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Search Publications by: Jeffrey S. Nico (Fed)

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Displaying 1 - 25 of 81

Recoil-Order and Radiative Corrections to the aCORN Experiment

July 8, 2024
Author(s)
Maynard Dewey, Jeffrey Nico, Fred Wietfeldt
The aCORN experiment measures the electron-antineutrino a-coefficient in free neutron decay. We update the previous aCORN results to include radiative and recoil corrections to first order. The corrected combined result is a = -0.10859 +/- 0.00125 (stat) +

Comment on "Search for explanation of the neutron lifetime anomaly"

June 23, 2023
Author(s)
Fred Wietfeldt, Ripan Biswas, Jimmy Caylor, Bret Crawford, Maynard Dewey, Nadia Fomin, Geoffrey Greene, Christopher Haddock, Shannon Hoogerheide, Hans Mumm, Jeffrey Nico, William Snow, Joseph Zuchegno
We respond to issues raised by Serebrov et al. in a recent paper regarding systematic effects in the beam neutron lifetime experiment performed at NIST. We show that these effects were considered in the original analyses and that our corrections and

Results from the Baksan Experiment on Sterile Transitions (BEST)

June 9, 2022
Author(s)
Jeffrey S. Nico, V Barinov, Bruce Cleveland, S Danshin, H Ejiri, Steve Elliott, D Frekers, Vladimir Gavrin, Valery Gorbachev, D Gorbunov, Wick Haxton, Tanya Ibragimova, I Kim, Yu Kozlova, L Kravchuk, V Kuzminov, B Lubsandorzhiev, Yu Malyshkin, R Massarczyk, Victor Matveev, Ilya Mirmov, A Petelin, R Robertson, D Sinclair, A Shikhin, V Tarasov, G Trubnikov, E Veretenkin, John Wilkerson, A Zvir
The Baksan Experiment on Sterile Transitions (BEST) was designed to investigate the deficit of electron neutrinos, nu_e, observed in previous gallium-based radiochemical measurements with high-intensity neutrino sources, commonly referred to as the gallium

Search for electron-neutrino transitions to sterile states in the BEST experiment

June 9, 2022
Author(s)
Jeffrey S. Nico, V. Barinov, S.N. Danshin, V.N. Gavrin, V.V. Gorbachev, D.S. Gorbunov, T.V. Ibragimova, Yu.P. Kozlova, L.V. Kravchuk, V.V. Kuzminov, B.K. Lubsandorzhiev, Yu.M. Malyshkin, I.N. Mirmov, A.A. Shikhin, E.P. Veretenkin, B.T. Cleveland, H. Ejiri, S.R. Elliott, I. Kim, R. Massarczyk, D. Frekers, W.C. Haxton, V.A. Matveev, G.V. Trubnikov, A.L. Petelin, V.A. Tarasov, A.I. Zvir, R.G.H. Robertson, D. Sinclair, J.F. Wilkerson
The Baksan Experiment on Sterile Transitions (BEST) probes the gallium anomaly and its possible connections to oscillations between active and sterile neutrinos. Based on the Gallium- Germanium Neutrino Telescope (GGNT) technology of the SAGE experiment

Progress on the BL2 beam measurement of the neutron lifetime

April 17, 2021
Author(s)
Shannon M. Hoogerheide, Jimmy P. Caylor, Evan R. Adamek, Eamon S. Anderson, Ripan Biswas, B. E. Crawford, Christina DeAngelis, Maynard S. Dewey, N Fomin, David M. Gilliam, Kyle Grammer, G L. Greene, Robert W. Haun, Jonathan Mulholland, Hans Pieter Mumm, Jeffrey S. Nico, William M. Snow, F E. Wietfeldt, Andrew Yue
A precise value of the neutron lifetime is important in several areas of physics, including determinations of the quark-mixing matrix element |Vud|, related tests of the Standard Model, and predictions of light element abundances in Big Bang

