AAS 199th meeting, Washington, DC, January 2002
Session 135. Circumstellar Material and Atmospheres: Hotter
Display, Thursday, January 10, 2002, 9:20am-4:00pm, Exhibit Hall

[Previous] | [Session 135] | [Next]

[135.15] Optical - IR stellar astrophysics: Models vs. Observations

J.W. Ferguson, J.J. Penley, D.R. Alexander (Wichita State University), F. Allard (CRAL-ENS, Lyons, France), P.H. Hauschildt (University of Georgia, Athens)

Recent observational catalogs by Lancon & Wood (2000, A&AS, 146, 217) and Pickles (1998, PASP, 110, 863) among others include the spectra of dozens of stars covering an unprecedented wavelength range from the optical to near-infrared. These observations include a wide range of stellar temperatures, and many types of stars including some with unusual chemical compositions. Such observations are a vast improvement over previous "optical-only" or "infrared-only" spectra. Having good observations with such a broad wavelength range make it possible to better model the conditions of these stars. Carefully fitting the effects of molecules such as H2O, CO, VO, and TiO in the spectra of these stars is paramount in our effort to better understand these stars.

We show the results of PHOENIX (Hauschildt & Baron, 1999, J. Comp. Appl. Math., 102, 41) stellar atmosphere models with recent improvements in the TiO, H2O and a few other minor molecular opacity sources. Models computed with different sources of molecular opacity (H2O for example) show varying degrees of accuracy of fit, although none of the sources given are perfect fits to the observed spectral shape. Comparisons with the observations are made and the resulting effective temperature/spectral class scale is shown.

Low temperature astrophysics at Wichita State University is supported by NSF grant No. EPS-9874732 with matching support from the State of Kansas, by a NASA EPSCoR grant NCC5-168 and NASA LTSA grant NAG5-3435.

If you would like more information about this abstract, please follow the link to http://webs.wichita.edu/physics/ferguson/. This link was provided by the author. When you follow it, you will leave the Web site for this meeting; to return, you should use the Back comand on your browser.

The author(s) of this abstract have provided an email address for comments about the abstract: mailto:jason.ferguson@wichita.edu

[Previous] | [Session 135] | [Next]