SUMMARY OF SEQUENCE NUMBER 700172
SUMMARY OF SEQUENCE NUMBER 700172
Title: X-RAY ABSORPTION IN MODERATE REDSHIFT DAMPED LYMAN ALPHA GALAXIES
Observer: BECHTOLD
Subject Category: Active Galaxies and Quasars
Seq: 700172 ObsId: 00867
Long-term Plan bin: 2-Apr-2000
ABSTRACT
We propose to measure the X-ray absorbing column associated with moderate redshift, intervening damped Lyman alpha and 21-cm quasar absorption line systems. The advantage of the X-ray absorption is that it gives a measure of the metal column density (mainly oxygen) and hence abundance, which is independent of ionization, inclusion of the atoms in a molecule, or depletion onto dust grains. We estimate that we will detect absorption if the gas is 1/8 solar or greater for one system at z=0.3 and 1/4 solar or greater for another at z=0.4. For two other objects, we request short exposures with ACIS-S to measure the spectral energy distribution in order to access the feasibility of future grating observations.
TARGET SUMMARY
| TARGET NAME |
RA | DEC |
TIME |
SI |
GRAT |
TYPE |
TC |
ROLL |
PRE |
PHASE |
MULTI |
PRI |
| Q1331+170 |
203.399583 | 16.817611 |
3.000000 |
ACIS-S |
NONE |
GO |
no |
no |
no |
no |
no |
5 |
IMAGES
(NOTE: RASS images currently only available for targets LTS scheduled on or after Apr-09-2000)
PARAMETERS
Obscat Parameters
