Showing papers by "Ken-Ichi Fushimi published in 2007"
TL;DR: In this paper, the giant dipole resonance (GDR) was studied by observing its analog via the $^{4}mathrm{He}$($€7}mathm{Li}$,$€7}\mathm {Be}$ reaction at an incident energy of 455 MeV and at forward scattering angles.
Abstract: We studied the giant dipole resonance (GDR) in $^{4}\mathrm{He}$ by observing its analog via the $^{4}\mathrm{He}$($^{7}\mathrm{Li}$,$^{7}\mathrm{Be}$) reaction at an incident energy of 455 MeV and at forward scattering angles. The spin-nonflip ($\ensuremath{\Delta}S=0$) spectrum was deduced by measuring the 0.43-MeV $^{7}\mathrm{Be}$ \ensuremath{\gamma}-ray in coincidence with the scattered $^{7}\mathrm{Be}$. The total cross section of photodisintegration to the GDR in $^{4}\mathrm{He}$ was derived from the $\ensuremath{\Delta}S=0$ and $\ensuremath{\Delta}L=1$ spectrum. The result agrees well with the previous total photodisintegration data in which the GDR has a pronounced peak at ${E}_{\ensuremath{\gamma}}~27$ MeV.
18 citations
National Institute of Radiological Sciences1, University of Washington2, Osaka University3, Los Alamos National Laboratory4, University of North Carolina at Chapel Hill5, Charles University in Prague6, University of Tokushima7, International Christian University8, Hiroshima University9, Joint Institute for Nuclear Research10, Tohoku University11
TL;DR: In this article, an ensemble of multilayer scintillators is discussed as an option of the high-sensitivity detector MOON (Mo Observatory of Neutrinos) for spectroscopic measurements of neutrinoless double beta decays.
Abstract: An ensemble of multilayer scintillators is discussed as an option of the high-sensitivity detector MOON (Mo Observatory of Neutrinos) for spectroscopic measurements of neutrinoless double beta decays. A prototype detector MOON-1, which consists of 6-layer plastic scintillator plates, was built to study the photon responses of the MOON-type detector. The photon responses, i.e., the number of scintillation photons collected and the energy resolution, which are key elements for high-sensitivity experiments, are found to be 1835 � 30 photoelectrons for 976 keV electrons and � ¼ 2:9 � 0:1% (� E=E ¼ 6:8 � 0:3% in FWHM) at the Q�� � 3 MeV region, respectively. The multilayer plastic scintillator structure with high energy resolution as well as a good signal for the background suppression of � –� rays is crucial for the MOON-type detector to achieve inverted-hierarchy neutrino-mass sensitivity. It will also be useful for medical and other rare-decay experiments as well.
15 citations
TL;DR: In this article, the energy resolution of ultra thin and large area NaI(Tl) scintillator has been developed and the estimated sensitivity for spin-dependent excitation of 127I was discussed.
Abstract: Highly segmented inorganic crystal has been shown to have good performance for dark matter search. The energy resolution of ultra thin and large area NaI(Tl) scintillator has been developed. The estimated sensitivity for spin-dependent excitation of 127I was discussed. The recent status of low background measurement at Oto Cosmo Observatory is reported
2 citations
Journal Article•
TL;DR: In this article, an ensemble of multilayer scintillators is discussed as an option of the high-sensitivity detector MOON (Mo Observatory of Neutrinos) for spectroscopic measurements of neutrinoless double beta decays.
Abstract: An ensemble of multilayer scintillators is discussed as an option of the high-sensitivity detector MOON (Mo Observatory of Neutrinos) for spectroscopic measurements of neutrinoless double beta decays. A prototype detector MOON-1, which consists of 6-layer plastic scintillator plates, was built to study the photon responses of the MOON-type detector. The photon responses, i.e., the number of scintillation photons collected and the energy resolution, which are key elements for high-sensitivity experiments, are found to be 1835 � 30 photoelectrons for 976 keV electrons and � ¼ 2:9 � 0:1% (� E=E ¼ 6:8 � 0:3% in FWHM) at the Q�� � 3 MeV region, respectively. The multilayer plastic scintillator structure with high energy resolution as well as a good signal for the background suppression of � –� rays is crucial for the MOON-type detector to achieve inverted-hierarchy neutrino-mass sensitivity. It will also be useful for medical and other rare-decay experiments as well.