Related papers: Annihilation-Gamma-based Diagnostic Techniques for…
In a new divertor simulator, an ultra-cold (Te<1 eV) high density recombining magnetized laboratory plasma is studied using probes, spectroscopic measurements, and ultra-fast imaging of spontaneous emission. The Mistral-B device consists in…
We study direct and indirect detection possibilities of neutralino dark matter produced non-thermally by e.g. the decay of long-lived particles, as is easily implemented in the case of anomaly or mirage mediation models. In this scenario,…
Plasma-based optics have emerged as a powerful platform for manipulating and amplifying ultra-intense laser pulses. However, the inherently nonlinear and dynamic nature of plasma leads to significant spatial, spectral, and temporal…
We present a spectral analysis of the e+e- annihilation emission from the Galactic Centre region based on the first year of measurements made with the spectrometer SPI of the INTEGRAL mission. We have found that the annihilation spectrum…
Intense radiation field can modify plasma properties, the corresponding refractive index, and lead to such nonlinear propagation effects as self-focusing. We estimate the corresponding effects in pair plasma, both in unmagnetized and…
Although the annihilation of positrons towards the Galactic centre was established more than 50 years ago through the detection of a 511 keV $\gamma$-ray line, the origin of the positrons remains unknown. The $\gamma$-ray line should be…
The main idea and procedure are presented for a new synthetical method on constraining 3-D structure of emission regions of pulsars. With this method the emission regions can be synthetically constrained by fitting multi-wavelength…
A simultaneous analysis of high-resolution directional Compton profiles and two-dimensional angular correlation of positron annihilation experimental data has been performed by studying both a directional anisotropy of measured spectra and…
The excess in the positron fraction reported by the PAMELA collaboration has been interpreted as due to annihilation or decay of dark matter in the Galaxy. More prosaically, it has been ascribed to direct production of positrons by nearby…
We simulate magnetic reconnection in electron-positron (pair) plasma using a collisionless two-fluid model with isotropic pressure. In this model the resistive, Hall, and electrokinetic pressure terms are absent from the curl of Ohm's law,…
We report a technique of proton deflectometry which uses a grid and an in situ reference x-ray grid image for precise measurements of magnetic fields in high-energy density plasmas. A D$^3$He fusion implosion provides a bright point-source…
Interaction of an ultrastrong short laser pulse with non-prepolarized near-critical density plasma is investigated in an ultrarelativistic regime, with an emphasis on the radiative spin polarization of ejected electrons. Our…
Dark matter annihilation in Galactic substructure will produce diffuse gamma-ray emission of remarkably constant intensity across the sky, making it difficult to disentangle this Galactic dark matter signal from the extragalactic gamma-ray…
This paper uses extended-magnetohydrodynamics (MHD) simulations to explore an extreme magnetized plasma regime realisable by cylindrical implosions on the OMEGA laser facility. This regime is characterized by highly compressed magnetic…
Linearly polarized emission is described, in general, in terms of the Stokes parameters $Q$ and $U$, from which the polarization intensity and polarization angle can be determined. Although the polarization intensity and polarization angle…
Scattering measurements with incident linearly polarized $\gamma$ rays provide information on spins, parities, and $\gamma$-ray multipolarity mixing coefficients, and, therefore, on the nuclear matrix elements involved in the transitions.…
Spatial distributions of electrons ionized and scattered from ultra-low pressure gases are proposed and experimentally demonstrated as a method to directly measure the intensity of an ultra-high intensity laser pulse. Analytic models…
Motivated by the anomalous positron flux recently reported by the PAMELA collaboration, we study the cosmic-ray positron produced by the pair annihilation and the decay of superparticle dark matter. We calculate the cosmic-ray positron flux…
The emission from the relativistically hot plasmas of high-energy astrophysical synchrotron sources, pulsar wind nebulae (PWNe) in particular, depends on the level of magnetic fluctuations. Recent observations by the X-ray polarimeter IXPE…
We use holographic methods to show that photons emitted by a strongly coupled plasma subject to a magnetic field are linearly polarized regardless of their four-momentum, except when they propagate along the field direction. The…