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Evolution of Microwave Spectroscopy at the National Bureau of Standards (NBS) and the National Institute of Standards and Technology (NIST)
No full textThis paper describes the beginning and evolution of microwave rotational spectroscopic research starting in 1954 at the National Bureau of Standards (NBS), located at that time in Washington, DC, through the present at NIST in Gaithersburg, MD. David Lide was hired in 1954 to start this research employing Stark modulated waveguide septum cells. When Donald R. Johnson joined the lab in 1968, he developed parallel plate cells coupled with rf and DC discharge methods to study free radicals and transient species. In the mid 1980s Lovas and Suenram constructed a pulsed molecular beam Fourier Transform microwave (FTMW) spectrometer to study hydrogen bonded and van der Waals dimers and trimers. This article describes the types of molecules studied and the type molecular properties derived from these measurements as well as some of the instruments developed for these studies. The two major areas of application described are atmospheric chemistry and molecular radio astronomy
Instrument Control (iC) � An Open-Source Software to Automate Test Equipment
No full textIt has become common practice to automate data acquisition from programmable instrumentation, and a range of different software solutions fulfill this task. Many routine measurements require sequential processing of certain tasks, for instance to adjust the temperature of a sample stage, take a measurement, and repeat that cycle for other temperatures. We introduce an open-source Java program that processes a series of text-based commands that define the measurement sequence. These commands are in an intuitive format which provides great flexibility and allows quick and easy adaptation to various measurement needs. For each of these commands, the iC-framework calls a corresponding Java method that addresses the specified instrument to perform the desired task. The functionality of iC can be extended with minimal programming effort in Java or Python, and new measurement equipment can be addressed by defining new commands in a text file without any programming
Lunar Spectral Irradiance and Radiance (LUSI): New Instrumentation to Characterize the Moon as a Space-Based Radiometric Standard
No full textThe need to understand and monitor climate change has led to proposed radiometric accuracy requirements for space-based remote sensing instruments that are very stringent and currently outside the capabilities of many Earth orbiting instruments. A major problem is quantifying changes in sensor performance that occur from launch and during the mission. To address this problem on-orbit calibrators and monitors have been developed, but they too can suffer changes from launch and the harsh space environment. One solution is to use the Moon as a calibration reference source. Already the Moon has been used to remove post-launch drift and to cross-calibrate different instruments, but further work is needed to develop a new model with low absolute uncertainties capable of climate-quality absolute calibration of Earth observing instruments on orbit. To this end, we are proposing an Earth-based instrument suite to measure the absolute lunar spectral irradiance to an uncertainty1 of 0.5 % (k=1) over the spectral range from 320 nm to 2500 nm with a spectral resolution of approximately 0.3 %. Absolute measurements of lunar radiance will also be acquired to facilitate calibration of high spatial resolution sensors. The instruments will be deployed at high elevation astronomical observatories and flown on high-altitude balloons in order to mitigate the effects of the Earth�s atmosphere on the lunar observations. Periodic calibrations using instrumentation and techniques available from NIST will ensure traceability to the International System of Units (SI) and low absolute radiometric uncertainties
Robert Celotta 2012
No full textRobert Celotta was a physicist at the National Institute of Standards and Technology (NIST) from 1971-2017. He was the founding director of the NIST Center for Nanoscale Science and Technology. Source: Robert Celotta biographical file, NIST Archives
Oral history interview of Randall S. Caswell, Wednesday, November 14, 2012, / with J. William Gadzuk, Stephen N. Seltzer, David M. Gilliam, Allan D. Carlson, John J. Rush, David Lide.
No full textDr. Caswell came to the National Bureau of Standards (NBS) in 1952 and retired from the National Institute of Standards and Technology (NIST) in 1994. Dr. Caswell discusses his career and accomplishments as a Physicist at NBS/NIST. He served as NIST host and founding member of the Council on Ionizing Radiation Measurements and Standards
Oral history interview of Randall S. Caswell, Wednesday, November 14, 2012, / with J. William Gadzuk, Stephen N. Seltzer, David M. Gilliam, Allan D. Carlson, John J. Rush, David Lide.
