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The dynamics, energetics and evolution of pulsar wind nebulae (PWNe) and supernova remnants (SNRs), are strongly affected by their magnetic field strength and distribution. They are usually strong, extended, sources of non-thermal X-ray radiation, producing intrinsically polarised radiation. The energetic wind around pulsars produces a highly-magnetised, structured flow, often displaying a jet and a torus and different features (i.e. wisps, knots). This magnetic-dominant wind evolves as it moves away from the pulsar magnetosphere to the surrounding large-scale nebula, becoming kinetic-dominant. Basic aspects such how this conversion is produced, or how the jets and torus are formed, as well as the level of turbulence in the nebula are still unknown. Likewise, the processes ruling the acceleration of particles in shell-like SNRs up to 1015 eV, including the amplification of the magnetic field, are not clear yet. Imaging polarimetry in this regard is crucial to localise the regions of shock acceleration and to measure the strength and the orientation of the magnetic field at these emission sites. X-ray polarimetry with the X-ray Imaging Polarimetry Explorer (XIPE) will allow the understanding of the magnetic field structure and intensity on different regions in SNRs and PWNe, helping to unveil long-standing questions such as i.e. acceleration of cosmic rays in SNRs or magnetic-to-kinetic energy transfer. SNRs and PWNe also represent the largest population of Galactic very-high energy gamma-ray sources, therefore the study of their magnetic distribution with XIPE will provide fundamental ingredients on the investigation of those sources at very high energies. We will discuss the physics case related to SNRs and PWNe and the expectations of the XIPE observations of some of the most prominent SNRs and PWNe. [ABSTRACT FROM AUTHOR]

The diffuse γ-ray emission produced by hadronic interaction of cosmic rays (CR) with the interstellar medium (ISM) during their propagation through the Galaxy, reveals important information on the diffusion properties of the ISM as well as on the global distribution of CR sources. In this work we estimate the contribution of γ-ray emission due to the CR self-confined near their acceleration sites. In fact, when CR leave their parent source, they self-generate magnetic turbulence through streaming instability. Such turbulence, in turn, enhances the scattering rate of CRs, increasing their residence time in the region. The streaming instability can be effective within a distance of the order of the coherence scale, Lc, of the background magnetic field from the source, where the density of CRs produced by the source is expected to be larger than the average Galactic value. Nevertheless, the effectiveness strongly dependents on the density of neutral hydrogen, because the ion-neutral friction can suppress the wave amplification. A direct consequence of the self-confinement of CRs is the formation of an extend halo of γ-ray emission of size ~ Lc around each source. The emission from a single halo is too faint to be detected but the sum of these halos over the whole CR source population can be a non negligible contribution to the diffuse gamma-ray emissivity from the Galactic disc. Therefore, we want to compare the predicted emission from the total halo's population with the diffuse Galactic emission measured by the Fermi-LAT telescope. To do this calculation, we assume that CR sources are Supernova Remnants (SNRs) exploding either in a fully ionized or in a partially ionized ISM. While in the former case the halos emission almost saturate the observed Galactic emission, in the latter, due to the ion-neutral friction, the gamma-ray emission is strongly reduced, being non negligible only for energies of γ-rays Eγ ~ 100 GeV. [ABSTRACT FROM AUTHOR]

The ELI-Beamlines facility in the Czech Republic will offer to users versatile radiation sources in an unprecedented energy range. Laser-driven proton beams are expected to range between 50 MeV and 3 GeV. The number of particles delivered per laser shot is estimated to be 1010-1012. Starting from analytical calculations, as well as from dedicated simulations, the main proton fields produced in the laser-matter interaction have been described and used to characterize the "source terms" in full simulations with the Monte Carlo code FLUKA in order to assess a proper shielding. We present the results of this study and the proposed solutions together with a cross-check analysis performed with the Monte Carlo code GEANT4. [ABSTRACT FROM AUTHOR]