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Displaying 201 - 225 of 244

Measuring the Neutron Lifetime Using Magnetically Trapped Neutrons

May 1, 2014
Author(s)
Hans P. Mumm, Alan Keith Thompson, Paul R. Huffman, Christopher O'Shaughnessy, Kevin J. Coakley, Robert Golub, John M. Doyle, Steve K. Lamoreaux, P.-N. Seo, C E. Mattoni, S N. Dzhosyuk, L Yang, Grace L. Yang, Karl W. Schelhammer, Christopher M. Swank
The neutron beta-decay lifetime plays an important role, both in understanding weak interactions within the framework of the Standard Model, and in theoretical predictions of the primordial abundance of 4He in Big Bang Nucleosynthesis. In previous work, we

Results of an international comparison for the activity measurement of 177Lu

March 6, 2012
Author(s)
Brian E. Zimmerman, Denis E. Bergeron, Jeffrey T. Cessna
An international Key Comparison of 177Lu has recently been carried out. Twelve laboratories performed assays for radioactivity content on aliquots of a common master solution of 177Lu, leading to eleven results submitted for entry into the Key Comparison

NIST Ionization Chamber "A" Sample-Height Corrections

February 2, 2012
Author(s)
Ryan P. Fitzgerald
For over 30 years scientists in the NIST radioactivity group have been using their ionization chamber “A” to make measurements of radioactivity and radioactive half-lives. We now have evidence that some of those reported measurements were incorrect due to

Polarized neutron beam properties for measuring parity-violating spin rotation in liquid He4

December 14, 2010
Author(s)
A M. Micherdzinska, C. D. Bass, T. D. Bass, K. F. Gan, D Lou, D M. Markoff, Hans Pieter Mumm, Jeffrey S. Nico, A. K. Opper, E I. Sharapov, M Snow, H E. Swanson, V Zhumabekova
Measurements of parity-violating neutron spin rotation can provide insight into the poorly nderstood nucleon-nucleon weak interaction. Because the expected rotation angle per unit length is small (10−7 rad/m), several properties of the polarized cold

Nuclear Magnetic Resonance Gyroscopes

November 2, 2010
Author(s)
Elizabeth A. Donley
Nuclear magnetic resonance gyroscopes(NMRGs)detect rotation as shift in the Larmor precession frequency of nuclear spins. A review of the open literature on NMRGs is presented, which includes an introduction to the spectroscopic techniques that enable

Resonance Strength in 22Ne(p,gamma)23Na from Depth Profiling in Aluminum

April 30, 2010
Author(s)
R Longland, C. Iliadis, J. Cesaratto, A E. Champagne, S Daigle, J.R. Newton, Ryan P. Fitzgerald
The novel method for extracting absolute resonance strengths has been investigated. By implanting 22Ne ions into a thick aluminum backing, and simultaneously measuring the 22Ne + p and 27Al+p reactions, the strength of the Elab,r = 479 keV resonance in
Displaying 201 - 225 of 244