eprintid: 14053 rev_number: 21 eprint_status: archive userid: 178 dir: disk0/00/01/40/53 datestamp: 2012-11-28 09:28:47 lastmod: 2012-12-07 13:29:15 status_changed: 2012-11-28 09:28:47 type: doctoralThesis metadata_visibility: show creators_name: Mochol, Iwona title: Nonlinear waves in Poynting-flux dominated outflows subjects: 500 subjects: 520 subjects: 530 divisions: 130001 adv_faculty: af-13 keywords: nonlinear waves, pulsar wind, termination shock, charge starvation, underdense plasma, radiation reaction, blazar jet, magnetosphere cterms_swd: Nichtlineare Welle cterms_swd: Elektromagnetische Welle cterms_swd: Plasmadynamik cterms_swd: Magnetohydrodynamische Welle cterms_swd: Jet cterms_swd: Pulsar cterms_swd: Blazar cterms_swd: Schwarzes Loch cterms_swd: Photon-Drag-Effekt abstract: Rotating, compact objects power some of the most spectacular phenomena in astrophysics, e.g., gamma-ray bursts, active galactic nuclei and pulsar winds. The energy is carried by Poynting flux, and the system is usually modelled using relativistic magnetohydrodynamics (MHD). However, in the relatively low density medium expected around some of these objects, the MHD approximation breaks down, allowing new, large-amplitude waves to propagate. We discuss the role of these waves in two astrophysical contexts: In blazar jets, we show that a magnetic shear, launched together with a plasma from the black hole magnetosphere, begins to accelerate particles at a large distance from its source. The resulting non-thermal emission can, nevertheless, be modulated on very short timescales, which can explain the rapid variability of the TeV gamma-ray flux observed from some blazars. In pulsar winds, we analyze the radial propagation of superluminal modes, including their damping by radiation reaction and by interaction with an external photon field. We discuss their effect on the structure of the pulsar wind termination shock, presenting new solutions in which the nonlinear wave is asymptotically matched to the constant pressure surroundings. The observational implications of these solutions are discussed for both isolated pulsars, and pulsars in binary systems. date: 2012-11-22 id_scheme: DOI id_number: 10.11588/heidok.00014053 ppn_swb: 1651925623 own_urn: urn:nbn:de:bsz:16-heidok-140535 date_accepted: 2012-11-07 advisor: HASH(0x564e1c33d208) language: eng bibsort: MOCHOLIWONNONLINEARW20121122 full_text_status: public citation: Mochol, Iwona (2012) Nonlinear waves in Poynting-flux dominated outflows. [Dissertation] document_url: https://archiv.ub.uni-heidelberg.de/volltextserver/14053/1/thesis.pdf