1. Heavy Element Abundances in Quasar Absorbers: New Observations with Chandra and HST
Jill Bechtold (University of Arizona)
With: Buell Jannuzi (NOAO), Jeff Valenti (STScI),
Aneta Siemiginowska (CFA), Jennifer Scott (STScI),
Don Schneider (Penn State), Martin Elvis (CFA),
Bob Carswell (Cambridge), Rob Simcoe (Caltech),
Wal Sargent (Caltech)

2. Quasar Absorption Spectroscopy
Intergalactic Medium
ISM of high z galaxies
EUV Radiation background
Observational tests of CDM models for galaxy and LSS formation

3. Dave et al. 1999
Column density of neutral hydrogen
through a 200 km s-1 slice of the LCDM
simulation volume
Red corresponds to NH= cm-2,
orange to NH= cm-2,
yellow to NH= cm-2, and
white to NH>1016 cm-2

4. Dave et al.1999

5. Dave et al.1999

6. dense phase associated with gas in galaxies. Shocked: Hot,
Condensed: Cold,
dense phase associated
with gas in galaxies.
Shocked: Hot,
intermediate-density
phase consisting of
shock-heated gas in
filaments and in
galaxy, group, and
cluster halos.
Diffuse: Cool, low-
density phase associated
with gas whose
temperature is
determined by
photoionization
and adiabatic cooling.
Impey et al. 1999

9. HST Continuous Viewing Zone
Halo Gas -- HVC (complex C)
Two Lyman Limit Systems
IGM

10. Jannuzi et al. 2003

11. X-ray Absorption
Soft X-ray absorption primarily due to => Helium, Carbon and Oxygen
Dust independent .
UV lines are saturated.
H Lya measurements give N(HI) column.
Compare X-ray absorption to Zinc (undepleted) => relative abundance of Fe group to alpha group
Pop II has enhanced O/Fe
M&MC 1983

12. Photoelectric Absorption in X-rays
Redshift Nh
8e20
5e21 O
Z=2
Redshift
z=2
5e21
8e20
z=0.6
Z=0
Z=0

13. Chandra Observations Five damped Ly Alpha systems Different redshifts
High redshift vs. low redshift
QSO zqso zabs N(gal)* N(HI)* Chandra Ref
B Siemiginowska et al
PKS / Bechtold et al
S /-0.6 Turnshek et al
AO / Turnshek et al
PKS Bechtold et al
* 1e21 cm-2

14. Quasar Absorption PKS1127-145 DLA HST/WFPC2 Chandra
Bechtold et al 2001, Siemiginowska et al 2002