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.

Search Publications by: Maynard S. Dewey (Fed)

Search Title, Abstract, Conference, Citation, Keyword or Author
Displaying 26 - 50 of 164

A gamma and X-ray dector for cryogenic, high magnetic field applications

July 13, 2012
Author(s)
Thomas R. Gentile, R L. Cooper, R. Alarcon, M J. Bales, E J. Beise, H Breuer, J. Byrne, T E. Chupp, Kevin J. Coakley, Maynard S. Dewey, Changbo Fu, Hans P. Mumm, Jeffrey S. Nico, B. O'Neill, K. Pulliam, Alan Keith Thompson, F E. Wietfeldt
As part of an experiment to measure the spectrum of photons emitted in beta-decay of the free neu- tron, we developed and operated a detector consisting of 12 bismuth germanate (BGO) crystals coupled to avalanche photodiodes (APDs). The detector was

An experiment for the precision measurement of the radiative decay mode of the neutron

October 5, 2009
Author(s)
R Cooper, Christopher D. Bass, E Beise, H Breuer, Jim Byrne, T E. Chupp, Kevin Coakley, Maynard S. Dewey, B Fisher, Changbo Fu, Thomas R. Gentile, M. McGonagle, Hans Pieter Mumm, Jeffrey S. Nico, Alan Keith Thompson, F E. Wietfeldt
The neutron typically beta decays into a proton, electron, and antineutrino. In some decays, it can be accompanied by a high energy photon. We recently performed the rst observation of the radiative beta decay branch for the free neutron with photons of

Prospects for a New Cold Neutron Beam Measurement of the Neutron Lifetime

October 5, 2009
Author(s)
Maynard S. Dewey, Kevin J. Coakley, David M. Gilliam, G. Greene, A. Laptev, Jeffrey S. Nico, William M. Snow, F. E. Wiefeldt, A. Yue
In the most accurate cold neutron beam determination of the neutron lifetime based on the absolute counting of decay protons, the largest uncertainty was attributed to the absolute determination of the capture flux of the cold neutron beam. Currently an

Measuring 6LI(N,T) and 10B(N,A) Cross Sections Using the NIST Alpha-Gamma Device

April 15, 2009
Author(s)
Maynard S. Dewey, David M. Gilliam, Jeffrey S. Nico, G.L. Green, A. Laptev, A. Yue
The 6LI(N,T) and 10B(N,A) cross sections are important neutron cross section standards. Precise knowledge of these cross sections is essential because they are often used as reference standards for obtaining the neutron fluence in investigations of the

Radiative Beta Decay of the Free Neutron

February 2, 2009
Author(s)
R L. Cooper, T E. Chupp, Maynard S. Dewey, Thomas R. Gentile, Hans Pieter Mumm, Jeffrey S. Nico, Alan Keith Thompson, B M. Fisher, I Kremsky, F E. Wietfeldt, E J. Beise, H Breuer, K G. Kiriluk, J Bryne, Kevin Coakley, Changbo Fu
The theory of quantum electrodynamics predicts that the beta decay of the neutron into a proton, electron, and antineutrino is accompanied by a continuous spectrum of emitted photons described as inner bremsstrahlung. While this phenomenon has been

Accurate Determination of High Energy Gamma-Ray Standards

October 16, 2008
Author(s)
Ernest G. Kessler Jr., Maynard S. Dewey, R Deslattes, Albert Henins, H G. Borner, M Jentschel, H Lehmann
The extension of accurate crystal diffraction spectroscopy to the 2 to 6 MeV region is described. Gamma-ray standards with a relative uncertainty of (2 to 5)x10 -7 are obtained by measuring the small diffraction angles (a few tenths of a degree) through

Precision Measurement of the 29 Si, 33 S, and 36 Cl Binding Energies

October 16, 2008
Author(s)
Maynard S. Dewey, Ernest G. Kessler Jr., R Deslattes, H G. Borner, M Jentschel, C Doll, P Mutti
The binding energies of 29Si, 33S, and 36Cl have been measured with a relative uncertainty 0.65 x 10 -6 using a flat-crystal spectrometer. The unique features of these measurements are 1) nearly perfect crystals whose lattice spacing is known in meters, 2

Particle and Photon Detection for a Neutron Radiative Decay Experiment

April 11, 2007
Author(s)
Thomas R. Gentile, Maynard S. Dewey, Hans P. Mumm, Jeffrey S. Nico, Alan K. Thompson, T E. Chupp, R Cooper, B M. Fisher, I Kremsky, F E. Wietfeldt, K G. Kiriluk, E Beise
We present the particle and photon detection methods employed in a program to observe neutron radiative beta-decay. The experiment is located at the NG-6 beam line at the National Institute of Standards and Technology Center for Neutron Research. Electrons

Observation of the Radiative Decay Mode of the Free Neutron

December 29, 2006
Author(s)
Jeffrey S. Nico, Maynard S. Dewey, Thomas R. Gentile, Hans P. Mumm, Alan K. Thompson, B Fisher, I Kremsky, Fred E. Wietfeldt, T E. Chupp, R Cooper, E Beise, K G. Kiriluk, J Byrne, Kevin J. Coakley
The theory of quantum electrodynamics predicts that beta decay of the neutron into a proton, electron, and antineutrino should be accompanied by a continuous spectrum of soft photons. While this inner bremsstrahlung branch has been previously measured in

Radiative Decay Mode of the Free Neutron

January 1, 2006
Author(s)
Jeffrey S. Nico, Maynard S. Dewey, Thomas R. Gentile, Hans P. Mumm, Alan K. Thompson, B M. Fisher, I Kremsky, Fred E. Wietfeldt, T E. Chupp, R L. Cooper, E J. Beise, K G. Kiriluk, J Byrne, K Coakley