Publications by authors named "D M Harber"

We have developed a planar absolute radiometer for room temperature (PARRoT) that will replace the legacy C-series calorimeter as the free-space continuous-wave laser power detector standard at the National Institute of Standards and Technology (NIST). This instrument will lower the combined relative expanded measurement uncertainty (k = 2) from 0.84 % to 0.

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We present a new solar irradiance reference spectrum representative of solar minimum conditions between solar cycles 24 and 25. The Total and Spectral Solar Irradiance Sensor-1 (TSIS-1) Hybrid Solar Reference Spectrum (HSRS) is developed by applying a modified spectral ratio method to normalize very high spectral resolution solar line data to the absolute irradiance scale of the TSIS-1 Spectral Irradiance Monitor (SIM) and the CubeSat Compact SIM (CSIM). The high spectral resolution solar line data are the Air Force Geophysical Laboratory ultraviolet solar irradiance balloon observations, the ground-based Quality Assurance of Spectral Ultraviolet Measurements In Europe Fourier transform spectrometer solar irradiance observations, the Kitt Peak National Observatory solar transmittance atlas, and the semi-empirical Solar Pseudo-Transmittance Spectrum atlas.

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As part of the development of a spectrally uniform room-temperature absolute radiometer, we have studied the electrical noise of several bulk chip thermistors in order to estimate the noise floor and optical dynamic range. Understanding the fundamental limits of the temperature sensitivity leads inevitably to studying the noise background of the complex electro-thermal system. To this end, we employ a measurement technique based on alternating current synchronous demodulation.

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Background: Sustained hypotension, cardiogenic shock, and heart failure all imply a poor prognosis in acute myocardial infarction (MI). We assessed the benefit of adding 48 hours of intra-aortic balloon counterpulsation (IABP) to standard treatment for MI, in an international trial among hospitals without primary angioplasty capabilities.

Methods: We randomized 57 patients with MI complicated by sustained hypotension, possible cardiogenic shock, or possible heart failure to receive either fibrinolytic therapy and IABP or fibrinolysis alone.

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We investigate the relationship between the coherence of a partially Bose-condensed spinor gas and its temperature. We observe cooling of the normal component driven by decoherence as well as the effect of temperature on decoherence rates.

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