Neutron Spin Rotation Measurements

April 15, 2021
Author(s)
Jeffrey S. Nico, Shannon Hoogerheide, Hans Pieter Mumm, Murad Sarsour, J Amadio, Eamon Anderson, Libertad Barron-Palos, Bret Crawford, Chris Crawford, D. Esposito, Walter Fox, I Francis, J Fry, Chris Haddock, Adam Holley, Kirill Korsak, J Lieers, S Magers, M. Maldonado-Velazquez, D Mayorov, T Okudaira, C Paudel, S Santra, H.M. Shimizu, William M. Snow, A. Sprow, K. Steen, H E. Swanson, John Vanderwerp, P. A. Yergeau
The neutron spin rotation (NSR) collaboration used parity-violating spin rotation of transversely polarized neutrons transmitted through a 0.5 m liquid helium target to constrain weak coupling constants between nucleons. While consistent with theoretical

Position-dependent neutron detection efficiency loss in 3He gas proportional counters

August 22, 2020
Author(s)
Patrick N. Peplowski, Zachary W. Yokley, Madison Liebel, Shuo Cheng, Richard C. Elphic, Shannon Hoogerheide, David J. Lawrence, Jeffrey Nico
The position-dependent neutron detection response of a 3He gas proportional counter (GPC) was characterized using a collimated (3-mm-wide), monoenergetic 0.05 eV neutron beam. For neutrons incident on the GPC near the ends of the active region, the neutron

Experimental Upper Bound and Theoretical Expectations for Parity-Violating Neutron Spin Rotation in He-4

July 16, 2019
Author(s)
Jeffrey S. Nico, Hans P. Mumm, H E. Swanson, C. D. Bass, T. D. Bass, J M. Dawkins, J C. Horton, D Luo, William M. Snow, S. C. Walbridge, B. E. Crawford, K. F. Gan, A M. Micherdzinska, C. R. Huffer, D M. Markoff, Murad Sarsour, E I. Sharapov, V Zhumabekova, Blayne R. Heckel
Neutron spin rotation is expected from quark-quark weak interactions in the Standard Model, which induce weak interactions among nucleons that violate parity. We present the results from an experiment searching for the effect of parity violation via 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

aCORN: an experiment to measure the electron-antineutrino correlation coefficient in free neutron decay

August 1, 2017
Author(s)
Maynard S. Dewey, Fred B. Bateman, Wangchun Chen, Thomas R. Gentile, Md. T. Hassan, Michael P. Mendenhall, Jeffrey S. Nico, Brian Collett, Jim Byrne, William Byron, Guillaume Darius, Christina DeAngelis, Gordon L. Jones, Alexander Komives, Alexander Laptev, George Noid, Hyeonseo Park, Ed Stephenson, I Stern, K Stockton, Bob Trull, Fred Wietfeldt, B G. Yerozolimsky
We describe an apparatus used to measure the electron-neutrino angular correlation coefficient, a, in free neutron decay. The apparatus employs a novel measurement technique in which the angular correlation is converted into a proton time-of-flight

A Backscatter-Suppressed Beta Spectrometer

June 16, 2017
Author(s)
Maynard S. Dewey, Taufique Hassan, Fred B. Bateman, Brian Collett, Guillaume Darius, Christina DeAngelis, Gordon L. Jones, Alexander Komives, Alexander Laptev, Michael Mendenhall, Jeffrey S. Nico, George Noid, Ed Stephenson, Fred Wietfeldt, Isaac Stern, Bob Trull
Backscatter of electrons from a beta spectrometer, with incomplete energy deposition, can lead to undesirable effects in many types of experiments. We present and discuss the design and operation of a backscatter-suppressed beta spectrometer that was

Precision measurement of the radiative beta decay of the free neutron

June 14, 2016
Author(s)
Jeffrey S. Nico, Kevin J. Coakley, Maynard S. Dewey, Thomas R. Gentile, Hans P. Mumm, Alan Keith Thompson, M J. Bales, R. Alarcon, C. D. Bass, E J. Beise, H Breuer, Jim Byrne, R L. Cooper, B. O'Neill, F E. Wietfeldt, T E. Chupp
The theory of quantum electrodynamics predicts that a continuous spectrum of photons is emitted in the beta decay of the free neutron in addition to a proton, an electron, and an antineutrino. We report the first precision test of the shape of the photon

