NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.

Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.

U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Physics

Radiation

Search Publications

Search Title, Abstract, Conference, Citation, Keyword or Author
  • Published Date
Displaying 151 - 175 of 259

Absolute pulse energy measurements of soft x-rays at the Linac Coherent Light Source

August 25, 2014
Author(s)
Uwe Arp, Alexander Sorokin, Ulf Jastrow, Pavle Jurani?, Svea Kreis, Mathias Richter, Yiping Feng, Dennis Nordlund, Kai Tiedtke, Philip Heimann, Bob Nagler, Hae Ja Lee, Stephanie Mack, Marco Cammarata, Oleg Krupin, Marc Messerschmidt, Michael Holmes , Michael Rowen, William Schlotter, Stefan Moeller, Joshua Turner
This paper reports novel measurements of x-ray optical radiation on an absolute scale from a recently developed source of radiation generated in the soft x-ray regime of a free electron laser. We give a brief description of the physics behind the

Post-Irradiation Study of the Alanine Dosimeter

July 14, 2014
Author(s)
Marc F. Desrosiers
Post-irradiation stability of high-dose dosimeters has traditionally been an important measurement influence quantity. Though the exceptional stability of the alanine dosimeter response with time has rendered this factor a non-issue for routine work, the

On the limits of spin-exchange optical pumping of 3He

July 2, 2014
Author(s)
Thomas R. Gentile, T G. Walker, E Babcock, Qiang NMN Ye, Wangchun Chen
Using diode bar lasers spectrally narrowed with chirped volume holographic gratings (VHGs), we have obtained an improvement in the 3He polarization achievable by spin-exchange optical pumping (SEOP). As compared to our past results with lasers narrowed

Effects of Dose Fractionation on the Response of Alanine Dosimetry

June 28, 2014
Author(s)
Marc F. Desrosiers, John Logar, Brad Lundahl
Alanine dosimetry is well established as a transfer standard and is becoming more prevalently used as a routine dosimetry system for radiation processing. Many routine measurement applications in radiation processing involve absorbed dose measurements

Neutron Interferometric Measurement of the Scattering Length Difference Between the Triplet and Singlet States of N-3 He.

June 4, 2014
Author(s)
Michael G. Huber, Muhammad D. Arif, Wei-Chen N. Chen, Thomas R. Gentile, Daniel S. Hussey, T C. Black, Dimitry A. Pushin, F. E. Wiefeldt, C.B Shahi, L Yang
We report a new determination of the n-Helium-3 scattering length difference Δ b = (−5.411 ± 0.031 (statistical) ± 0.039 (systematic) ) fm between the triplet and singlet states using a neutron interferometer. This revises our previous result Δ b = (−5.610

Noble Gas Excimer Scintillation Following Neutron Capture in Boron Thin Films

April 11, 2014
Author(s)
Alan K. Thompson, Jacob McComb, Charles W. Clark, Michael A. Coplan, Mohamad Al-Sheikhly, Robert E. Vest
Far-ultraviolet (FUV) scintillation signals have been measured in heavy noble gases (argon, krypton, xenon) following boron-neutron capture (10B(n,α)7Li) in 10B thin films. The observed scintillation yields are comparable to the yields from some liquid and

Improvements and Extensions of the Neutron Cross Section and Fluence Standards

April 4, 2014
Author(s)
Allan D. Carlson, V G. Pronyaev, R. Capote, F. J. Hambsch, F. Kappeler, C. Lederer, A Mengoni, R O. Nelson, A.J.M Plompen, P Schillebeeckx, S Simakov, S. Tagesen, H Vonach, A Vorobyev, A Wallner
Updated evaluations of the standards are needed within a few years for new versions of several cross section libraries, e.g.; ENDF/B and JEFF, that have been planned. To update the standards, a collaboration, supported by an IAEA Data Development Project

Polarized 3HE Spin Filters for Neutron Science

February 12, 2014
Author(s)
Thomas R. Gentile, Wei-Chen N. Chen
The large spin dependence of the absorption cross section for neutrons by 3He gas provides a method to polarize neutron beams. For certain applications, such polarized 3He-based neutron "spin filters" have advantages over conventional neutron optical

A New NIST Primary Standardization of 18F

February 1, 2014
Author(s)
Ryan P. Fitzgerald, Brian E. Zimmerman, Denis E. Bergeron, Jeffrey T. Cessna, Leticia S. Pibida, Denise S. Moreira
A new primary standardization of 18F by NIST is reported. The standard is based on live-timed beta- gamma anticoincidence counting with confirmatory measurements by three other methods: (i) liquid scintillation (LS) counting using CIEMAT/NIST 3H efficiency

Measurement Traceability in Medical Physics

January 1, 2014
Author(s)
Lisa R. Karam
Medical physics, the joining of physics with healthcare, requires a level of quality assurance beyond many applications of the physical sciences. Always the health, and often the life, of the patient depends on the precise and accurate implementation of

The Importance of Dosimetry Standardization in Radiobiology

December 30, 2013
Author(s)
Marc F. Desrosiers, Larry A. DeWerd, James Deye, Patricia Lindsay, Mark K. Murphy, Michael G. Mitch, Francesca Macchiarini, Strahinja Stojadinovic, Helen Stone
Radiation dose is central too much of radiobiological research. Precision and accuracy of dose measurements and reporting of the measurement details should be sufficient to allow the work to be interpreted and repeated and to allow valid comparisons to be

Standardization of 237Np

December 4, 2013
Author(s)
Lizbeth Laureano-Perez, Ryan P. Fitzgerald, Ronald Colle
The standardization of 237Np was investigated. The certified massic activity for 237Np was obtained by 4 liquid scintillation (LS) counting with correction for the 233Pa daughter using the CIEMAT/NIST efficiency tracing method using a 3H standard

Improved Determination of the Neutron Lifetime

December 2, 2013
Author(s)
Jeffrey S. Nico, A. T. Yue, Maynard S. Dewey, David M. Gilliam, G L. Greene, A. Laptev, William M. Snow, F. E. Wiefeldt
The most precise determination of the neutron lifetime using the beam method was completed in 2005 and reported a result of tau_n = (886.3 ± 1.2 [stat] ± 3.2 [sys]) s. The dominant uncertainties were attributed to the absolute determination of the fluence

Micelle size effect on Fe-55 Liquid Scintillation Efficiency

December 1, 2013
Author(s)
Denis E. Bergeron, Lizbeth Laureano-Perez
We used efficiency tracing techniques to study the micelle size effect on liquid scintillation counting of the low-energy Auger electron emitter, 55Fe. We determined micelle hydrodynamic diameters for specific LS cocktails via dynamic light scattering, and

ITRAP+10 Spectroscopic Radiation Portal Monitor Testing

November 14, 2013
Author(s)
Anne L. Sallaska, Leticia S. Pibida, Huaiyu H. Chen-Mayer, Luc Murphy, Christina Ward
The Illicit Trafficking Radiation Assessment Program (ITRAP+10) is an international effort of the Department of Homeland Security’s Domestic Nuclear Detection Office (DHS/DNDO), the European Commission’s Joint Research Center (EC-JRC), and the

High-resolution K-shell spectra from laser excited molybdenum plasma

November 1, 2013
Author(s)
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 radiation)
Was this page helpful?