Observations of the bright novalike variable IX Velorum with the Hopkins Ultraviolet Telescope

Details Observations of the bright novalike variable IX Velorum with the Hopkins Ultraviolet Telescope Observations of the bright novalike variable IX Velorum with the Hopkins Ultraviolet Telescope

May 1994

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1994apj...426..704l&link_type=abstract

Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 426, no. 2, p. 704-715

Astronomy and Astrophysics

Astronomy

46

Absorption Spectra, Cataclysmic Variables, Spectrum Analysis, Stellar Spectra, Astro Missions (Sts), Astronomical Models, Lyman Alpha Radiation, Lyman Beta Radiation, Stellar Atmospheres, Stellar Winds, Ultraviolet Astronomy, Ultraviolet Telescopes, White Dwarf Stars

Scientific paper

The Hopkins Ultraviolet Telescope, an experiment flown on the Space Shuttle as part of the Astro-1 mission, was used to obtain a spectrum of the novalike variable IX Vel (= CPD -48 deg 1577) in the wavelength range 830-1860 A. The observation revealed a rich absorption-line and continuum spectrum that peaks near 1050 A at a flux of 1.6 x 10-11 ergs/sq cm/s/A. In the sub-Lyman-alpha region, some of the more prominent absorption lines are S VI lambda lambda-933, 945, C III lambda-977, Lyman-beta, O VI lambda lambda-1032, 1038, P V lambda lambda-1118, 1128, and C III lambda-1176. No emission was detected below the Lyman limit. The overall continuum shape of IX Vel in the FUV can be approximated using models of an optically thick accretion disk in which the integrated spectrum has been constructed by summing model stellar atmospheres or proper disk model spectra. However, if the distance to IX Vel is approximately 95 pc, standard disk models without reddening cannot simultaneously reproduce the color and flux in the UV. While interstellar reddening can reconcile this difference, the amount of reddening appears inconsistent with the absence of a 2200 A bump in the spectrum and the very low H I column density measured along the line of sight. Improved fits to the data can be obtained by modifying the accretion disk stucture within three white dwarf radii. None of the models reproduces the profiles of the Li- and Na-like ions, which are observed as strong but relatively narrow absorption lines, and which are almost surely due to a wind above the disk.

Affiliated with

Also associated with

No associations

Rating

Observations of the bright novalike variable IX Velorum with the Hopkins Ultraviolet Telescope 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 Observations of the bright novalike variable IX Velorum with the Hopkins Ultraviolet Telescope, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Observations of the bright novalike variable IX Velorum with the Hopkins Ultraviolet Telescope will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-885010