Energy Spectra

The dramatic increase in the number of known gamma-ray pulsars since the launch of the Fermi Gamma-ray Space Telescope (formerly GLAST) offers the first opportunity to study a sizable population of these high-energy objects. This catalog summarizes 46 high-confidence pulsed detections using the first six months of data taken by the Large Area Telescope (LAT), Fermi's main instrument. Sixteen previously unknown pulsars were discovered by searching for pulsed signals at the positions of bright gamma- ...

We explore the possibility to improve the performance of 0.5 cm thick cadmium zinc telluride (CZT) detectors with the help of steering grids on the anode side of the detectors. Steering grids can improve the energy resolution of CZT detectors by enhancing the small pixel effect; furthermore, they can increase their detection efficiency by steering electrons to the anode pixels which otherwise would drift to the area between pixels. Previously, the benefit of steering grids had been compromised by additional noise associated with ...

This proposal describes an experimental search for sterile neutrinos beyond the Standard Model with a new CERN-SPS neutrino beam. The experiment is based on two identical LAr-TPC's followed by magnetized spectrometers, observing the electron and muon neutrino events at 1600 and 300 m from the proton target. This project will exploit the ICARUS T600, moved from LNGS to the CERN "Far" position. An additional 1/4 of the T600 detector will be constructed and located in the "Near" position. Two spectrometers will be placed downstream of the two LAr-TPC detectors to greatly complement the physics capabilities. Spectrometers will exploit a classical dipole magnetic field with iron slabs, and a new concept air-magnet, to perform charge identification and muon momentum measurements in a wide energy range over a large transverse area. In the two positions, the radial and energy spectra of the nu_e beam are practically identical. Comparing the two detectors, in absence ...

We describe the experimental arrangement to study the energy distribution of backscattered electrons. Primary electrons come from a 15-MeV linear accelerator. The scattering chamber permits a continuous change of the angular position of the observation port by keeping the vacuum inside together with an analyzer magnet. A scintillation detector catches analyzed electrons, sending the dc output to a recorder. The energy resolution of the total arrangement attainable is about 3%.

... Ley-Koo et al ... In this work using three-band Kane's model, including the conduction band, light spin-orbital hole bands and the spectrum of carriers of quantum wire is calculated for two cases: (1) in the presence of Aharonov–Bohm flux Φ created by a solenoid inserted inside the ...

The dramatic increase in the number of known gamma-ray pulsars since the launch of the Fermi Gamma-ray Space Telescope (formerly GLAST) offers the first opportunity to study a sizable population of these high-energy objects. This catalog summarizes 46 high-confidence pulsed detections using the first six months of data taken by the Large Area Telescope (LAT), Fermi's main instrument. Sixteen previously unknown pulsars were discovered by searching for pulsed signals at the positions of bright gamma- ...

The power spectrum is measured in direct numerical simulations of the two-dimensional Navier-Stokes equation and other two-dimensional flows with white-in-time forcing at large scales. For the Navier-Stokes equation the energy spectrum in the inertial range approaches k(-3) with increasing Reynolds number, with possible logarithmic corrections. A family of two-dimensional flows, including the surface quasigeostrophic equation, allows us to vary the locality of the "enstrophy" transfer, where enstrophy is the mean square of the convected quantity. Dimensional analysis based on the enstrophy dissipation correctly predicts the energy spectrum, whenever the enstrophy transfer can be assumed to be spectrally local. Otherwise, the enstrophy spectrum is steeper than would be expected on the basis of local transfer. In this case the data suggest a k(-1) passive scalar spectrum.

We study gravitational waves from a particle moving around a system of a point mass with a disk in Newtonian gravitational theory. A particle motion in this system can be chaotic when the gravitational contribution from a surface density of a disk is comparable with that from a point mass. In such an orbit, we sometimes find that there appears a phase of the orbit in which particle motion becomes to be nearly regular (the so-called ``stagnant motion'') for a finite time interval between more strongly chaotic phases. To study how these different chaotic behaviours affect on observation of gravitational waves, we investigate a correlation of the particle motion and the waves. We find that such a difference in chaotic motions reflects on the wave forms and energy spectra. The character of the waves in the stagnant motion is quite different from that either in a regular motion or in a more strongly chaotic motion. This suggests that we may make a distinction between different ch...

Abstract—FLUKA Monte Carlo simulations have been per-formed to identify particle energy spectra and fluences relevant for evaluating the risk of single event effects in electronics installed in critical LHC underground areas. Since these simulations are associated with significant ...

In order to gain some insight on the electronic relaxation mechanisms occuring in diamond under high intensity laser excitation and/or VUV excitation, we studied experimentally the pulsed conductivity induced by femtosecond VUV pulses, as well as the energy spectra of the photoelectrons released by the same irradiation. The source of irradiation consists in highly coherent VUV pulses obtained through high