Chemical Abundances in AGN: the Mrk 279 Outflow

Nahum Arav

University of Colorado Boulder

Collaborators:

Jack Gabel, Jelle Kaastra, Gerard A. Kriss, Kirk T. Korista,, Jennifer E. Scott, Daniel Proga,

Katrien C. Steenbrugge, Ehud Behar, Ari Laor, Masao Sako

Using all velocity constraints:

• For Cloudy solar abundances:

C=2.45x10^-4 N=8.5x10^-5 O=4.9x10^-4

• Minimal reduced summed over 15

velocity bins = 4.2 for 44 (75-1-30) dof

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Using all velocity constraints:

• For Cloudy solar abundances:

C=2.45x10^-4 N=8.5x10^-5 O=4.9x10^-4

• Minimal reduced summed over 15

velocity bins = 4.2 for 44 (75-1-30) dof

• For C=2.2 N=3.5 O=1.6 (times solar)

Minimal reduced summed over 15

velocity bins = 1.2 for 41 (75-1-30-3) dof

2

2

Chemical abundances in Mrk 279

• For solar abundances: C=2.45x10^-4 N=8.5x10^-5 O=4.9x10^-4

C=2.2 N=3.5 O=1.6 times solar

90% Confidence interval

C= 1.5—2.9, N=2.4—4.6, O=0.9—2.4

Summary: Modeling AGN outflows

Analysis Key: Accurate Ionic column densities

Obstacles:- The absorber is not an homogeneous full screen!- Velocity dependent covering factor (separate for continuum and BEL)

Solutions- Data needed: Unblended doublets (CNO) and Lyman series, high S/N- Velocity dependent covering-factor and photoionization models

The Mrk 279 outflow: U~-1 (UV) ~0 (X-ray) NH~10^20

Abundances C=2.2 N=3.5 O=1.6 solar units