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 76 - 100 of 259

Carbon Nanotube Thin Film Patch Antennas for Wireless Communications

May 24, 2019
Author(s)
E. A. Bengio, Damir Senic, Lauren W. Taylor, Robert J. Headrick, Michael King, Peiyu Chen, Charles A. Little, John M. Ladbury, Chris Long, Christopher L. Holloway, Aydin Babakhani, James Booth, Nate Orloff
Early work on carbon nanotube (CNT) antennas indicated that their performance could not match that of metals such as copper. However, recent improvements in fluid phase CNT processing have yielded macroscopic CNT materials with better alignment and

Scatter corrections in x-ray computed tomography: a physics-based analysis

May 22, 2019
Author(s)
Zachary H. Levine, Timothy Blattner, Adele Peskin, Adam L. Pintar
Fundamental limits for the calculation of scattering corrections within X-ray computed tomography (CT) are found within the independent atom approximation from an analysis of the cross sections, CT geometry, and the Nyquist sampling theorem, suggesting

Spectrometer stray light can bias retrievals of solar-induced fluorescence

May 14, 2019
Author(s)
Loren Albert, Katherine Cushman, Yuqin Zong, David Allen, Luis Alonso, James Kellner
Remote sensing of solar induced chlorophyll fluorescence (SIF) promises a significant advance in our ability to quantify gross primary productivity across spatial scales. Because the fluorescence emission is usually 5 % of recorded canopy radiance

A Synchrotron X-ray Micro-Spectroscopy Study of the Explosive Melt Glass Derived From the Trinity Nuclear Test

April 28, 2019
Author(s)
Bruce Ravel, Daniel E. Crean, Daniel J. Bailey, M. C. Stennett, Claire L. Corkhill, Ryan Tappero, N. C. Hyatt
Trinitite, the explosive melt glass derived from the Trinity nuclear test, is of interest as a model material for nuclear forensics investigation. However, there remains uncertainty as to the mechanism of trinitite formation. In this study, new insight is

Multi-Energy X-Ray Tomography of an Optical Fiber: The Role of Spatial Averaging

March 14, 2019
Author(s)
Zachary H. Levine, Adele P. Peskin, Edward J. Garboczi, Andrew Holmgren
Using a commercial X-ray tomography instrument, we have obtained reconstructions of a graded-index optical fiber with voxels of edge length 1.05 µm at 12 tube voltages. The fiber manufacturer created a graded index in the central region by varying the

Localization of Fe d-states in Ni-Fe-Cu alloys and implications for ultrafast demagnetization

October 20, 2018
Author(s)
Ronny J. Knut, Erna Delczeg, Justin Shaw, Hans Nembach, Patrik Grychtol, Dmitriy Zusin, Christian Gentry, Emrah Turgut, Henry C. Kapteyn, Margaret M. Murnane, Dario A. Arena, Olle Eriksson, Olof Karis, Thomas J. Silva
Ni 80Fe 20 (Py) and Py-Cu exhibit intriguing ultrafast demagnetization behavior, where the Ni magnetic moment shows a delayed response relative to the Fe [S. Mathias et al., PNAS \bf 109}, 4792 (2012)]. To unravel the mechanism responsible for this

PRIMARY STANDARDIZATION OF THE MASSIC ACTIVITY OF A PROTACTINIUM-233 SOLUTION

August 23, 2018
Author(s)
Ryan P. Fitzgerald, Leticia S. Pibida
Protactinium-233 (233Pa) is used as a tracer for radiochemical analysis and is of particular interest as an isotope dilution mass spectrometry (IDMS) spike for 231Pa/235U radio- chronometry. To this end, we present massic activity determinations by two

Dosimetric characterization of a new directional low-dose rate brachytherapy source

June 21, 2018
Author(s)
Michael G. Mitch, Larry A. DeWerd, Manik Aima, Clifford G. Hammer, Wesley S. Culberson
CivaTech Oncology Inc. (Durham, NC) has developed a novel low-dose rate (LDR) brachytherapy source called the CivaSheet. The source is a planar array of discrete elements (“CivaDots") which are directional in nature. This work investigates the

