Thumbnail
Access Restriction
Open

Author Schmidt, Edward G.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword ASTROPHYSICS, COSMOLOGY AND ASTRONOMY ♦ AMPLITUDES ♦ CEPHEIDS ♦ EMISSION SPECTRA ♦ ENERGY SPECTRA ♦ GRAPHITE ♦ INTERMEDIATE INFRARED RADIATION ♦ INTERSTELLAR GRAINS ♦ IRON ♦ MASS TRANSFER ♦ PHOTOSPHERE ♦ SILICATES ♦ STAR MODELS ♦ STELLAR WINDS
Abstract Spectral energy distributions for 132 classical and type II Cepheids were searched for evidence of excess flux above the photospheric level in the mid-infrared. Eight of them were found to have unambiguously strong excess emission while a further 13 showed evidence of weak emission. The presence of emission appears to be unrelated to either the pulsational amplitude or the effective temperature while strong emission is limited to stars with periods longer than 11 days, with a single exception. For the stars with strong emission we attempted to fit the energy distribution with a stellar wind model. No acceptable fit could be found for silicate grains. With graphite or iron grains we could only obtain an acceptable fit if the maximum dust temperature was significantly lower than the condensation temperature. We conclude that the excess emission is not evidence of mass loss.
ISSN 0004637X
Educational Use Research
Learning Resource Type Article
Publisher Date 2015-11-01
Publisher Place United States
Journal Astrophysical Journal
Volume Number 813
Issue Number 1


Open content in new tab

   Open content in new tab