Engineering topics
Publications and source records attributed to Holmes, W..
We will describe the LTMPF, its objectives, its science requirements, and provide a brief description of the science investigations. The current status of the project and the facility design including results on the performance of flight-like subsystems will also be presented.
They present a formal thermodynamic treatment of the Josephson effect.
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We describe the design and development of the Low Temperature Microgravity Physics Facility, which is intended to provide long duration (4.5 months) low temperature (1.4K) and microgravity conditions for scientists to perform breakthrough investigations on board the International Space Station.
We describe the design and development of the Low Temperature Microgravity Physics Facility, which is intended to provide a unique environment of low temperature and microgravity for the scientists to perform breakthrough investigations on board the International Space Station.
Subsystems for a proof of concept cryogenic payload have been developed to demonstrate the ability to accommodate low temperature science investigations within the constraints of the Hitchhiker siderail carrier on the Space Shuttle.
Results from a search for anisotropy in the cosmic microwave background (CMB) are presented from the third flight of the Millimeter-wave Anisotropy experiment. The CMB observation occurred over 1.37 hours and covered a 6.24 sq deg area of the sky where very little foreground emission is expected. Significant correlated structure is observed at 6 and 9/cm. At 12/cm we place an upper limit on the structure. The relative amplitudes at 6, 9, and 12/cm are consistent with a CMB spectrum. The spectrum of the structure is inconsistent with thermal emission from known forms of interstellar dust. Synchrotron and free-free emission would both require unusually flat spectral indices at cm wavelengths in order to account for the amplitude of the observed structure. Although known systematic errors are not expected to contribute significantly to any of the three optical channels, excess sidelobe contamination cannot be definitively ruled out. If all the structure is attributed to CMB anisotropy, a value of the weighted rms of the 6 and 9/cm channels of Delta T/T(CMB) = 4.7 +/- 0.8 x 10 exp -5 (+/- 1 sigma) was measured. If the CMB anisotropy is assumed to have a Gaussian autocorrelation function with a coherence angle of 25 arcmin, then the most probable value is Delta T/T(CMB) = 4.2 +1.7 or -1.1 x 10 exp -5, where the +/- refers to the 95 percent confidence limits.
Results are presented from the third flight of the MAX experiment, an attitude-controlled balloon-borne millimeter-wave telescope with a 0.5 deg beam, a 1 deg chop, and a three-channel bolometric photometer. Several hours of high-quality data were obtained during a flight on 1991 June 5, including long integrations to search for CBR anisotropy, two separate measurements of dust in the Galactic plane, a brief scan of the Coma Cluster to search for the Sunyaev-Zel'dovich (SZ) effect, and a number of important systematic tests. Data from one of the long CBR integrations, carried out in a region of sky near the star Mu Pegasi, are presented. The primary structure in the data is shown to be emission from Galactic dust via its spectrum and correlation with the IRAS 100/micron map. Several approaches are used to fit this dust component and remove it from the data. An upper limit to CBR anisotropy of deltaT/T less than 2.5 x 10 exp -5 is obtained for a Gaussian autocorrelation function with coherence angle omega(c) = 25'. This limit is significantly higher than the measurement sensitivity of deltaT/T about 1 x 10 exp -5 due to the presence of residual structure in the data after removal of the dust component.
A system to remotely control job flow on a host computer from any touchtone telephone is briefly described. Using this system a computer programmer can submit jobs to a host computer from any touchtone telephone. In addition the system can be instructed by the user to call back when a job is finished. Because of this system every touchtone telephone becomes a conversant computer peripheral. This system known as the Remote Computer Control (RCC) system utilizes touchtone input, touchtone output, voice input, and voice output. The RCC system is microprocessor based and is currently using the INTEL 80/30microcomputer. Using the RCC system a user can submit, cancel, and check the status of jobs on a host computer. The RCC system peripherals consist of a CRT for operator control, a printer for logging all activity, mass storage for the storage of user parameters, and a PROM card for program storage.