Precision determination of absolute neutron flux

June 8, 2018
Author(s)
Jeffrey S. Nico, Maynard S. Dewey, David M. Gilliam, Andrew T. Yue, Eamon Anderson, Geoff Greene, Alexander Laptev, William M. Snow
A technique for establishing the total neutron rate of a highly-collimated monochromatic cold neutron beam was demonstrated using the method of an alpha- gamma counter. The method requires only the counting of measured rates and is independent of neutron

Refined Calculations of Synchrotron Radiation for NISTs SURF III Facility

April 16, 2018
Author(s)
Eric L. Shirley, Mitchell L. Furst, Uwe Arp
We have developed a new method for exact calculation of synchrotron radiation for the National Institute of Standards and Technology Synchrotron Ultraviolet Radiation Facility, SURF III. Instead of using the Schwinger formula, which is only an

High-precision measurements of n = 2 - n = 1 transition energies and level widths in He- and Be- like Argon Ions

March 26, 2018
Author(s)
Jorge Machado, Csilla Szabo-Foster, Jose Paulo Santos, Pedro Amaro, Mauro Guerra, Guojie Bian, Jean-Michel Isac, Paul Indelicato
We have performed a reference-free measurement of the transition energies of the 1s2p1P1 → 1s2 1S0 line in He-like argon, and of the 1s2s22p 1P1 → 1s22s2 1S0 line in Be-like argon ions. The highly-charged ions were produced in the plasma of an Electron

Natural Uranium Radioactivity Solution Standard: SRM 4321d

December 27, 2017
Author(s)
Ronald Colle, Lizbeth Laureano-Perez, Svetlana Nour, Jerome J. LaRosa, Brian E. Zimmerman, Leticia S. Pibida, Denis E. Bergeron
A new natural uranium solution standard has been produced and will be disseminated by the National Institute of Standards and Technology (NIST) as Standard Reference Material 4321d. The standard is certified for the massic activities of 234U, 235U, and

Optically Polarized He3

November 30, 2017
Author(s)
Thomas R. Gentile, P.J. Nacher, B Saam, T G. Walker
This article reviews the physics and technology of producing large quantities fo highly spin- polarized, or hyderpolarized, He3 nuclei using spin-exchange (SEOP) and metastability-exchange (MEOP) optical pumping, and surveys applications of polarized He3

Neutron and X-ray Tomography (NeXT) system for simultaneous, dual modality tomography

November 27, 2017
Author(s)
Jacob M. LaManna, Daniel S. Hussey, Elias M. Baltic, David L. Jacobson
Dual mode tomography offers the potential of improved estimation of the composition of a sample from the complimentary of the interaction of the two probes with the sample. We have developed a simultaneous neutron and 90 keV X-ray tomography system that is

Results of an International Comparison of Activity Measurements of 68Ge

November 7, 2017
Author(s)
Jeffrey T. Cessna, Ryan P. Fitzgerald, Brian E. Zimmerman, Lizbeth Laureano-Perez, Denis E. Bergeron
An international key comparison, identifier CCRI(II)-K2.Ge-68, has been performed. The National Institute of Standards and Technology (NIST) served as the pilot laboratory, distributing aliquots of a 68Ge/68Ga solution. Results for the activity

HIGH EFFICIENCY CARBON NANOTUBE THREAD ANTENNAS

November 3, 2017
Author(s)
Christopher L. Holloway, Aydin Babajgabni, Chris Long, David R. Novotny, Nate Orloff, E. A. Bengio, Damir Senic, Lauren W. Taylor, Dimitri E. Tsentalovich
Although previous research has explored the underlying theory of high-frequency behavior of carbon nanotubes (CNTs) and CNT bundles for antennas, there is a gap in the literature for direct experimental measurements of radiation efficiency. These

Supplement 2 to the 2004 update of the AAPM Task Group No. 43 1 Report: Joint recommendations by the AAPM and GEC-ESTRO

September 30, 2017
Author(s)
Michael G. Mitch, Mark J. Rivard, Facundo Ballester, Wayne M. Butler, Larry A. DeWerd, Geoffrey S. Ibbott, Christopher Melhus
Since publication of the 2004 update to the American Association of Physicists in Medicine (AAPM) Task Group No. 43 Report (TG-43U1) and its 2007 supplement (TG-43U1S1), several new low- energy photon-emitting brachytherapy sources have become available
Was this page helpful?