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The detection efficiency for large area alpha sources with adjustable heights of a raised lip around the edge were measured by 2π gas-filled proportional counter. The variations in low- energy spectral shape were modeled using a Geant4 radiation and charge
A key comparison has been made between the air-kerma standards of the NIST, USA and the BIPM in the medium-energy x ray range. The results show the standards to be in agreement at the level of the standard uncertainty of the comparison of 3.8 parts in 103
Leticia S. Pibida, Brian E. Zimmerman, Denis E. Bergeron, Ryan P. Fitzgerald, Jeffrey T. Cessna, Lynne E. King
The National Institute of Standards and Technology (NIST) performed new standardization measurements for 64Cu. As part of this work the photon emission probabilities for the main gamma-rays and the half-life were determined using several high purity
Understanding the changes in the microstructures and structures of clays with varying intercalated metal ions at elevated temperatures is of importance for many applications ranging from engineering materials such as ceramics for fuel cell applications to
Marcus H. Mendenhall, Albert Henins, Lawrence T. Hudson, Csilla I. Szabo-Foster, Donald A. Windover, James P. Cline
The structure of the x-ray emission lines of the Cu Kα complex has been remeasured on a newly commissioned instrument, in a manner directly traceable to the Système Internationale definition of the meter. In this measurement, the region from 8000 to 8100
Alexander Yulaev, Hongxuan Guo, Evgheni Strelcov, Lei Chen, Ivan Vlasssiouk, Andrei Kolmakov
An atomic-scale thickness, molecular impermeability, low atomic number, and mechanical strength make graphene an ideal electron transparent membrane for scanning electron microscopy and spectroscopy in liquids. Here, we present a novel sample platform made
Fan Zhang, Andrew J. Allen, Lyle E. Levine, De-Hao Tsai, Jan Ilavsky
We present an experimental study of the structural and dynamical properties of bimodal, micrometer-sized colloidal dispersions (size ratio ≈ 2) in an aqueous solution of low-molecular weight polymer (polyethylene glycol 2000) using synchrotron ultra-small
Hongxuan Guo, Evgheni Strelcov, Alexander Yulaev, Jian Wang, Narayana Appathurai, Stephen Urquhart, John Vinson, Subin Sahu, Michael P. Zwolak, Andrei Kolmakov
Photoelectron emission microscopy (PEEM) is a powerful tool to spectroscopically access dynamic surface processes at the nanoscale but is traditionally limited to ultra-high or moderate vacuum conditions. Here, we develop a novel graphene-capped
Those readers who have a library with the first bound copies of ARI may find it enjoyable to compare Volume 1, No.1 from 1956 with an issue from Volume 118 in 2016. The range of applications has shifted away from agricultural and industrial uses of
Cedric J. Powell, Aleksander Jablonski, Francesc Salvat, Angela Y. Lee
Version 4.0 of this database (SRD 64) provides values of differential elastic-scattering cross sections, total elastic-scattering cross sections, phase shifts, and transport cross sections for elements with atomic numbers from 1 to 96 and for electron
Cedric J. Powell, B Da, Shigeo Tanuma, H. Yoshikawa, H Shinotsuka, David R. Penn
We calculated electron inelastic mean free paths (IMFPs) for liquid water from its optical energy-loss function (ELF) for electron energies from 50 eV to 30 keV with the relativistic full Penn algorithm (FPA) that has been used for previous IMFP and
Lee J. Richter, Jonathan Downing, Sebastian Engmann, Hyun W. Ro, Andrew A. Herzing, Dean M. DeLongchamp, Subhrangsu Mukherjee, Harald Ade, Maged Addelsamie, Aram Amassian, Yuhang Liu, He Yan
Solution processing via roll-to-roll (R2R) coating promises a low cost, low thermal-budget, sustainable revolution for the production of solar cells. Yet virtually all high performance solution processed research cells have been demonstrated by spin
We propose a standard data format for the interchange of XAFS data. The XAFS Data Interchange (XDI) standard is meant to encapsulate a single spectrum of XAFS along with relevant metadata. XDI is a text-based format with a simple syntax which clearly
Lawrence T. Hudson, John F. Seely, Nino R. Pereira, H. Chen, G.J. Williams, R.P. Drake, C.C. Kuranz, C.A. Di Stefano, J. Park
Experiments were performed at the LLNL Titan laser to measure the propagation direction of the energetic electrons that were generated during the interaction of the polarized laser beam with solid targets in the case of normal incidence. The energetic
A new beamline is being commissioned at the Synchrotron Ultraviolet Radiation Facility (SURF III) on the Gaithersburg, MD campus of the National Institute of Standards and Technology (NIST). SURF III is a 380-MeV synchrotron radiation source providing
We analyzed calculated cross sections for K-, L-, and M-shell ionization by electron impact to determine the energy ranges over which these cross sections are consistent with the Bethe equation for inner-shell ionization. Our analysis was performed with K
Michael G. Huber, Muhammad D. Arif, David G. Cory, R. Haun, B. Heacock, Joachim Nsofini, Dimitry A. Pushin, P Saggu, C.B Shahi, William M. Snow, A.R. Young
The physical origin of the dark energy which causes the accelerated expansion rate of the universe is one of the major open questions of cosmology. One set of theories postulates the existence of a self-interacting scalar eld for dark energy coupling to
In response to the CIPM MRA, and to improve radioactivity measurements in the face of advancing technologies, the CIPMs consultative committee on ionizing radiation developed a strategic approach to the realization and validation of measurement
Eliot Gann, Brian A. Collins, Maolong Tang, John R. Tumbleston, Subhrangsu Mukherjee, Harald W. Ade
Anisotropic scattering patterns have been observed from organic thin films that are isotropic on the scale of the probe in polarized resonant X-ray scattering experiments. The symmetry is broken by local correlations between molecular orientation and
Young Il Joe, Galen C. O'Neil, Luis Miaja Avila, Joseph W. Fowler, Kevin L. Silverman, Daniel S. Swetz, Joel N. Ullom, Ralph Jimenez
X-ray emission spectroscopy (XES) is a powerful probe of the electronic and chemical state of elemental species embedded within more complex compounds. X-ray sensors that combine high resolving power and high collecting efficiency are desirable for photon
Charles S. Tarrio, Robert F. Berg, Thomas B. Lucatorto, Bruce Lairson, Heidi Lopez, Travis Ayers
We investigated several types of thin-film filters for high intensity work in the extreme-ultraviolet (EUV) spectral range. In our application, with a peak EUV intensity of 2.7 W cm-2, Ni-mesh-backed Zr filters have a typical lifetime of 20 hours, at which
Biogeochemical transformations of plant-derived soil organic matter (SOM) involve complex abiotic and microbially mediated reactions. One such reaction is halogenation, which occurs naturally in the soil environment and has been associated with enzymatic
Justin M. Shaw, Daniel Hickstein, Franklin Dollar, Patrik Grychtol, Jennifer Ellis, Carlos Hernandez-Garcia, Ronny J. Knut, Christian Gentry, Henry Kapteyn, Margaret Murnane
We generate ultrashort pulses of angularly isolated, circularly polarized extreme ultraviolet (EUV) light through the first implementation of noncollinear high harmonic generation with circularly polarized driving lasers. The noncollinear geometry offers