Observations of high mass star formation using BLAST and Herschel

Harry, Sarah 2011. Observations of high mass star formation using BLAST and Herschel. PhD Thesis, Cardiff University. Item availability restricted.

Preview	PDF - Accepted Post-Print Version Available under License Creative Commons Attribution Non-commercial No Derivatives. Download (9MB) | Preview
	PDF - Supplemental Material Restricted to Repository staff only Download (3MB)

Abstract

In this thesis, I present BLAST observations of the Carina Nebula and Herschel observations of NGC7538. I use the source extracting routine CSAR to identify 172 source in Carina and 94 sources in NGC7538. I fit SEDs to all the sources and calculate their mass, luminosity, temperature and radius. For the Carina Nebula I find a mass range of 20 – 10 4M¯, a luminosity range of 10 2 – 10 5 L¯, a temperature range of 16 – 28 K, and source radii range of 0.3 – 3.2 pc. For NGC7538 I find a mass range of 5 – 10 3M¯, a luminosity range of 5 – 10 3 L¯, a temperature range of 10 – 40K and a source radii range of 0.1 – 2 pc. I cross - check the source extraction method using the routine, GETSOURCES. This algorithm found a total of 621 sources in NGC7538. The GETSOURCES catalogue is filtered to removed sources which are present in two or less wavelengths. This filtered catalogue then has a good correlation with the CSAR catalogue. Using both catalogues a robust source list of 75 sources is created from sources found by both routines. I plot the mass against radius for both the Carin Nebula and NGC7538. For Carina the data are best fitted by M / R1.8 which is comparable to the Larson relation of M / R2. In NGC7538 I find no relation. I find no temperature dependence in the Carina Nebula with any other source property but find a weak relation between temperature and luminosity in NGC7538. Both regions show a relation of L / M. I find a relation between radius and Luminosity per unit volume where smaller sources have a higher luminosity per unit volume and the larger sources have a lower value. I find sources with a luminosity per unit volume less then 1L¯pc−3 tend to lie in the less dense regions of the nebulae and sources with a luminosity per unit volume greater then 3.5L¯pc−3 lie in the denser regions where the more evolved sources tend to be. This could show that the luminosity per unit volume can trace the evolutionary status of sources in a region.

Item Type:	Thesis (PhD)
Status:	Unpublished
Schools:	Physics and Astronomy
Subjects:	Q Science > QB Astronomy
Uncontrolled Keywords:	Star formation; Dust; Infrared; ISM; Clouds
Funders:	STFC
Date of First Compliant Deposit:	30 March 2016
Last Modified:	19 Mar 2016 22:23
URI:	https://orca.cardiff.ac.uk/id/eprint/14483

Actions (repository staff only)

Edit Item