2011suppermaphd.pdf (6.21 MB)
Investigating the Soft X-ray Background of the Milky Way
thesis
posted on 2011-08-25, 11:27 authored by Michelle Abbie SupperThis thesis uses the data from twenty ROSAT and XMM observations to investigate the structures that generate the soft X-ray background of the Milky Way. Ten of these observations lie in the direction of the Loop 1 Superbubble, specifically, within the North Polar Spur, the Northern Bulge, and immediately south of the Galactic Plane. The others are located in the Anti-centre direction, where the X-ray background is less complex.
Using a novel processing technique, point sources and enhancements were successively removed from the observations until only the Diffuse X-ray Background (DXRB) re¬mained. By modelling the spectra of this clean data, and separately analysing the 0 and 0 viii emission lines, the various structures in the DXRB were identified, and their properties determined.
The resulting models strongly indicate the existence of three previously unidentified components: a 14 pc thick, 0.1 keV shell surrounding Loop I, an inhomogeneous 0.25 keV Galactic Halo, and a non-thermal component present in the Galactic Centre direction. In contrast with previous work, no evidence was found for a cool Galactic Halo. The centre of Loop I was placed 290 pc away, 80 pc farther than previously believed. Additionally, an ongoing interaction was discovered between the Local Hot Bubble and Loop I.
History
Supervisor(s)
Raine, DerekDate of award
2011-07-01Awarding institution
University of LeicesterQualification level
- Doctoral
Qualification name
- PhD