Conveners
Young Scientists' Session: Cosmic ray acceleration
- Alicja Wierzcholska
We have studied the transport process of galactic cosmic rays invading into the heliosphere using test particle simulations embedded in global MHD simulation of the heliosphere. The heliosphere was reproduced by an MHD simulation under the assumptions that the solar wind is steady with northward solar magnetic polarity and zero tilt angle. Motions of a number of test particles (=galactic...
Search for sources of ultra high energy cosmic rays (UHECRs, $E>10^{18}$ eV) remains one of the main unsolved problems in modern astrophysics. Galactic magnetars are potential candidates for the UHECR accelerators due to their ability to generate relativistic plasma flows and shock waves during magnetar giant flares. Favorable conditions for UHECR acceleration also occur during a Supernova...
Supernova remnants are expected to be the main source of Galactic cosmic rays up to energies of about 3 PeV, provided that they transfer a significant fraction of their kinetic energy to the particles. The bilateral supernova remnant SN 1006 shows bright synchrotron X-ray emission from ultrarelativistic electrons accelerated at the shock front in its northeastern and southwestern limbs. If...
Synchrotron X-ray emission in young supernova remnants (SNRs) is a powerful diagnostic tool to study the population of high energy electrons accelerated at the shock front and the acceleration process. We performed a spatially resolved spectral analysis of NuSTAR and XMM-Newton observations of the young Kepler's SNR, aiming to study in detail its non-thermal emission in hard X-rays. We...
Investigation of astrophysical shocks has a major importance in understanding physics of the cosmic rays acceleration. Electrons to be accelerated at shocks must have an injection energy, which implies that they should undergo some pre-acceleration mechanism. Many numerical studies examined possible injection mechanisms, however most of them considered homogenous upstream medium, which is...
X-ray binaries are systems consisting on a massive star and a compact object. If the compact object is a pulsar, both the star and the pulsar will have their own winds. When both winds clash, they produce a contact discontinuity which creates shocked flows that go away from the binary and are affected by the orbital motion of the system. These flows are a plasma made by charged particles and...
Relativistic shocks possess a central role in energetic astrophysical phenomena, with gamma-ray bursts (GRBs) being a prominent example. This has led to the extensive investigation of the properties of shocks propagating in both non-magnetized and magnetized fluids characterized by infinite electrical conductivity. The derivation of the jump conditions for a relativistic shock propagating in a...
Astrophysical jets are considered among the most stable structures throughout the cosmos, as they are able to propagate to distances many times their initial radii. In this context we conduct a linear stability analysis on astrophysical outflows, for which the dynamics are described by the relativistic magnetohydrodynamics. A new peculiar solution emerged, having instabilities' growth...
