R. J. Taylor
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Research Subjects
R. J. Taylor has a total of 162 co-authors. Here are the top co-authors by number of shared publications:
- Leendert Hayen
North Carolina State University
5 shared publications - August Mendelsohn
University of Manitoba
3 shared publications - Christopher B. Crawford
University of Kentucky
3 shared publications - Grant Riley
Los Alamos National Laboratory
3 shared publications - Leah J. Broussard
Oak Ridge National Laboratory
3 shared publications - Mark Makela
Los Alamos National Laboratory
3 shared publications
Latest Publications
- 10 August 2026
- Published by American Physical Society (APS) in Physical Review C
- Vol. 114 (2) , 025501
Characterization of low-energy ionization signals in silicon detectors for the Nab experiment
The Nab (Neutron a b) experiment is designed to measure the beta-antineutrino angular correlation in free neutron $\ensuremath{\beta}$ decay with an ultimate precision goal of 0.1%, providing input for tests of Cabibbo-Kobayashi-Maskawa matrix unitarity. This measurement is performed via detection of electrons and protons in delayed coincidence using custom large-area segmented silicon detectors. We present the characterization of one such detector system to establish the proton energy and timing response, using a dedicated proton accelerator. The detected proton peak was studied for 25, 30, and 35 keV incident protons on a set of detector segments and multiple cooling cycles over a one-year period. Ionization losses were consistent with models of the detector dead layer with thicknesses less than 100 nm. The detected proton peak was stable within the uncertainty from energy calibration (0.25 keV). The rise times of detector pulses from $^{109}\mathrm{Cd}$ and $^{113}\mathrm{Sn}$ conversion electron sources were used to extract the impurity density profile and establish a precise model for the detector timing response. The observed impurity density profile varied from $(2\ifmmode\pm\else\textpm\fi{}2)\ifmmode\times\else\texttimes\fi{}{10}^{9}/{\mathrm{cm}}^{3}$ at the center to $(26\ifmmode\pm\else\textpm\fi{}2)\ifmmode\times\else\texttimes\fi{}{10}^{9}/{\mathrm{cm}}^{3}$ at the edge. This impurity density profile was then used to characterize systematic effects in proton time-of-flight measurements due to detector pulse-shape effects; the resultant proton timing systematic uncertainties were below 0.3 ns, which is sufficient for the Nab experiment.- 10 August 2026
- Published by American Physical Society (APS) in Physical Review C
- Vol. 114 (2) , 025501
Characterization of low-energy ionization signals in silicon detectors for the Nab experiment
The Nab (Neutron a b) experiment is designed to measure the beta-antineutrino angular correlation in free neutron $\ensuremath{\beta}$ decay with an ultimate precision goal of 0.1%, providing input for tests of Cabibbo-Kobayashi-Maskawa matrix unitarity. This measurement is performed via detection of electrons and protons in delayed coincidence using custom large-area segmented silicon detectors. We present the characterization of one such detector system to establish the proton energy and timing response, using a dedicated proton accelerator. The detected proton peak was studied for 25, 30, and 35 keV incident protons on a set of detector segments and multiple cooling cycles over a one-year period. Ionization losses were consistent with models of the detector dead layer with thicknesses less than 100 nm. The detected proton peak was stable within the uncertainty from energy calibration (0.25 keV). The rise times of detector pulses from $^{109}\mathrm{Cd}$ and $^{113}\mathrm{Sn}$ conversion electron sources were used to extract the impurity density profile and establish a precise model for the detector timing response. The observed impurity density profile varied from $(2\ifmmode\pm\else\textpm\fi{}2)\ifmmode\times\else\texttimes\fi{}{10}^{9}/{\mathrm{cm}}^{3}$ at the center to $(26\ifmmode\pm\else\textpm\fi{}2)\ifmmode\times\else\texttimes\fi{}{10}^{9}/{\mathrm{cm}}^{3}$ at the edge. This impurity density profile was then used to characterize systematic effects in proton time-of-flight measurements due to detector pulse-shape effects; the resultant proton timing systematic uncertainties were below 0.3 ns, which is sufficient for the Nab experiment.- Open Access
- 4 March 2026
- Published by American Physical Society (APS) in Physical Review C
- Vol. 113 (3)
First full Dalitz plot measurement in neutron β decay using the Nab spectrometer and implications for new physics
Precision measurements of observables in neutron β decay are used to test the standard model description of the weak interaction and search for evidence of new physics. The Nab experiment at the Fundamental Neutron Physics Beamline at the Spallation Neutron Source was constructed to measure correlations in neutron decay by utilizing an asymmetric spectrometer and novel detection system to accurately reconstruct the proton momentum and electron energy for each β decay. This work describes the detection of neutron β -decay products in the Nab spectrometer and presents the first full Dalitz plot representation of the phase space of neutron β decay for all electrons > 100 keV. In addition, new constraints are placed on a possible excited neutron state, hypothesized to explain the disagreement between the appearance and disappearance neutron lifetime techniques.
