| Type |
Conference Paper |
| Names |
Anand Narayanan, B. Savage, B. Wakker, Y. Yao, C. Danforth, C. Froning, J. Green, B. Keeney, K. Sembach, M. Shull |
| Proceedings Title |
Bulletin of the American Astronomical Society |
| Conference Name |
American Astronomical Society, AAS Meeting #215, #460.05 |
| Volume |
42 |
| Pages |
490 |
| Date |
January 1, 2010 |
| URL |
http://adsabs.harvard.edu/abs/2010AAS...21546005N |
| Library Catalog |
NASA ADS |
| Abstract |
The high S/N COS spectrum of the UV bright quasar PKS0405-123 provides
the sensitivity required for a search of Ne VIII in QSO metal line
absorption systems at z > 0.47. The EUV lines of Ne VIII 770,780 A
are ideal tracers of hot collisionally ionized gas at T (0.5 - 1) x
106 K. However, detecting these weak lines require spectra of
good S/N in which the effects of detector fixed pattern noise are well
understood. The z = 0.49510 O VI multiphase metal line absorption system
along this sight line is ideally suited for a search for Ne VIII. Chen
& Mulchaey (2009) have identified an emission line galaxy of
extended morphology at a projected physical separation of 77 kpc from
this absorber. The COS spectrum provides coverage of O II 834, O III
833, O IV 788, C III 977 and higher order Lyman series lines associated
with this absorber at a much higher S/N than the FUSE and STIS
observations for this target. The improved line measurement based on the
COS spectrum, combined with the information on O VI from STIS is used to
derive detailed physical conditions in the multiple gas phases of this
absorber. Evidence for the presence of shock-heated gas would imply that
the absorber is tracing either transition temperature gas in the
galaxy's halo or an intergalactic WHIM filament connecting galaxies as
part of the large scale structure.
This research has been supported by the NASA Cosmic Origins Spectrograph
Program through a sub-contract to the University of Wisconsin from the
University of Colorado. |