Measurements of neutron total and capture cross sections of 139^{139}La and evaluation of resonance parameters

Neutron total and capture cross sections of Lanthanum(La)-139 were measured at the Accurate Ne-utron-Nucleus Reaction measurement Instrument (ANNRI) of the Materials and Life Science Experimental Facility (MLF) in the Japan Proton Accelerator Research Complex (J-PARC). The total cross section was largely different from that in evaluated libraries, such as JENDL-5, in the energy range from 80 to 900~eV. Resonance parameters for four resonances including one negative resonance were obtained using a resonance analysis code, REFIT. The resonance analysis revealed discrepancies in several resonance parameters with the evaluated libraries. Furthermore, the information about the scattering radius was also extracted from the results of the total cross section. The obtained scattering radius was larger than that recorded in the evaluated libraries.Comment: 12 pages, 16 figure

Late airway obstruction and neutrophil infiltration in sensitized mice after antigen provocation were suppressed by selective and non-selective phosphodiesterase inhibitors

Suppression of antigen-induced late airway obstruction associated with neutrophilic inflammation by selective and non-selective phosphodiesterase (PDE) inhibitors was investigated in mice. Respiratory resistance (Rrs) increased in sensitized BDF1 mice 4-6 h after antigen provocation, whereas no obvious immediate reaction was observed. This reaction was associated with marked airway neutrophilia without significant infiltration of eosinophils. A selective PDE IV inhibitor, T-440 (10-30 mg/kg), and a non-selective PDE inhibitor, theophylline (10 mg/kg), significantly inhibited airway obstruction and neutrophilia when administered orally. An anti-allergic drug, ketotifen (1 mg/kg), caused slight inhibition of airway obstruction, whereas it did not affect airway neutrophilia. These results suggest that neutrophilic inflammation plays a role in the airway obstructive reaction and that PDE has a regulatory role in obstructive airway disease associated with airway inflammation

Acoustic Response of Piezoelectric Lead-Zirconate-Titanate to a 400 MeV/n Xenon Beam

Characteristics of lead-zirconate-titanate (PZT) elements were studied by directly irradiating them with a 400 MeV/n Xe beam. The elements were sensitive to 10**4 Xe ions and their output amplitudes were proportional to the beam intensity. An ensemble of those output amplitudes displayed a Bragg-curve-like response towards the range of 400 MeV/n Xe ion. We disuss the potential of PZT elements as a radiation detector and their application to high-intensity and high-energy detectors

Energy spectra of prompt gamma rays from Al and Fe thick targets irradiated by helium and proton beams: Concerning planetary gamma-ray spectroscopy

Bombardment experiments with thick targets made of each of Al and Fe were performed using 230 MeV/nucleon helium and 210 MeV proton beams. The energies and intensities of prompt gamma rays emitted by inelastic nuclear scattering of energetic neutrons were measured by a high-purity Ge detector. This work presents the first experimental results concerning the emission of prompt gamma rays from thick targets anticipated by helium component in galactic cosmic rays, since no foregoing work related to this one has been done. It is concluded that helium has the capability of prompt gamma ray line emission through the inelastic nuclear reaction of neutrons with target material by a factor of 3.5 on average in comparison with proton. As regards the lunar and planetary nuclear spectroscopy, a consideration is given on the role of helium particles to the total production of gamma rays emitted from a planetary surface

Response from piezoelectric elements appearing immediately after collisions with silver particles

Ferroelectric lead zirconate titanate(PZT) elements were studied by directly bombarding them with hypervelocity silver particles. The mass and velocity of these hypervelocity silver particles ranged from 1to80pg and 2to6km/s, respectively. This report examines the pulsed signals observed immediately after collision. The first cycle of the pulse is discussed because the information on impact is presumably recorded on the wave form. The experimental data were analyzed using the wave form that was generated immediately after collision. Consequently, the following conclusions were made: (1) the sensitivity of the element is independent of the thickness of element, (2) the pulse height is proportional to the particle momentum over the measured range, and (3) the wave form is not explicitly related to the velocity of the particles at the time of collision. The potential of a single PZT element acts as a real-time detector for hypervelocity microparticles is discussed