ABSTRACT
The Primordial Inflation Polarization Explorer (PIPER) is a balloon-borne telescope mission to search for inflationary gravitational waves from the early universe. PIPER employs two 32 × 40 arrays of superconducting transition-edge sensors, which operate at 100 mK. An open bucket Dewar of liquid helium maintains the receiver and telescope optics at 1.7 K. We describe the thermal design of the receiver and sub-Kelvin cooling with a continuous adiabatic demagnetization refrigerator (CADR). The CADR operates between 70 and 130 mK and provides ≈10 µW cooling power at 100 mK, nearly five times the loading of the two detector assemblies. We describe electronics and software to robustly control the CADR, overall CADR performance in flightlike integrated receiver testing, and practical considerations for implementation in the balloon float environment.
Subject(s)
Anti-Bacterial Agents/chemical synthesis , beta-Lactams/chemical synthesis , Azides , Carbonates , Cyclization , Imines , MethodsSubject(s)
Morbidity , Mortality , Vital Statistics , Adolescent , Adult , Age Factors , Aged , Female , Health , Hospitalization , Humans , Life Expectancy , Male , Methods , Middle Aged , Racial Groups , Sex Factors , United StatesABSTRACT
Health programs and activities today include a great variety of public and private efforts directed toward both fatal and nonfatal conditions. Most accepted summary measures of a population's health status, on the other hand, are based on death rates alone. They tell little about the health of the living and therefore provide an in-adequate basis for assessing the need for and success of many health measures. Consequently there has been considerable interest in recent decades in the development of summary indexes of health that reflect information on the living population as well as on the level of mortality. A previous report in this series examined the problem of determining what va ~iables might be used in constructing such measures. The re-port emphasized the need to devise indexes suited to specific objectives of measurement, and it focused on the limited goal of developing a more comprehensive index of changing health status for the United States as a whole. For that purpose a single index based on both mortality and morbidity rates was identified as a potentially useful device.
