Bump masses for BL Her stars Metadata

Metadata describes a digital item, providing (if known) such information as creator, publisher, contents, size, relationship to other resources, and more. Metadata may also contain "preservation" components that help us to maintain the integrity of digital files over time.

Available Formats

Dublin Core: XML Dublin Core: JSON Dublin Core: Text Dublin Core: RDF/XML UNTL: XML Access METS: XML

Title

  • Main Title Bump masses for BL Her stars

Creator

  • Author: Davis, C.G.
    Creator Type: Personal

Publisher

  • Name: Los Alamos National Laboratory
    Place of Publication: New Mexico

Date

  • Creation: 1982-01-01

Language

  • English

Description

  • Content Description: The masses of classical Cepheids can be determined by using the phase of the Hertzsprung bump on the light or velocity curve, Cox-Stewart opacities, and nonlinear pulsation theory. The fact that these bump masses are some 60% lower than the evolutionary masses raises some questions about this approach. In support of our method, we calculate the light curve for BL Her, a population II Cepheid, with an observed bump on the declining portion of its light curve. The nonlinear hydrodynamic model we use (Davis and Davison - 1978) resolves the light curve by dynamic zoning and allows us the opportunity to make a direct comparison of the calculated light curve to the observations, using a prescribed mass, luminosity and effective temperature. The parameters for BL Her are from a linear model (Hodson, Cox, and King - 1982) that has nearly the correct period (1./sup d/2) and the correct period ratio from resonance theory (..pi../sub 2//..pi../sub 0/ = 0.53) for a bump to appear on the declining portion of the light curve as observed. These parameters are: M = 0.55 M, L = 95.0 L, and T/sub eff/ = 6500 K. This mass is near the evolutionary mass as described by Schwartzschild and Haerm (1970). The model results agree well with the observations and the color-T/sub eff/ relation has the same slope as that observed for RR Lyrae stars by the Oke, Giver and Searle (1965) relationship.
  • Physical Description: 6 pages

Subject

  • Keyword: Hydrodynamic Model
  • Keyword: Star Models
  • Keyword: Thermodynamic Model 640102* -- Astrophysics & Cosmology-- Stars & Quasi-Stellar, Radio & X-Ray Sources
  • Keyword: Pulsations
  • Keyword: Variations
  • Keyword: Mathematical Models
  • Keyword: Mass
  • STI Subject Categories: 71 Classical And Quantum Mechanics, General Physics
  • Keyword: Particle Models
  • Keyword: Statistical Models
  • Keyword: Binary Stars
  • Keyword: Stars

Source

  • Conference: Conference on pulsations in classical and cataclysmic variable stars, Boulder, CO, USA, 1 Jun 1982

Collection

  • Name: Office of Scientific & Technical Information Technical Reports
    Code: OSTI

Institution

  • Name: UNT Libraries Government Documents Department
    Code: UNTGD

Resource Type

  • Article

Format

  • Text

Identifier

  • Other: DE82019564
  • Report No.: LA-UR-82-2008
  • Report No.: CONF-8206101-2
  • Grant Number: W-7405-ENG-36
  • Office of Scientific & Technical Information Report Number: 5100744
  • Archival Resource Key: ark:/67531/metadc1061218

Note

  • Display Note: NTIS, PC A02/MF A01.
Back to Top of Screen