High Velocity Outflows in Quasars

Permanent Link:

https://ufdc.ufl.edu/UFE0022674/00001

Material Information

Title:

High Velocity Outflows in Quasars

Creator:

Rodriguez, Paola

Place of Publication:

[Gainesville, Fla.]

Publisher:

University of Florida

Publication Date:

2009

Language:

english

Physical Description:

1 online resource (141 p.)

Thesis/Dissertation Information

Degree:

Doctorate ( Ph.D.)

Degree Grantor:

University of Florida

Degree Disciplines:

Astronomy

Committee Chair:

Hamann, Fredrick

Committee Members:

Tan, Jonathan
Sarajedini, Vicki L.
Eikenberry, Stephen S.
Fry, James N.
Crenshaw, Daniel

Graduation Date:

5/2/2009

Subjects

Subjects / Keywords:

Absorption spectra ( jstor )
Emission spectra ( jstor )
Ionization ( jstor )
Ions ( jstor )
Line spectra ( jstor )
Property lines ( jstor )
Quasars ( jstor )
Red shift ( jstor )
Velocity ( jstor )
Wavelengths ( jstor )
Astronomy -- Dissertations, Academic -- UF
high, outflows, quasars, variability

Genre:

Electronic Thesis or Dissertation
born-digital ( sobekcm )
Astronomy thesis, Ph.D.

Notes

Abstract:

Outflows are a fundamental part of quasars: they bring first-hand physical information about the quasar environments, they are common (and maybe ubiquitous) and they might be key to connecting the AGN with their host galaxies. Nonetheless, many aspects of these outflows are poorly understood. For example, we still do not understand the acceleration mechanisms that drive the flows off of the accretion disks to speeds reaching 0.1c -- 0.2c. I present new measurements and analyses of one of the most extreme cases: the high velocity outflow (v ~ 51000 km/s) observed in the spectra of PG0935+417 (z sub (em) ~ 1.97). We use a combination of ground-based (Lick observatory and Sloan Digital Sky Survey - SDSS) and space-based (Hubble Space Telescope) spectra to measure the absorption in CIV lambda1549 and, for the first time, OVI lambda1034 and NV lambda1240 in the same outflow. The absence of lower ionization lines indicates that the flow is highly ionized with an ionization parameter of log U ~ -1.1. The resolved OVI indicates that the lines are moderately saturated with the absorber covering just ~80\% of the background emission source. We estimate the total column density to be N sub H > ~ 3.0 x 10^{19} cm^{-2}, which is small enough to be compatible with radiation pressure mechanisms accelerating this outflow. I also contribute to the study of outflows by surveying a realm of parameter space that has been sparsely studied before: mini-broad absorption lines (mini-BALs) and high velocities (v > ~ 10000 km/s). My goals are to 1) quantitatively define the range of outflow lines in quasar spectra, 2) examine their detection frequencies and distributions in velocity, strength and FWHM, 3) look for relationships between the various absorption line types and basic quasar properties, and 4) identify individual outflow lines candidates for follow-up studies. To do so, I compile a comprehensive catalog of CIV absorption lines in the ~2200 brightest SDSS quasars at 1.8 < = z < = 3.5, and select those with FWHM > 700 km s$^{-1}$ to be unlikely due to intervening material. I obtain a fraction of quasars with mini-BALs of 11.4%+-0.9%. Although the mini-BAL phenomenon is strongly related to the more previously studied Broad Absorption Lines (BALs) present in BALQSOs, I still find mini-BALs in 5.1%+-0.7% of non-BALQSOs. I find no correlation between the presence of associated absorbers or radio loudness and the occurance of mini-BALs. By adding results from other outflow studies, I estimate a total percentage of quasars with outflows to be > ~ 41 to 77%. Finally, in order to characterize better the structural and physical properties of these outflows, I carried out a monitoring program over a range of Delta t = 0.9 -- 3.3 years in the quasar rest frame by using facilities at the Kitt Peak National Observatory and MDM Observatory. By comparing our new spectra with archival spectra (SDSS), I find that ~50% of quasars with mini-BAL and BALs at high velocity varied between just two observations. I find that variability sometimes occurs in complex ways; however, all the variable lines vary in intensity and not in velocity. Thus I find no evidence for acceleration/deceleration in the outflow. I also do not find any correlations between the variability and Rest Equivalent Width (REW), Full Width Half Minumum (FWHM) or depth of the absorption feature, except for the fact that none of the narrower systems varied. A significant fraction of the non-variable narrower systems are probably unrelated to quasar outflows. ( en )

General Note:

In the series University of Florida Digital Collections.

General Note:

Includes vita.

Bibliography:

Includes bibliographical references.

Source of Description:

Description based on online resource; title from PDF title page.

Source of Description:

This bibliographic record is available under the Creative Commons CC0 public domain dedication. The University of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.

Thesis:

Thesis (Ph.D.)--University of Florida, 2009.

Local:

Adviser: Hamann, Fredrick.

Electronic Access:

RESTRICTED TO UF STUDENTS, STAFF, FACULTY, AND ON-CAMPUS USE UNTIL 2010-05-31

Statement of Responsibility:

by Paola Rodriguez.

Record Information

Source Institution:

University of Florida

Holding Location:

University of Florida

Rights Management:

Copyright Rodriguez, Paola. Permission granted to the University of Florida to digitize, archive and distribute this item for non-profit research and educational purposes. Any reuse of this item in excess of fair use or other copyright exemptions requires permission of the copyright holder.

Embargo Date:

5/31/2010

Resource Identifier:

664777017 ( OCLC )

Classification:

LD1780 2009 ( lcc )

UFDC Membership

Aggregations:

Institutional Repository at the University of Florida (IR@UF)
University of Florida Theses & Dissertations
University of Florida
INTERNAL UF RETRO ETDS