- 4 March 2026
- Published by American Physical Society (APS) in Physical Review C
- Vol. 113 (3)
Open AccessFirst full Dalitz plot measurement in neutron β decay using the Nab spectrometer and implications for new physics
Precision measurements of observables in neutron β decay are used to test the standard model description of the weak interaction and search for evidence of new physics. The Nab experiment at the Fundamental Neutron Physics Beamline at the Spallation Neutron Source was constructed to measure correlations in neutron decay by utilizing an asymmetric spectrometer and novel detection system to accurately reconstruct the proton momentum and electron energy for each β decay. This work describes the detection of neutron β -decay products in the Nab spectrometer and presents the first full Dalitz plot representation of the phase space of neutron β decay for all electrons > 100 keV. In addition, new constraints are placed on a possible excited neutron state, hypothesized to explain the disagreement between the appearance and disappearance neutron lifetime techniques.
- Open Access
- 1 August 2024
- Published by IOP Publishing in New Journal of Physics
- Vol. 26 (8) , 083021
Larmor power limit for cyclotron radiation of relativistic particles in a waveguide
Cyclotron radiation emission spectroscopy (CRES) is a modern technique for high-precision energy spectroscopy, in which the energy of a charged particle in a magnetic field is measured via the frequency of the emitted cyclotron radiation. The He6-CRES collaboration aims to use CRES to probe beyond the standard model physics at the TeV scale by performing high-resolution and low-background beta-decay spectroscopy of 6 He and 19 Ne . Having demonstrated the first observation of individual, high-energy (0.1–2.5 MeV) positrons and electrons via their cyclotron radiation, the experiment provides a novel window into the radiation of relativistic charged particles in a waveguide via the time-derivative (slope) of the cyclotron radiation frequency, d f c / d t . We show that analytic predictions for the total cyclotron radiation power emitted by a charged particle in circular and rectangular waveguides are approximately consistent with the Larmor formula, each scaling with the Lorentz factor of the underlying e ± as γ 4. This hypothesis is corroborated with experimental CRES slope data.
- 1 August 2024
- Published by IOP Publishing in New Journal of Physics
- Vol. 26 (8) , 083021
Open AccessLarmor power limit for cyclotron radiation of relativistic particles in a waveguide
Cyclotron radiation emission spectroscopy (CRES) is a modern technique for high-precision energy spectroscopy, in which the energy of a charged particle in a magnetic field is measured via the frequency of the emitted cyclotron radiation. The He6-CRES collaboration aims to use CRES to probe beyond the standard model physics at the TeV scale by performing high-resolution and low-background beta-decay spectroscopy of 6 He and 19 Ne . Having demonstrated the first observation of individual, high-energy (0.1–2.5 MeV) positrons and electrons via their cyclotron radiation, the experiment provides a novel window into the radiation of relativistic charged particles in a waveguide via the time-derivative (slope) of the cyclotron radiation frequency, d f c / d t . We show that analytic predictions for the total cyclotron radiation power emitted by a charged particle in circular and rectangular waveguides are approximately consistent with the Larmor formula, each scaling with the Lorentz factor of the underlying e ± as γ 4. This hypothesis is corroborated with experimental CRES slope data.
