Title: Mass Outflow in the Seyfert 1 Galaxy NGC 4151
1Mass Outflows from AGN in Emission and Absorption
Mike Crenshaw (Georgia State University) Steve
Kraemer (Catholic University of America) Jack
Gabel (University of Colorado)
2UV/X-ray Observations of NGC 4151
NGC 4151 O III Image
3History of UV Continuum Variations (21 Years)
IUE black pluses HUT red diamonds FOS green
triangles STIS blue xs
4Absorption Components in STIS and FUSE Spectra
- A, C, DE, E? are intrinsic B is Galactic F, F?
are host galaxy. - DE (vr -500 km s-1) responsible for bulk of UV
and X-ray absorption.
5Variability in C IV Region
(Kraemer et al. 2006, in preparation)
- DE varies strongly in the low-ionization lines
(e.g., Si II) - DE in 2002 is much weaker than expected from
ionization changes
6Variability of DE Absorption (1999 - 2002)
- EW of low-ionization lines generally
anti-correlated with continuum
? ionization changes (high-ionization lines
are saturated) - Low EW in last observation indicates change in
column density. ? transverse motion vT
1250 km s-1
7Emission-Line Profiles at Low Flux Levels
He II
- He II profile has two components (broad component
not detected) - narrow 260 km s-1 FWHM, intermediate
1150 km s-1 FWHM
8Emission-Line Profiles at Low Flux Levels
C IV
- Fit to C IV profile using He II components (plus
broad-line profile) - DE absorbs intermediate component ? self
absorption? (P-Cygni like) ?
likely the absorber in emission
9Photoionization Models 2002 STIS, FUSE, CXO
Observations
- DEb responsible for most of the metastable C
III. ? distance 0.1pc - DEa is responsible for high-ionization UV lines
and most of the X-ray absorption, and must screen
DEb ? distance 0.1pc - DEc needed for low Clos of P V, etc.
(distance unknown)
10Conclusions
- The outflowing UV absorbers in NGC 4151 vary as a
result of both changing ionization and motion
across the line of sight. - Component DE is responsible for the bulk of the
UV and X-ray absorption, and has several physical
subcomponents (a-c). - Most of DE is only 0.1 pc from the central
source (compared to tens of pcs for many UV/X-ray
absorbers). - DE (at vr 500 km s-1) has a transverse
velocity 1250 km s-1, similar to the rotation
velocity at 0.1 pc (720 km s-1). - We have detected DE in emission, which yields a
global covering factor of 0.35 - 0.8. - This component provides the best case for a
rotating accretion disk wind in a Seyfert galaxy.