Nonproportionality in the scintillation light yield of bismuth germanate

November 11, 2014
Author(s)
Thomas R. Gentile, M J. Bales, H Breuer, T E. Chupp, Kevin J. Coakley, R L. Cooper, Jeffrey S. Nico, B. O'Neill
We present measurements of nonproportionality in the scintillation light yield of bismuth germanate (BGO) for gamma-rays with energies between 6 keV and 662 keV. The scintillation light was read out by avalanche photodiodes (APDs) with both the BGO

Fast Neutron Detection with a Segmented Spectrometer

November 3, 2014
Author(s)
Jeffrey S. Nico, T J. Langford, Christopher D. Bass, H Breuer, Craig Heimbach, D. K. Erwin
A fast neutron spectrometer consisting of segmented plastic scintillator and He-3 proportional counters was constructed for the measurement of neutrons in the energy range 1 MeV to 200 MeV. We discuss its design, principles of operation, and the method of

International Key Comparison of Neutron Fluence Measurements in Monoenergetic Neutron Fields – CCRI(III)-K11

November 3, 2014
Author(s)
Maynard S. Dewey, V. Gressier, A. C. Bonaldi, David M. Gilliam, H. Harano, A. Masuda, T Matsumoto, N. Moiseev, Jeffrey S. Nico, R. Notle, S. Oberstedt, N. J. Roberts, S. Rottger, D. J. Thomas
To ensure the validity of their national standards, National Metrology Institutes, NMIs, participate regularly in international comparisons. In the area of neutron metrology, Section III of the Consultative Committee for Ionizing Radiation is in charge of

Significant disparity in base and sugar damage in DNA by neutron and electron irradiation

July 1, 2014
Author(s)
Pawel Jaruga, Jeffrey S. Nico, Lisa R. Karam, Olga Timofeeva, William Blakely, M Miral Dizdar, D Pang
In this study a comparison of the effects of high-LET neutrons with low-LET electrons on irradiation of aqueous DNA solutions was investigated to characterize for potential neutron signatures on DNA damage induction. Ionizing radiations generate numerous

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

Event Identification in He-3 Proportional Counters Using Risetime Discrimination

April 2, 2013
Author(s)
Jeffrey S. Nico, T J. Langford, Christopher D. Bass, E J. Beise, D. K. Erwin, Craig Heimbach
We present a straightforward method for particle identification and background rejection in He-3 proportional counters for use in neutron detection. By measuring the risetime and pulse height of the preamplifier signals, one may define a region in the

Search for a T-odd, P-even Triple Correlation in Neutron Decay

September 14, 2012
Author(s)
Jeffrey S. Nico, T E. Chupp, K P. Coulter, R L. Cooper, S. J. Freeman, B. K. Fujikawa, A. Garcia, Gordon L. Jones, Hans P. Mumm, Alan K. Thompson, C A. Trull, F. E. Wiefeldt, J. F. Wilkerson
Time-reversal-invariance (T) violation, or equivalently, assuming charge-conjugation-parity-time-reversal (CPT) invariance, CP violation may explain the observed cosmological baryon asymmetry as well as signal physics beyond the Standard Model. In the

A New Limit on Time-Reversal Violation in Beta Decay

September 2, 2012
Author(s)
Hans P. Mumm, T E. Chupp, K P. Coulter, R L. Cooper, S J. Freedman, B. K. Fujikawa, A. Garcia, Gordon L. Jones, Jeffrey S. Nico, Alan K. Thompson, C A. Trull, J. F. Wilkerson, F. E. Wiefeldt
We report the results of an improved determination of the triple correlation DP • (p_e × p_v) that can be used to limit possible time-reversal invariance in the beta decay of polarized neutrons and constrain extensions to the Standard Model. Our result is

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

Magnetic field effects on large area avalanche photodiodes at cryogenic temperatures

August 30, 2011
Author(s)
Thomas R. Gentile, C. D. Bass, Jeffrey S. Nico, H Breuer, R Farrell
We present results for detection of X-rays by large area avalanche photodiodes (APDs) in strong magnetic fields and at cryogenic temperatures. Whereas at room temperature we observe essentially no effects on the response, at cryogenic temperature we