Abstract. The most sensitive direct method to establish the absolute neutrino mass is observation of the endpoint of the tritium beta-decay spectrum. Cyclotron Radiation Emission Spectroscopy (CRES) is a precision spectrographic technique that can probe much of the unexplored neutrino mass range with O(eV) resolution. A lower bound of m(ν e ) 9(0.1) meV is set by observations of neutrino oscillations, while the KATRIN Experiment -the current-generation tritium beta-decay experiment that is based on Magnetic Adiabatic Collimation with an Electrostatic (MAC-E) filter -will achieve a arXiv:1703.02037v1 [physics.ins-det]

It has been understood since 1897 that accelerating charges must emit electromagnetic radiation. Although first derived in 1904, cyclotron radiation from a single electron orbiting in a magnetic field has never been observed directly. We demonstrate single-electron detection in a novel radio-frequency spectrometer. The relativistic shift in the cyclotron frequency permits a precise electron energy measurement. Precise beta electron spectroscopy from gaseous radiation sources is a key technique in modern efforts to measure the neutrino mass via the tritium decay end point, and this work demonstrates a fundamentally new approach to precision beta spectroscopy for future neutrino mass experiments. For over a century, nuclear decay electron spectroscopy has played a pivotal role in the understanding of nuclear physics. Early measurements of the continuous β-decay spectrum [1] provided the first evidence of the existence of the weak force and the neutrino [2], and immediately hinted that the neutrino mass is small. Continuing this tradition, present efforts to directly measure the mass of the neutrino rely on precision spectroscopy of the β-decay energy spectrum of 3 H. Because the value of the neutrino mass is an input to the standard model of particle physics as well as precision cosmology, a precision measurement of the neutrino mass would represent a significant advance in our description of nature.The sensitivity of 3 H -based neutrino mass measurements has been improving over the past 80 years as a result of increasingly powerful electron spectrometry techniques [3][4][5][6]. The most sensitive experiments to date place a limit on the electron-flavor-weighted neutrino mass m β ≤ 2.05 eV=c 2 at 95% C.L. [7][8][9], m 2 β ¼

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The recently developed technique of Cyclotron Radiation Emission Spectroscopy (CRES) uses frequency information from the cyclotron motion of an electron in a magnetic bottle to infer its kinetic energy. Here we derive the expected radio frequency signal from an electron in a waveguide CRES apparatus from first principles. We demonstrate that the frequency-domain signal is rich in information about the electron's kinematic parameters, and extract a set of measurables that in a suitably designed system are sufficient for disentangling the electron's kinetic energy from the rest of its kinematic features. This lays the groundwork for high-resolution energy measurements in future CRES experiments, such as the Project 8 neutrino mass measurement.

This milestone report presents an update on the state-of-the-art review and research being conducted to identify key indicators of cable aging at nuclear power plants (NPPs), and devise in-situ measurement techniques that are sensitive to these key indicators. The motivation for this study stems from the need to address open questions related to nondestructive evaluation (NDE) of aging cables for degradation detection and estimation of condition-based remaining service life. These questions arise within the context of a second round of license extension for NPPs that would extend the operating license from 60 to 80 years. Within the introduction, a review of recent published U.S. and international research and guidance for cable aging management programs including NDE technologies is provided. As with any "state-of-the-art" report, the observations are deemed accurate as of the publication date but cannot anticipate evolution of the technology. Moreover, readers are advised that research and development of cable NDE technology is an ongoing issue of global concern.Cable safety factors offer significant margin for normal operation and consequently most cables can be expected to perform satisfactorily under normal loads. Cables are inherently tested as part of the regular system tests that are periodically performed on nuclear plant systems and active components. As emphasized in Regulatory Guide 1.128, the cable aging management program focuses on the ability of a cable to withstand extreme stresses such as in a design-basis event (DBE) that may not be addressed with normal system tests. Degradation of the electrical insulation and other cable components are key issues that are likely to affect the ability of the currently installed cables to operate safely and reliably under a DBE for another 20 to 40 years beyond the initial qualified operating life. With more than 1000 km of power, control, instrumentation, and other cables typically found in a NPP, it would be a daunting undertaking to inspect all of the cables. Practical guidelines, however, have been developed and are evolving that offer a manageable approach to sampling and screening cables based on accessibility, risk, history, and other factors. Moreover, the range of cables and conditions plus today's state of the art does not support a single test to assure the cable's function. Rather, a range of testing tools must be applied to manage the cable aging concerns and assure that degraded cables are repaired or replaced prior to the end of their safe operating life. Cable aging management program recommendations include a database of cables selected for test and trending including the required appropriate cable test based on accessibility, risk, and environment. Such tests include bulk electrical characteristic measurements that can be made from the cable ends and, in some cases, locate the weak portion of the cable as well as local tests to confirm insulation condition and provide guidance to predict remaining available safe life.The Pacific Northwest Nat...