18 research outputs found
Multi-layer scintillation detector for the MOON double beta decay experiment: Scintillation photon responses studied by a prototype detector MOON-1
An ensemble of multi-layer scintillators is discussed as an option of the
high-sensitivity detector Mo Observatory Of Neutrinos (MOON) for spectroscopic
measurements of neutrino-less double beta decays. A prototype detector MOON-1,
which consists of 6 layer plastic-scintillator plates, was built to study the
sensitivity of the MOON-type detector. The scintillation photon collection and
the energy resolution, which are key elements for the high-sensitivity
experiments, are found to be 1835+/-30 photo-electrons for 976 keV electrons
and sigma = 2.9+/-0.1% (dE/E = 6.8+/-0.3 % in FWHM) at the Qbb ~ 3 MeV region,
respectively. The multi-layer plastic-scintillator structure with good energy
resolution as well as good background suppression of beta-gamma rays is crucial
for the MOON-type detector to achieve the inverted hierarchy neutrino mass
sensitivity.Comment: 8 pages, 16 figures, submitted to Nucl.Instrum.Met
Photoemission Spectroscopy and Atomic Force Microscopy Investigation of Vapor Phase Co-Deposited Silver/Poly(3-hexylthiophene) Composites
Nanocomposite matrices of silver/poly(3-hexylthiophene) (P3HT) were prepared
in ultrahigh vacuum through vapor-phase co-deposition. Change in
microstructure, chemical nature and electronic properties with increasing
filler (Ag) content were investigated using in-situ XPS and UPS, and ambient
AFM. At least two chemical binding states occur between Ag nanoparticles and
sulfur in P3HT at the immediate contact layer but no evidence of interaction
between Ag and carbon (in P3HT) was found. AFM images reveal a change in Ag
nanoparticles size with concentration which modifies the microstructure and the
average roughness of the surface. Under co-deposition, P3HT largely retains its
conjugated structures, which is evidenced by the similar XPS and UPS spectra to
those of P3HT films deposited on other substrates. We demonstrate here that the
magnitude of the barrier height for hole injection and the position of the
highest occupied band edge (HOB) with respect to the Fermi level of Ag can be
controlled and changed by adjusting the metal (Ag) content in the composite.
Furthermore, UPS reveals distinct features related to the C 2p (Sigma states)
in the 5-12 eV regions, indicating the presence of ordered P3HT which is
different from solution processed films.Comment: Scudier and Wei provided equal contributio
Piezoelectric behavior of wood under combined compression and vibration stresses II: Effect of the deformation of cross-sectional wall of tracheids on changes in piezoelectric voltage in linear-elastic region
Dual inhibition of JAK1/2 kinases and BCL2: a promising therapeutic strategy for acute myeloid leukemia
Impact of frontal white matter hyperintensity on instrumental activities of daily living in elderly women with Alzheimer disease and amnestic mild cognitive impairment
MOON (Mo Observatory Of Neutrinos) for double beta decay
The MOON (Molybdenum Observatory Of Neutrinos) project aims at studies of double beta decays with a high sensitivity of < mν >∼0.03 eV and real-time studies of low-energy solar neutrinos. Two β rays from 100 Mo are measured in coincidence for the 0νββ studies. The inverse β rays from solar neutrino captures of 100 Mo are measured in delayed coincidence with the following β decay of 100 Tc. Measurements with good energy resolution and good position resolution enable one to select true signals. A prototype MOON detector (MOON 1) is now under development. The present report describes briefly the outline of the MOON project and the status of MOON 1