• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • Tagged with
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The search for diffuse interstellar bands in quasar absorption line systems

York, Brian A. 15 August 2008 (has links)
The diffuse interstellar bands (DIBs) probably arise from complex organic molecules whose strength in local galaxies correlates with neutral hydrogen column density, N(H I), and dust reddening, E(B−V). Because Damped Lyman-α systems are known to have high N(H I), and Ca II absorbers in quasar (QSO) spectra are posited to have high N(H I) and reddening, both represent promising sites for the detection of DIBs at cosmological distances. I present the results of a search for diffuse bands in seven DLAs and nine Ca II absorbers. I announce the detection of the first narrow DIBs at z>0 towards one DLA and one Ca II system. I further investigate the relative strengths of the DIBs as well as their correlations with N(H I) and E(B−V). Finally, I discuss the prospects for using DIBs to better understand the properties of quasar absorption systems, and for using DIB searches in absorption systems to better understand the properties of DIBs.
2

The search for diffuse interstellar bands in quasar absorption line systems

York, Brian A. 15 August 2008 (has links)
The diffuse interstellar bands (DIBs) probably arise from complex organic molecules whose strength in local galaxies correlates with neutral hydrogen column density, N(H I), and dust reddening, E(B−V). Because Damped Lyman-α systems are known to have high N(H I), and Ca II absorbers in quasar (QSO) spectra are posited to have high N(H I) and reddening, both represent promising sites for the detection of DIBs at cosmological distances. I present the results of a search for diffuse bands in seven DLAs and nine Ca II absorbers. I announce the detection of the first narrow DIBs at z>0 towards one DLA and one Ca II system. I further investigate the relative strengths of the DIBs as well as their correlations with N(H I) and E(B−V). Finally, I discuss the prospects for using DIBs to better understand the properties of quasar absorption systems, and for using DIB searches in absorption systems to better understand the properties of DIBs.

Page generated in 0.0698 seconds