You searched on: Author: Lawrence Hudson
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1. A simple method for high-precision calibration of an angle encoder using an electronic nulling autocollimator
Lawrence T Hudson, M N Kinnane, Albert Henins, M H Mendenhall
We describe a simple method for high-precision rotary angle encoder calibration. By using a redesigned electronic nulling autocollimator, a mirrored-polygon artifact is calibrated simultaneously with determining the encoder error function over a rota ...
2. New x-ray measurements shed light on discrepancy between experiment and QED
Lawrence T Hudson, C T Chantler, A.T. Payne, M N Kinnane, John D Gillaspy, L F Smale, Albert Henins, J A Kimpton, E Takacs
Quantum Electro-Dynamics (QED) is the best tested theory of our physical world, yet significant
disagreements have emerged between attempts to apply QED to exotic atomic systems. A recent
15 parts-per-million (ppm) experiment on muonic hydrogen, in ...
3. Ultra-Thin Curved Transmission Crystals for High Resolving Power (up to E/¿E=6300) X-Ray Spectroscopy in the 6 keV to 13 keV Energy Range
Lawrence T Hudson, John F Seely, Jack Leigh Glover, Albert Henins, Nino R. Pereira
Ultra-thin curved transmission crystals operating in the Cauchois spectrometer geometry were evaluated for the purpose of achieving high spectral resolution in the 6 keV to 13 keV x-ray energy range. The crystals were silicon (111) and sapphire R- cu ...
4. The Metrology of a Rastered Spot of X Rays used in Security Screening
Journal of Research (NIST JRES)
Lawrence T Hudson, Jack Leigh Glover, Ronaldo Minniti
In recent times, ionizing radiation has been used around the world to screen persons for non-
medical purposes, namely to detect bulk explosives or other contraband hidden on the body
including materials not registered by metal detectors. In contr ...
5. Measurement of High-Energy (10 keV to 60 keV) X-Ray Spectral Line Widths with eV Accuracy
John F Seely, Jack Leigh Glover, Lawrence T Hudson, Yuri Ralchenko, Nino R. Pereira, U. Feldman, C. Di Stefan
A high resolution crystal spectrometer (HRCS) utilizing a crystal in transmission geometry has been developed and experimentally optimized to measure the line widths of emission lines in the 10 keV to 60 keV energy range with eV accuracy. The spectro ...
6. Measurement of the O2O3O4 and O3O4O5 Super Coster-Kronig Rates in Tungsten via Asymmetric Diffraction Spectrometry
Lawrence T Hudson, John F Seely, Jack Leigh Glover, Yuri Ralchenko, Nino R Pereira, Uri Feldman
The tungsten Lγ transitions between 11 keV and 12 keV and Kα transitions from 57 keV to 60 keV were produced by a laboratory electron-bombarded x-ray source and simultaneously recorded with high-resolution by using multiple diffraction plan ...
7. High-resolution K-shell spectra from laser excited molybdenum plasma
Lawrence T Hudson, C.I Szabo, P Indelicatio, John F Seely, T Ma
X-ray spectra from Molybdenum plasmas were recorded by a Cauchois-type cylindrically bent Transmission Crystal Spectrometer (TCS). The absolutely calibrated spectrometer provides an unprecedented resolution of inner shell transitions (K x-ray radiati ...
8. A method for organic/inorganic differentiation using an x-ray forward/backscatter personnel scanner
Jack Leigh Glover, Lawrence T Hudson
A method is proposed for performing organic/inorganic materials discrimination using an x-ray forward/backscatter scanner. The method is demonstrated using a commercially available personnel security-screening system and requires only image post proc ...
9. Tungsten L Transition Line Shapes and Energy Shifts Resulting from Ionization in Warm Dense Matter
Lawrence T Hudson, John F Seely, Bruce V. Weber, D. G. Phipps, Nino R. Pereira, D Mosher, K. Slabkowska, M. Polasik, J Rzadkiewicz, S Hansen, Uri Feldman, Joseph W. Schumer
High resolution spectra of the W L transitions in the energy range 8 keV to 12 keV from warm dense plasmas generated by the Naval Research Laboratory‰s Gamble III pulsed power machine were recorded by a transmission-crystal x-ray spectrometer with ± ...
10. Reply to ,Comment on "Testing Three-body Quantum Electrodynamics with Trapped Ti20+ Ions: Evidence for a Z-Dependent Divergence between Experiment and Calculation"
Lawrence T Hudson, C T Chantler, M N Kinnane, John D Gillaspy, A.T. Payne, L F Smale, Albert Henins, Joshua M Pomeroy, J A Kimpton, E Takacs, K Makonyi
We find that Epp‰s  hypothesis - namely that the current experimental data set is well represented by a small constant or zero offset from the predictions of Artemyev et al.  - is not supported by standard statistical analysis. We find that add ...