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Continuum fitting hst qso spectra
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Tytler, David |
| Copyright Year | 2002 |
| Description | The Principal Component Analysis (PCA) method which we are using to fit and describe QSO spectra relies upon the fact that QSO continuum are generally very smooth and simple except for emission and absorption lines. To see this we need high signal-to-noise (S/N) spectra of QSOs at low redshift which have relatively few absorption lines in the Lyman-a forest. We need a large number of such spectra to use as the basis set for the PCA analysis which will find the set of principal component spectra which describe the QSO family as a whole. We have found that too few HST spectra have the required S/N and hence we need to supplement them with ground based spectra of QSOs at higher redshift. We have many such spectra and we have been working to make them suitable for this analysis. We have concentrated on this topic since 12/15/01. |
| File Size | 211794 |
| Page Count | 3 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20020039047 |
| Archival Resource Key | ark:/13960/t4mm18q8n |
| Language | English |
| Publisher Date | 2002-03-01 |
| Access Restriction | Open |
| Subject Keyword | Astrophysics Quasars Red Shift Fitting Signal To Noise Ratios Spectrum Analysis Continuums Line Spectra Continuous Spectra Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
