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Search Publications by: John T. Woodward IV (Fed)

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Displaying 1 - 25 of 123

Measurements of Absolute, SI-traceable Lunar Irradiance with the Airborne LUnar Spectral Irradiance (air-LUSI) Instrument

May 5, 2022
Author(s)
John T. Woodward IV, Kevin Turpie, Thomas Stone, S. Andrew Gadsden, Andrew Newton, Stephen Maxwell, Steven Grantham, Thomas Larason, Steven W. Brown
The Airborne LUnar Spectral Irradiance (Air-LUSI) instrument is designed to make low uncertainty, hyperspectral measurements of the lunar spectral irradiance from an ER-2 aircraft from altitudes above 95 % to 99 % of the atmosphere. Measurements cover the

A pyroelectric detector-based method for low uncertainty spectral irradiance and radiance responsivity calibrations in the infrared using tunable lasers

April 4, 2022
Author(s)
Brian Alberding, John Woodward, Ping-Shine Shaw, Leonard Hanssen, Catherine Cooksey, Joseph P. Rice
The standard uncertainty of detector-based radiance and irradiance responsivity calibrations in the short-wave infrared (SWIR) traditionally has been limited to around 1 % or higher by the low spatial uniformity of detectors used to transfer the scale from

The Irradiance Instrument Subsystem (IRIS) on the Airborne-Lunar Spectral Irradiance (Air-LUSI) Instrument

March 23, 2022
Author(s)
Steven Grantham, Thomas C. Larason, Clarence Zarobila, Stephen Maxwell, John Woodward, Kevin Turpie, S. Andrew Gadsden
The objective of the airborne LUnar Spectral Irradiance (air-LUSI) project is to make low uncertainty, SI-traceable measurements of the lunar spectral irradiance in the visible to near-infrared (VNIR) region from an aircraft above most of the optically

Molecular-scale Structural and Functional Characterization of Sparsely Tethered Bilayer Membranes

October 12, 2021
Author(s)
Duncan McGillivray, Gintaras Valincius, David J. Vanderah, W Febo-Ayala, John T. Woodward IV, F Hienrich, John J. Kasianowicz, M Losche
Surface-tethered biomimetic bilayer membranes (tethered lipid bilayer membranes, tBLMs) have been formed on gold surfaces from phospholipids and a synthetic 1-thiahexa(ethy lene oxide) lipid, WC14. They have been characterized using electrochemical

Characterization and Absolute Calibration of an AERONET-OC Radiometer

April 15, 2021
Author(s)
B. Carol Johnson, Giuseppe Zibordi, Steven W. Brown, Michael Feinholz, Mikhail Sorokin, Ilya Slutsker, John T. Woodward IV, Howard Yoon
The Ocean Color component of the global Aerosol Robotic Network (AERONET-OC) utilizes CE-318 sun photometers modified for above-water radiometry from fixed structures such as oil rigs, lighthouses, and service platforms. Primarily, AERONET-OC measurements

Optical and Mechanical Design of a Telescope for Lunar Spectral Irradiance Measurements from a High-Altitude Aircraft

September 8, 2020
Author(s)
Clarence Zarobila, Steven Grantham, Steven W. Brown, John T. Woodward IV, Stephen Maxwell, Dana R. Defibaugh, Thomas Larason, Kevin Turpie
We have designed a non-imaging telescope for measurement of the spectral irradiance of the moon. The telescope was integrated into a wing pod of a NASA ER-2 research aircraft to measure lunar spectral irradiance during flight. The telescope and support

Invited Article: Advances in Tunable Laser-based Radiometric Calibration Applications at the National Institute of Standards and Technology, USA

September 26, 2018
Author(s)
John T. Woodward IV, Ping-Shine Shaw, Howard Yoon, Yuqin Zong, Steven W. Brown, Keith R. Lykke
Recent developments at the National Institute of Standards and Technology's facility for Spectral Irradiance and Radiance responsivity Calibrations using Uniform Sources (SIRCUS) are presented. The facility is predicated on the use of broadly tunable

CALIBRATION AND CHARACTERIZATION OF A SEAPRISM RADIOMETER FOR AERONET-OC

June 19, 2015
Author(s)
Bettye C. Johnson, Steven W. Brown, John T. Woodward IV, Keith R. Lykke, Giuseppe Zibordi
The global Aerosol Robotic Network for Ocean Color (AERONET-OC) program utilizes AERONET CE-318 sun photometers (termed “SeaPRISMs”) modified for in-air observations of ocean waters situated on oil drilling rigs, off-shore lighthouses, or other platforms

SI-Traceable Calibrations of Celestial Objects

May 14, 2015
Author(s)
Keith R. Lykke, Claire E. Cramer, John T. Woodward IV
Photometric calibration is currently the leading source of systematic uncertainty in supernova surveys that aim to determine the nature of dark energy. The bulk of this uncertainty is due to imperfect knowledge of the spectral energy distribution of stars