Large-mass ultralow noise germanium detectors: performance and applications in neutrino and astroparticle physics

Abstract

A new type of radiation detector, a p-type modified electrode germanium diode, is presented. The prototype displays, for the first time, a combination of features (mass, energy threshold and background expectation) required for a measurement of coherent neutrino-nucleus scattering in a nuclear reactor experiment. The device hybridizes the mass and energy resolution of a conventional HPGe coaxial gamma spectrometer with the low electronic noise and threshold of a small x-ray semiconductor detector, also displaying an intrinsic ability to distinguish multiple from single-site particle interactions. The present performance of the prototype and possible further improvements are discussed, as well as other applications for this new type of device in neutrino and astroparticle physics (double-beta decay, neutrino magnetic moment and WIMP searches).PACS numbers: 85.30. De, 95.35.+d, 13.15.+g, 25.30.Pt, 95.55.Vj,

Arrival time and magnitude of airborne fission products from the Fukushima, Japan, reactor incident as measured in Seattle, WA, USA

“…This allows us to sample ∼10 times more air than what had been done previously here at the university after the Chernobyl incident (Kellogg et al, 1986) and proved to be one of the key points for the successful detection of the radioactive fission products. In order to search for characteristic gamma rays stemming from radionuclides we place the samples inside a lead shield of 5 to 20 cm thickness next to a 0.5-kg ptype point contact germanium detector (Barbeau et al, 2007) for low-level counting. The detector exhibits an energy resolution of 1.4 keV FWHM at 600 keV.…”

Ionization efficiency study for low energy nuclear recoils in germanium

“…Utilizing thermal neutrons requires the full absorption of out-going gamma rays measured by another detector in coincidence. Without this additional measurement, Compton scattering from out-going gamma rays within [5,6,7,8,9,10,11,12,13].…”

Probing nonstandard interactions with reactor neutrinos

“…We would like to note that currently there are other experimental proposals [20], which are not covered by our analysis.…”