A comprehensive set of measurements and calculations has been conducted to investigate the accuracy of the Dose Planning Method (DPM) Monte Carlo code for electron beam dose calculations in heterogeneous media. Measurements were made using 10 MeV and 50 MeV minimally scattered, uncollimated electron beams from a racetrack microtron. Source distributions for the Monte Carlo calculations were rec...

Limits at 90% c.l. on the square of the mixing strength |Uτ4| between ντ and a mostly isosinglet heavy neutrino with mass in the range 10–290 MeV/c2 are reported. The results were derived using the negative result of a search for neutral particles decaying into two electrons conducted by the CHARM collaboration in a neutrino beam dump experiment. Upper limits ∼= 10−4 were obtained for neutrino ...

The COMPTEL and EGRET detectors aboard the Compton Gamma-Ray Observatory measured an extragalactic γ-ray background (EGRB) extending from ∼ 1 MeV to ∼ 100 GeV. Calculations performed making reasonable assumptions indicate that blazars can account for the background between ∼ 10 MeV and ∼ 10 GeV. Below 30 MeV, the background flux and spectrum are not very well determined and a dedicated satellit...

New feebly interacting particles would emerge from a supernova core with 100-MeV-range energies and produce $\gamma$-rays by subsequent decays. These contribute to the diffuse cosmic $\gamma$-ray background or have shown up in Solar Maximum Mission (SMM) satellite SN~1987A. However, we show for example of axion-like (ALPs) that, even at distances beyond progenitor star, decay photons may not es...

A pixon-based reconstruction imaging method is applied to CGRO COMPTEL data for Viewing Period 3. The eld-of-view of VP3 contains both the AGN sources 3C273 and 3C279 which are about 10 apart. The pixon technique is able to determine the uxes and locations of a number of discrete sources within close proximity to each other. Fluxes and upper limits have been determined for both sources in the t...

The first neutron spectrometer of ASDEX Upgrade (AUG) was installed in November 2008. It is a compact neutron spectrometer (CNS) based on a BC501A liquid scintillating detector, which can simultaneously measure 2.45-MeV and 14-MeV neutrons emitted from deuterium (D) plasmas and γ radiation. The scintillating detector is coupled to a digital pulse shape discrimination data acquisition (DPSD) sys...

We study the decays of τ → ντPγ (P = π , K) in the light front quark model. We calculate the form factors and use them to evaluate the decay widths. We find that, in the standard model, the decay widths are 1.62 × 10 (3.86 × 10) Γτ−→ντπ− and 1.91 × 10 (5.38 × 10) Γτ−→ντK− with the cuts of Eγ = 50 (400) MeV and t0 = 800 (1200) MeV for τ → ντπγ and τ → ντKγ, respectively. We also show that with i...