Bibcode
DOI
Bresolin, Fabio; Kudritzki, Rolf-Peter; Lennon, Daniel J.; Smartt, Stephen J.; Herrero, Artemio; Urbaneja, Miguel A.; Puls, Joachim
Referencia bibliográfica
The Astrophysical Journal, Volume 580, Issue 1, pp. 213-224.
Fecha de publicación:
11
2002
Revista
Número de citas
17
Número de citas referidas
17
Descripción
We analyze Space Telescope Imaging Spectrograph (STIS) spectra in the
1150-1700 Å wavelength range obtained for six early B supergiants
in the neighboring galaxy M31. Because of their likely high (nearly
solar) abundance, these stars were originally chosen to be directly
comparable to their Galactic counterparts and represent a much needed
addition to our current sample of B-type supergiants, in our efforts to
study the dependence of the wind momentum-luminosity relationship on
spectral type and metallicity. As a first step to determine wind momenta
we fit the P Cygni profiles of the resonance lines of N V, Si IV, and C
IV with standard methods and derive terminal velocities for all of the
STIS targets. From these lines we also derive ionic stellar wind column
densities. Our results are compared with those obtained previously in
Galactic supergiants and confirm earlier claims of ``normal'' wind line
intensities and terminal velocities in M31. For one-half of the sample
we find evidence for an enhanced maximum turbulent velocity when
compared to Galactic counterparts. Based on observations with the
NASA/ESA Hubble Space Telescope obtained at the Space Telescope Science
Institute, which is operated by the Association of Universities for
Research in Astronomy, Inc., under NASA contract NAS5-26555.