eprintid: 23301
rev_number: 19
eprint_status: archive
userid: 3256
dir: disk0/00/02/33/01
datestamp: 2017-08-17 09:33:19
lastmod: 2017-08-23 11:47:49
status_changed: 2017-08-17 09:33:19
type: doctoralThesis
metadata_visibility: show
creators_name: Schnülle, Kirsten
title: Studying the Radiative Response of Circumnuclear Dust of AGNs
subjects: ddc-500
subjects: ddc-520
subjects: ddc-530
divisions: i-130200
adv_faculty: af-13
cterms_swd: AGN
cterms_swd: Dust
cterms_swd: Reverberation
abstract: Radius measurements of dust tori around the central engine of luminous active galaxies
open up the possibility of probing cosmological models out to redshifts beyond where supernovae
can be used. Yet, the value of dust tori as standard candles is constrained by
the substantial intrinsic scatter in the size-luminosity relation found for samples of AGNs.
Indicated by single objects, a probable cause of this scatter is a non-trivial variation in the
dust location with the luminosity of the central engine, due to sublimation events and subsequent
long-term reformation of the hot dust surface radiating at near-infrared wavelengths.
In this work, I developed a refined dust reverberation model allowing to measure torus
sizes and additional observables characterizing the temperature state, stability, and distribution
of the innermost, hot dust in AGNs.
Optical to near-infrared photometric data were observed for 24 type 1 AGNs. Of these, I
have analyzed the Seyfert 1 galaxies NGC 4151, Ark 120, NGC 5548, and NGC 3227. The
derived inner torus radii fit very well into the established size-luminosity relation. While
three objects are well-described by a standard model without sublimation, the data of one
object could be fit satisfactorily only after allowing for dust sublimation events in the model.
date: 2017
id_scheme: DOI
id_number: 10.11588/heidok.00023301
ppn_swb: 1654583294
own_urn: urn:nbn:de:bsz:16-heidok-233013
date_accepted: 2017-07-27
advisor: HASH(0x559e37d33910)
language: eng
bibsort: SCHNULLEKISTUDYINGTH2017
full_text_status: public
place_of_pub: Heidelberg, Deutschland
citation:   Schnülle, Kirsten  (2017) Studying the Radiative Response of Circumnuclear Dust of AGNs.  [Dissertation]     
document_url: https://archiv.ub.uni-heidelberg.de/volltextserver/23301/1/Thesis_KSchnuelle_final.pdf