Intrinsic Absorption of Mrk 279 The Variable UV Intrinsic Absorption of Mrk 279 Jennifer E. Scott NRC/NASA/GSFC N. Arav, J. Gabel (CASA/CU) G. Kriss, J. Kim Quijano (STScI)

Mrk 279 Observations Summary Date Instrument ksec 1999 Dec FUSE 61 2000 Jan 30 2002 Jan 37 2002 May 47 STIS/E140M 13 CXO/HETGS 114 2003 May 91 41 CXO/LETGS 340 Two sets of coordinated observations How do changes in emission components impact absorption profiles? Photoionization Effective Covering fraction (lines vs .continuum, or ILR vs. BLR )

Continuum Variability Dec. 1999 Flux May 2003 Jan. 2000 Jan., May 2002 Spectral index

Mrk 279 Seyfert 1 galaxy z=0.0305 Five velocity components of UV absorption Most likely intrinsic absorption -300 < vout< -200 km/s Scott et al. 2004, Gabel et al. 2005

Absorption Profile with Multiple Emission Sources Each source i (continuum, BLR, etc.) contributes Ri to total flux at pixel j Effective covering fraction is a weighted sum of individual covering fractions Gabel et al. 2005, Scott et al. 2004

Change in Lyman alpha absorption profile can be explained by change in relative contribution of continuum and BLR No change in covering fraction or column density necessary Gabel et al. 2005

Global CNO Fits to 2003 Spectra Gabel et al. 2005

Relative contribution of emission lines is larger in 2002 low flux state

Can changes in O VI, N V, and C IV be explained in a similar way? Use well-constrained 2003 covering fractions, column densities Try to reproduce 2002 profiles by: Allowing the covering fraction of the intermediate line region (ILR) to be different from that of the BLR. (See emission profiles below) (2) Vary the column densities according to changes in the ionizing flux (photoionization models)

Relative contributions of ILR and BLR change with continuum level

Relative contributions of ILR and BLR change with continuum level

Relative contributions of ILR and BLR change with continuum level

Photoionization Models: Spectral Energy Distributions

Photoionization Models: 2002/2003 Column Density Ratios

O VI: Compare 2002 profiles to variations on 2003 Cc, CBLR, N solutions

N V: Compare 2002 profiles to variations on 2003 Cc, CBLR, N solutions

C IV : Compare 2002 profiles to variations on 2003 Cc, CBLR, N solutions

For -300 < vout < -200 km/s absorption 2002 (low state) vs. 2003 (high state): O VI: CILR = 0, saturation -> N(O VI) unconstrained N V CILR = 0.5 CBLR, same N(N V) -or- 0 < CILR < 0.5 CBLR, larger N(N V) in 2002 vs. 2003 C IV C ILR= C BLR, same N(C IV) -or- 0.5 CBLR< C ILR < C BLR, larger N(C IV) in 2002 vs. 2003 Problem with C III?

Expect the column density to vary by a factor of up to ~1000 for observed changes in ionizing flux. However, profile changes little, particularly over -300 < vout < -200 km/s