 require a new approach in detector fabrication to increase fabrication throughput and reduce the cost. We report on collaborative efforts with two commercial micro-fabrication foundries to fabricate antenna-coupled TES bolometer detectors. The detector design is based on the sinuous antenna-coupled dichroic detector from the POLARBEAR-2 experiment. The TES bolometers showed the expected I–V response, and the RF performance agrees with the simulation. We will discuss the motivation, design consideration, fabrication processes, test results, and how industrial detector fabrication could be a path to fabricate hundreds of detector wafers for future CMB polarimetry experiments.

The Simons Array is a next generation cosmic microwave background (CMB) polarization experiment whose science target is a precision measurement of the B-mode polarization pattern produced both by inflation and by gravitational lensing. As a continuation and extension of the successful POLARBEAR experimental program, the Simons Array will consist of three cryogenic receivers each featuring multichroic bolometer arrays mounted onto separate 3.5m telescopes. The first of these, also called POLARBEAR-2A, will be the first to deploy in late 2016 and has a large diameter focal plane consisting of dual-polarization dichroic pixels sensitive at 95 GHz and 150 GHz. The POLARBEAR-2A focal plane will utilize 7,588 antenna-coupled superconducting transition edge sensor (TES) bolometers read out with SQUID amplifiers using frequency domain multiplexing techniques. The next two receivers that will make up the Simons Array will be nearly identical in overall design but will feature extended frequency capability. The combination of high sensitivity, multichroic frequency coverage and large sky area available from our mid-latitude Chilean observatory will allow Simons Array to produce high quality polarization sky maps over a wide range of angular scales and to separate out the CMB B-modes from other astrophysical sources with high fidelity. After accounting for galactic foreground separation, the Simons Array will detect the primordial gravitational wave B-mode signal to r > 0.01 with a significance of > 5σ and will constrain the sum of neutrino masses to 40 meV (1σ) when cross-correlated with galaxy surveys. We present the current status of this funded experiment, its future, and discuss its projected science return.

Objective: To look for technical simplification and economic efficiency in the treatment of pediatric diabetic ketoacidosis (DKA) with subcutaneous use of the fast-acting insulin analog (lispro) and compare its use with regular intravenous insulin treatment.Research Design and Methods: In this controlled clinical trial from June 2001 to June 2003, we randomized 60 episodes of DKA with a blood glucose level > or = 16.6 mmol/l (300 mg/dl), venous pH <7.3 and/or bicarbonate <15 mmol/l, or ketonuria greater than + +. Of the 60 episodes, 30 were treated with subcutaneous lispro (0.15 units/kg) given every 2 h (lispro group) and the other 30 cases received continuous intravenous regular insulin (0.1 unit x kg(-1) x h(-1); CIRI group). Volume deficit was repaired with 10-ml/kg aliquots of 0.9% sodium chloride. Laboratory monitoring included hourly bedside capillary glucose, venous blood gas, beta-hydroxybutyrate, and electrolytes. Plasma blood glucose levels were measured on admission, 2 h after admission, when capillary blood glucose reached < or = 13.8 mmol/l (250 mg/dl), and 6, 12, and 24 h thereafter.Results: Capillary glucose levels decreased by 2.9 and 2.6 mmol x l(-1) x h(-1) in the lispro and CIRI groups, respectively, but blood glucose fluctuated at different time intervals. In the CIRI group, metabolic acidosis and ketosis resolved in the first 6-h period after capillary glucose reached 13.8 mmol/l, whereas in the lispro group, they resolved in the next 6-h interval; however, both groups met DKA recovery criteria without complications.Conclusions: DKA treatment with a subcutaneous fast-acting insulin analog represents a cost-effective and technically simplified procedure that precludes intensive care unit admission. [ABSTRACT FROM AUTHOR]

This article describes the use of the Fabry–Perot laser interferometer in the fringe mode to measure velocities of fast-moving reflecting surfaces, and includes a review of previously published work. We begin by describing the theory of the Doppler shift that applies to these situations, and include an experimental test of whether surface normal direction affects Doppler shift. Formulas are derived for the analysis of the effects of shocked, dispersive, moving transparent media on velocity measurements, including expressions for the velocity of light in a moving medium with moving boundaries. The Fabry–Perot method is compared with other techniques such as the VISAR interferometer. We then describe in detail a standard configuration developed at our facilities, discuss other configurations using optical fibers and more than one cylinder lens, and describe a new laser amplifier developed specifically for velocimetry. Methods of alignment, instrument calibration, surface preparation, and operation are included. Next, we present several methods of analysis, the choice of which depends on the absolute accuracy required, and examine many sources of possible error. These analytical techniques allow the motion of surfaces of reflectivity of at least 1% to be measured with an absolute precision of 0.5%. Time resolution can be a few nanoseconds, and is traded off for velocity resolution. One can make continuous velocity records of surfaces whose reflectivity under shock loading decreases to less than 1% of its initial value. We have simultaneously recorded three distinct velocity–time histories without ambiguity. [ABSTRACT FROM AUTHOR]