The vertical BLR structure in nearby AGN

32 Pages·2014·3.76 MB·English

by  Klaus Jaeger

TThhee  vveerrttiiccaall  BBLLRR  ssttrruuccttuurree  iinn  nneeaarrbbyy  AAGGNN  
Wolfram Kollatschny, Göttingen
Austin, 2014
Bev and I, summer 96
BBrrooaadd eemmiissssiioonn lliinnee pprrooffiilleess ccoonnttaaiinn iinnffoorrmmaattiioonn oonn
tthhee kkiinneemmaattiiccss aanndd ssttrruuccttuurree ooff tthhee lliinnee eemmiitttt.. rreeggiioonnss
Line profiles can be parametrized by their FWHM, line dispersion σ, or their
ratio FWHM/σ of the mean or rms line profiles.
Peterson et al., 2004 Mrk110 Kollatschny, 2003
LLiinnee--wwiiddtthh rraattiiooss FFWWHHMM//σσ ffoorr ddiiffffeerreenntt lliinnee pprrooffiilleess
Different motions lead to different emission line profiles.
Relationship between FWHM and
σ depends on the line profile:
FWHM/σ
- rectangular fct. 3.46
- edge-on rotat. ring 2.83
- Gaussian profile 2.35
- exponent. profile √2*ln2≈0.98
- logarithmic profile → 0.
- Lorentzian profile → 0.
HHββ lliinnee--wwiiddtthh rraattiioo FFWWHHMM//σσ vveerrssuuss σσ
FWHM/σ observations of a data set of 35 variable AGN (from Peterson et al., 2004)
Collin et al., 2006
Relationship between FWHM and σ :
FWHM/σ
- rectangular fct. 3.46
- edge-on rotat. ring 2.83
- triangular fct. 2.45
- Gaussian profile 2.35
- Lorentzian profile → 0.
Open and filled circles correspond  to values based on mean and rms spectra.                                                   
  The vertical line at σ = 2000 km/s approximates the division of Sulentic et al. (2000) into Populations A ( left) and B  
( right).                                                                                                                                                                                 
The horizontal line at 2.35 divides the samples into Populations 1 ( lower) and 2 ( upper)         (Collin et al., 2006).
H H ββ lliinnee--wwiiddtthh rraattiiooss:: FFWWHHMM//σσ vvss.. σσ oorr vvss.. FFWWHHMM
Kollatschny & Zetzl, 2011, Nature 470
Collin et al., 2006
Hβ
The Hβ line-width ratio FWHM/σ
versus σ (mean & rms profiles).
Kollatschny & Zetzl: The Hβ line-width
ratio FWHM/σ versus FWHM (rms profiles)
HHeeIIII aanndd CCIIVV lliinnee--wwiiddtthh rraattiiooss FFWWHHMM//σσ vveerrssuuss FFWWHHMM
From Peterson (2004) data set:
The HeIIλ4686 line-width ratio FWHM/σ The CIVλ1549 line-width ratio FWHM/σ versus
versus FWHM (rms profiles). FWHM (rms profiles).  
Kollatschny & Zetzl, 2011, Nature 470
Different emission lines show similar – however different – systematics
in the line profile relations.
LLiinnee--wwiiddtthh rraattiioo ssttuuddiieess
Observed Hβ, HeII and CIV line-width ratios FWHM/σ versus linewidth FWHM.
narrow prof.: steep
broad prof.: flat
Reproducing the observed trend(s) by simple convolution of few line profile types:
MMooddeelliinngg ooff oobbsseerrvveedd lliinnee pprrooffiillee rreellaattiioonnss →→ FFWWHHMM,, σσ
Tests: Theoretical line broadening of a Gaussian profile due to rotation
and Doppler broadening of a Lorentzian profile .
Rotational broadening of  a Gaussian Hβ line  D  oppler line broadening of Lorentzian Hβ  
profile  (v  = 500 km/s).   profile  (v  = 500 km/s).  
Doppler turb
MMooddeelliinngg ooff oobbsseerrvveedd lliinnee pprrooffiillee rreellaattiioonnss
in simple way by multiple combinations of profiles.

Observed and theoretical Hβ line-width ratios FWHM/σ versus FWHM
Lorentzian profiles convolved with Rotational broadening of Gaussian profiles.
Gaussian profiles. The line widths of the Gaussian profiles (FWHM)
The line widths of the Lorentzian profiles correspond to 500, 1000,..., 8000 km/s (from top to
(FWHM) correspond to 50, 100, 500, 1000, bottom). The associated rotational velocities range
2000, 3000 km/s (from top to bottom). The from 1000 to 7000 km/s (from left to right).
widths of the Gaussian profiles correspond to FWHM/σ always larger than 2.35.
1000 to 9000 km/s (from left to right).

Kollatschny & Ze tzl, 2011, Nature 470
MMooddeelliinngg tthhee lliinnee bbrrooaaddeenniinngg dduuee ttoo rroottaattiioonn
The rotational velocity b=Δλ/x is by definition the half width at zero
intensity (HWZI) of an ellipsoidal profile (Unsoeld, 1955):
Line broadening formula:

W: intrinsic line profile without rotational broadening, A: rotational profile
S: convolved profile