Direkt zum Inhalt
  1. Publizieren |
  2. Suche |
  3. Browsen |
  4. Neuzugänge rss |
  5. Open Access |
  6. Rechtsfragen |
  7. EnglishCookie löschen - von nun an wird die Spracheinstellung Ihres Browsers verwendet.

An Integral View of Shocks

Knežević, Sladjana

[thumbnail of PhDThesis_SladjanaKnezevic.pdf]
Vorschau
PDF, Englisch
Download (14MB) | Nutzungsbedingungen

Zitieren von Dokumenten: Bitte verwenden Sie für Zitate nicht die URL in der Adresszeile Ihres Webbrowsers, sondern entweder die angegebene DOI, URN oder die persistente URL, deren langfristige Verfügbarkeit wir garantieren. [mehr ...]

Abstract

The subject of this thesis are Balmer-dominated shocks around (super)novae. These are characterized by strong hydrogen emission lines with a narrow (~10km/s) and a broad (~1000km/s) component. Studying shock physics is important for improving distance estimates to (super)novae, for understanding their evolution and impact on the interstellar medium, and for obtaining insights into the cosmic ray origin in the remnants of supernovae. Two historical supernova remnants, SN 1006 and SN 1572 (Tycho), are investigated using high-resolution spectrophotometric imaging. Analyzing the widths and intensities of the narrow and broad H�alpha-line components, evidence of suprathermal protons – seeds of high-energy cosmic ray protons – is found in SN 1006. Those cause an underestimation of the estimated shock velocity and, hence, the distance to the remnant. In SN 1572, our observations indicate an additional intermediate-width (~100km/s) component, implying the presence of a broad-neutral precursor. Moreover, the narrow component is typically broader than the maximally expected 20 km/s and is sometimes even doublepeaked, which might be due to a cosmic-ray precursor or the shock geometry. The last part of the thesis outlines how high-spatial resolution spectrographs can be used to study and better understand outflow mechanisms of novae, here of a classical nova FH Ser. Further development of shock models that include non-thermal physics, and their application to the data presented in this thesis, are expected to provide important constraints on hadronic cosmic ray properties.

Dokumententyp: Dissertation
Erstgutachter: van de Ven, Dr. Glenn
Tag der Prüfung: 17 Oktober 2014
Erstellungsdatum: 30 Okt. 2014 10:38
Erscheinungsjahr: 2014
Institute/Einrichtungen: Fakultät für Physik und Astronomie > Dekanat der Fakultät für Physik und Astronomie
DDC-Sachgruppe: 520 Astronomie
Leitlinien | Häufige Fragen | Kontakt | Impressum |
OA-LogoDINI-Zertifikat 2013Logo der Open-Archives-Initiative