Determining cloud parameters with the Curve-of-Growth: Application Eta Car

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

We have investigated the NUV part of the Eta Car spectrum, using data with high spatial and high spectral resolving power obtained with the HST/STIS under the Treasury Program (K. Davidson P.I.). The NUV spectrum of Eta Car shows a great contribution of absorption features from neutral and singly ionized elements along the line-of-sight. A large number of velocity systems have been observed. The two most prominent, with Doppler shifts corresponding to -146 and -513 km/s respectively, are shown to be useful for investigations of the gaseous environments responsible for the absorption. The -146 and the -513 km/s velocity systems display different characteristics regarding the ionization state and spectral line width, which suggest that they originate at different distances from the central object.
We have investigated the absorption structures before the spectroscopic minimum, occurring during the summer of 2003, with a standard curve-of-growth. We have independently derived the column density and the b-value for the Fe II (-146 km/s) and Ti II (-513 km/s) velocity systems. The excitation temperature has been determined for the -146 km/s velocity system using the photo-ionization code \textsc{cloudy} (Ferland 1996, Ferland et al. 2000). The -146 km/s velocity structure shows noticeable variation over the spectroscopic minimum. The sudden appearance and disappearance of Ti II and V II are astonishing. We have made an attempt to analyze these variations with the curve-of-growth method and will present preliminary results.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Determining cloud parameters with the Curve-of-Growth: Application Eta Car does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Determining cloud parameters with the Curve-of-Growth: Application Eta Car, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Determining cloud parameters with the Curve-of-Growth: Application Eta Car will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1420721

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.