Spectral Library of Hot Stars with Hubble Space Telescope
Abstract
Libraries of stellar spectra find a plethora of applications, from photometric calibration to stellar population synthesis. We present low resolution spectra obtained with STIS (Space Telescope Imaging Spectrograph) of 40 stars spanning 0.2 to 1.0 micrometers in spectral coverage. The stars include normal O-type stars, helium-burning stars, and post-asymptotic giant branch (PAGB) stars. Observations through three low resolution gratings, G230LB, G430L, and G750L enabled coverage of the wide wavelength interval. Cosmic ray hits, fringing in the red, and scattered light corrections were applied. Cross-correlation was used to bring the spectra to a common, final, zero velocity wavelength scale. Finally, synthetic stellar spectra were used to estimate line of sight dust extinction to each star, and a five-parameter dust extinction model was fit, or a one-parameter fit in the case of low extinction. These spectra dovetail with the similar Next Generation Stellar Library (NGSL) spectra, extending the NGSL's coverage of stellar parameters, and extending to helium burning stars and stars that do not fuse. The fitted dust extinction model showed considerable variation from star to star, indicating variations in dust properties for different lines of sight. Interstellar absorption lines are present in most stars, notably Mg II. The spectra are available at MAST (Mikulski Archive for Space Telescopes) and the CDS (Centre de Données astronomiques de Strasbourg). Support for this work was provided by NASA through grant number HST-GO-14141.001-A from the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555.
- Publication:
-
American Astronomical Society Meeting Abstracts #233
- Pub Date:
- January 2019
- Bibcode:
- 2019AAS...23326403W