Related papers: High-Precision Excited-State Nuclear Recoil Spectr…
The BeEST experiment is searching for sub-MeV sterile neutrinos by measuring nuclear recoil energies from the decay of $^7$Be implanted into superconducting tunnel junction (STJ) sensors. The recoil spectra are affected by interactions…
Precision measurements of nuclear $\beta$ decay are among the most sensitive methods to probe beyond Standard Model (BSM) physics in the neutrino sector. In particular, momentum conservation between the emitted decay products in the final…
The response of Superheated Superconducting Granule (SSG) devices to nuclear recoils has been explored by irradiating SSG detectors with a 70Me$\!$V neutron beam. In the past we have tested Al SSG and more recently, measurements have been…
This work is part of an ongoing project to develop a Superheated Superconducting Granule (SSG) detector for cold dark matter and neutrinos. The response of SSG devices to nuclear recoils has been explored irradiating SSG detectors with a…
Superconducting tunnel junctions (STJs) are able to measure the energy of single photons in the range from near infrared to X-rays. They provide simultaneous information of the impact time and wavelength of an absorbed photon. The main…
We report a high-statistics measurement of the $L/K$ orbital electron capture (EC) ratio in $^7$Be embedded in cryogenic Ta. The thin Ta film formed part of a high-resolution superconducting tunnel junction (STJ) radiation detector that was…
Sterile neutrinos are natural extensions to the standard model of particle physics and provide a possible portal to the dark sector. We report a new search for the existence of sub-MeV sterile neutrinos using the decay-momentum…
Coherent elastic neutrino-nucleus scattering and low-mass Dark Matter detectors rely crucially on the understanding of their response to nuclear recoils. We report the first observation of a nuclear recoil peak at around 112 eV induced by…
The Beryllium Electron capture in Superconducting Tunnel junctions (BeEST) experiment searches for evidence of heavy neutrino mass eigenstates in the nuclear electron capture decay of $^7$Be by precisely measuring the recoil energy of the…
We report a measurement of the ionization efficiency of silicon nuclei recoiling with sub-keV kinetic energy in the bulk silicon of a charge-coupled device (CCD). Nuclear recoils are produced by low-energy neutrons ($<$24 keV) from a…
Superconducting Tunnel Junctions (STJs) are used as high-resolution quantum sensors to search for evidence of sterile neutrinos in the electron capture decay of $^7$Be. We are developing spatially-resolved Monte-Carlo simulations of the…
The Beryllium Electron capture in Superconducting Tunnel junctions (BeEST) experiment uses superconducting tunnel junction (STJ) sensors to search for physics beyond the standard model (BSM) with recoil spectroscopy of the $\mathbf{^7}$Be…
Superconducting Tunnel Junctions (STJ's) are currently being developed as photon detectors for a wide range of applications. Interest comes from their ability to cumulate photon counting with chromaticity (i.e. energy resolution) from the…
In this study, we have developed a new sub-MeV neutron detector that has a high position resolution, energy resolution, directional sensitivity, and low background. The detector is based on a super-fine-grained nuclear emulsion, called the…
We consider direct-detection searches for sub-GeV dark matter via electron scatterings in the presence of large interactions between dark and ordinary matter. Scatterings both on electrons and nuclei in the Earth's crust, atmosphere, and…
There are recent interests with CsI(Tl) scintillating crystals for Dark Matter experiments. The scattering signatures by neutrons on a CsI(Tl) detector were studied using a neutron beam generated by a 13 MV Tandem accelerator. The energy…
Directional detection of nuclear recoils is broadly desirable in nuclear and particle physics. At low recoil energies, this capability may be used to confirm the cosmological origin of a dark matter signal, to penetrate the so-called…
Nuclear reactors represent a promising neutrino source for CE$\nu$NS (coherent-elastic neutrino-nucleus scattering) searches. However, reactor sites also come with high ambient neutron flux. Neutron capture-induced nuclear recoils can…
Low-energy nuclear recoils (NRs) are hard to measure because they produce few e$^{-}$/h$^+$ pairs in solids -- i.e. they have low "ionization yield". A silicon detector was exposed to thermal neutrons over 2.5\,live-days, probing NRs down…
This thesis describes the development of low-energy gap superconducting tunnel junctions (STJs) for use as photon detectors, with as a main goal the improvement of the energy resolution in both the optical and the x-ray energy domain. A new…