Related papers: Precision imaging of 4.4 MeV gamma rays using a 3-…
Classical novae produce radioactive nuclei which are emitters of gamma-rays in the MeV range. Some examples are the lines at 478 and 1275 keV (from 7Be and 22Na) and the positron-electron annihilation emission (511 keV line and a continuum…
The GAMMA-400 gamma-ray telescope with excellent angular and energy resolutions is designed to search for signatures of dark matter in the fluxes of gamma-ray emission and electrons + positrons. Precision investigations of gamma-ray…
Due to their very fast signal rise time in the order of 1 ns, Silicon-Photomultipliers have become of increasing interest for many experiments that require very good timing resolution. With the prospect of an application in medical imaging…
The emission mechanism of the gamma-ray bursts (GRBs) is still a matter of debates. The standard synchrotron energy spectrum of cooling electrons F_E ~ E^{-1/2} is much too soft to account for the majority of the observed spectral slopes.…
The Mega electron volt (MeV) gamma-ray observation is a promising diagnostic tool for observing the universe. However, the sensitivity of MeV gamma-ray telescopes is limited due to peculiar backgrounds, restricting the application of MeV…
A novel radiation detector based on an artificial single crystal diamond was used to characterize in detail the energy distribution of neutron reference fields at the Physikalisch-Technische Bundesanstalt (PTB) and their contamination with…
While the scientific potential of high-energy X-ray and gamma-ray polarimetry has long been recognized, measuring the polarization of high-energy photons is challenging. To date, there has been very few significant detections from an…
The differential spectrum of TeV gamma rays between 1.5 TeV and 20 TeV from the north-east rim of SN1006 was obtained from the data observed in 1996 and 1997 using the 3.8m CANGAROO \v{C}erenkov telescope. This spectrum matches the model…
We describe a very compact (0.9 m high, 0.4 m diameter, 40 kg) battery operable neutron scatter camera designed for field deployment. Unlike most other systems, the configuration of the sixteen liquid-scintillator detection cells are…
We discuss the possibility of observing distant accelerators of ultra high energy cosmic rays in synchrotron gamma rays. Protons propagating away from their acceleration sites produce extremely energetic electrons during photo-pion…
All-optical Compton sources are innovative, compact devices to produce high energy femtosecond X-rays. Here we present results on a single-pulse scheme that uses a plasma mirror to reflect the drive beam of a laser plasma accelerator and to…
Protons can be plausibly accelerated to $\sim 10^{18}$-$10^{19}$ eV in strong accretion shocks surrounding massive clusters of galaxies. Such protons efficiently produce very high energy pairs through interactions with the CMB, which then…
The pp -> pp gamma reaction has been studied at a beam energy of 310 MeV by detecting both final protons at the PROMICE-WASA facility and identifying the photon through the resulting missing-mass peak. The photon angular distribution in the…
Surgical tumor resection aims to remove all cancer cells in the tumor margin and at centimeter-scale depths below the tissue surface. During surgery, microscopic clusters of disease are intraoperatively difficult to visualize and are often…
The preliminary design of the new space gamma-ray telescope GAMMA-400 for the energy range 100 MeV - 3 TeV is presented. The angular resolution of the instrument, 1-2{\deg} at E{\gamma} ~100 MeV and ~0.01^{\circ} at E{\gamma} > 100 GeV, its…
The interaction of radiation with liquid xenon, inducing both scintillation and ionization signals, is of particular interest for Compton-sequences reconstruction. We report on the development and recent results of a liquid-xenon…
The total cross section for Compton scattering off atomic electrons, $\gamma+e\rightarrow\gamma'+e'$, was measured using photons with energies between 6.5 and 11.1 GeV incident on a $^9$Be target as part of the PrimEx-eta experiment in Hall…
We have obtained a firm detection of Cyg X-1 during its hard and intermediate spectral states in the energy range of 40 MeV--60 GeV based on observations by the Fermi Large Area Telescope, confirming the independent results at $\geq$60MeV…
The focusing strength of plasma lenses used with high energy electron or positron beams can give rise to synchrotron radiation with critical energies in the MeV range. A method is described for measuring the characteristic energy of this…
We convert a GeV laser-plasma electron accelerator into a compact femtosecond-pulsed $\gamma$-ray source by inserting a $100 \mu$m-thick glass plate $\sim3$ cm after the accelerator exit. With near-unity reliability, and requiring only…