No full textDr. Caswell came to the National Bureau of Standards (NBS) in 1952 and retired from the National Institute of Standards and Technology (NIST) in 1994. Dr. Caswell discusses his career and accomplishments as a Physicist at NBS/NIST. He served as NIST host and founding member of the Council on Ionizing Radiation Measurements and Standards
Paul Thomas Olsen
No full textPAUL THOMAS OLSEN
Inducted: 2012
Citation:
For significantly advancing science and metrology through high accuracy determinations of fundamental constants, helping to establish the use of electrical constants as standards and their application in redefining the SI
Tenure: 1963-1994
Birth: 1936, Brooklyn, New York
Death: 2009
Education:
Northrop Institute of Technology, Diploma (Aeronautical Engineering), 1957
Gettysburg College, Gettysburg, PA, BA (Physics), 1963
Positions held:
Research Physicist, Electricity Division, Center for Electronics and Electrical Engineering 1963-1988
Research Physicist, Fundamental Electrical Measurements Group, Electronics and Electrical Engineering Laboratory, 1988-1994
Honors:
U.S. Department of Commerce Silver Medal (1978), Gold Medal (1989)
Guest Scientist, National Physical Laboratory, Teddington, England (1971) working on the NPL gyromagnetic ratio of the proton in water measurement
Guest Scientist, National Physical Laboratory, Teddington, England (1985) working on the NPL watt balance
Memberships:
American Physical Society
Institute of Electrical and Electronics Engineers
Publications:
More than 40 publications and a patent including:
Olsen, P.T. and Driscoll, R.L., “Determination of gp’ at the National Bureau of Standards,” Atomic Masses and Fundamental Constants 4, Edited by Sanders, J.H. and Wapstra, A.H., Plenum Publishing Corp., London and New York, 471-474 (1972)
Olsen, P.T. and Williams, E.R., “Determination of the Gyromagnetic Ratio of the Proton gp’’” Atomic Masses and Fundamental Constants 5, Edited by Sanders, J.H. and Wapstra, A.H., Plenum Publishing Corp., London and New York, 538-544 (1976)
Williams, E.R. and Olsen, P.T. “New Measurement of the Proton Gyromagnetic Ratio and a Derived Value of the Fine-Structure Constant”, Phys. Rev. Lett. vol. 42 (1979)
Olsen, P.T., Cage, M.E., Phillips, W.D., and Williams, E.R., “The Realization of the Ampere at NBS,” IEEE Trans. Instrum. Meas., vol. IM-29, pp. 234-237 (Dec. 1980)
Olsen, P.T., Elmquist, R.E., Phillips, W.D., Williams, E.R., Jones, G.R. Jr., and Bower, V.E., “A Measurement of the NBS Electrical Watt in SI Units,” IEEE Trans. Instrum. Meas., vol. IM-38, pp. 238-244 (April 1989)
Williams, E.R., Steiner, R.L., Newell, D.B., and Olsen, P.T., “Accurate Measurement of the Planck Constant,” Phys. Rev. Lett., pp. 2404-2407, vol. 81 (1998
Reduction Formulae for Products of Theta Functions
No full textIn four cases it is already known that the product of two distinct Jacobian theta functions having the same variable z and the same nome q is a multiple of a single Jacobian theta function, with the multiple independent of z. The main purpose of the present note is to show that this property also applies in the remaining two cases
Variances of Cylinder Parameters Fitted to Range Data
No full textIndustrial pipelines are frequently scanned with 3D imaging systems (e.g., LADAR) and cylinders are fitted to the collected data. Then, the fitted as-built model is compared with the as-designed model. Meaningful comparison between the two models requires estimates of uncertainties of fitted model parameters. In this paper, the formulas for variances of cylinder parameters fitted with Nonlinear Least Squares to a points cloud acquired from one scanning position are derived. Two different error functions used in minimization are discussed: the orthogonal and the directional function. Derived formulas explain how uncertainties are propagated from measured ranges to fitted cylinder parameters
(Audio) Oral history interview of Russell Young, Wednesday, June 13, 2012 / with David Lide, Bill Gadzuk, Joseph Stroscio, John Villarrubia, Fred Scire, Cedric Powell, Ted Vorburger
No full textOral history interview of Dr. Russell Young at the National Institute of Standards and Technology in Gaithersburg, Maryland on Wednesday, June 13, 2012. Dr. Young was part of the Electron Physics Group at the NBS Atomic Physics Division in the mid-'60s where he started work in the field of mission microscope, which led to the invention of the topographiner, an instrument which led to the development of the scanning tunneling microscope. He retired in 1981