- 23 August 2023
- Published by American Physical Society (APS) in Physical Review Letters
- Vol. 131 (8) , 082502
First Observation of Cyclotron Radiation from MeV-Scale following Nuclear DecayWe present an apparatus for detection of cyclotron radiation yielding a frequency-based kinetic energy determination in the 5 keV to 2.1 MeV range, characteristic of nuclear decays. The cyclotron frequency of the radiating particles in a magnetic field is used to determine the energy precisely. Our work establishes the foundation to apply the cyclotron radiation emission spectroscopy (CRES) technique, developed by the Project 8 Collaboration, far beyond the 18-keV tritium endpoint region. We report initial measurements of ’s from and ’s from decays to demonstrate the broadband response of our detection system and assess potential systematic uncertainties for spectroscopy over the full (MeV) energy range. To our knowledge, this is the first direct observation of cyclotron radiation from individual highly relativistic ’s in a waveguide. This work establishes the application of CRES to a variety of nuclei, opening its reach to searches for new physics beyond the TeV scale via precision -decay measurements.- 23 August 2023
- Published by American Physical Society (APS) in Physical Review Letters
- Vol. 131 (8) , 082502
First Observation of Cyclotron Radiation from MeV-Scale following Nuclear DecayWe present an apparatus for detection of cyclotron radiation yielding a frequency-based kinetic energy determination in the 5 keV to 2.1 MeV range, characteristic of nuclear decays. The cyclotron frequency of the radiating particles in a magnetic field is used to determine the energy precisely. Our work establishes the foundation to apply the cyclotron radiation emission spectroscopy (CRES) technique, developed by the Project 8 Collaboration, far beyond the 18-keV tritium endpoint region. We report initial measurements of ’s from and ’s from decays to demonstrate the broadband response of our detection system and assess potential systematic uncertainties for spectroscopy over the full (MeV) energy range. To our knowledge, this is the first direct observation of cyclotron radiation from individual highly relativistic ’s in a waveguide. This work establishes the application of CRES to a variety of nuclei, opening its reach to searches for new physics beyond the TeV scale via precision -decay measurements.- 27 June 2023
- Published by American Physical Society (APS) in Physical Review C
- Vol. 107 (6) , 065503
Precision pulse shape simulation for proton detection at the Nab experiment
The Nab experiment at Oak Ridge National Laboratory, USA, aims to measure the beta-antineutrino angular correlation following neutron decay to an anticipated precision of approximately 0.1%. The proton momentum is reconstructed through proton time-of-flight measurements, and potential systematic biases in the timing reconstruction due to detector effects must be controlled at the nanosecond level. We present a thorough and detailed semiconductor and quasiparticle transport simulation effort to provide precise pulse shapes, and report on relevant systematic effects and potential measurement schemes.- 27 June 2023
- Published by American Physical Society (APS) in Physical Review C
- Vol. 107 (6) , 065503
Precision pulse shape simulation for proton detection at the Nab experiment
The Nab experiment at Oak Ridge National Laboratory, USA, aims to measure the beta-antineutrino angular correlation following neutron decay to an anticipated precision of approximately 0.1%. The proton momentum is reconstructed through proton time-of-flight measurements, and potential systematic biases in the timing reconstruction due to detector effects must be controlled at the nanosecond level. We present a thorough and detailed semiconductor and quasiparticle transport simulation effort to provide precise pulse shapes, and report on relevant systematic effects and potential measurement schemes.