Hydrodynamic models for pulsating BL Herculis-type variables

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

2

Cepheid Variables, Stellar Oscillations, Hydrodynamic Equations, Stellar Models, Light Curve, Stellar Envelopes, Stellar Temperature, Chemical Composition, Fourier Analysis

Scientific paper

A grid of hydrodynamic limit-cycle models is computed for pulsating BL Her variables with masses of 0.55, 0.6, and 0.65 solar mass, luminosities in the range 106-169 solar luminosities, and effective temperatures in the range 5500-7000 K. The OP tables are used to compute the opacity for the hydrogen and helium mass fractions X = 0.7 and Y = 0.299. Irrespective of the stellar mass, the pulsation instability in the first overtone is typical of stars with pulsation periods less than 1 d, while the radial pulsations for greater than 1 d are attributable to the instability of the fundamental mode. Approximation formulas are derived which relate the pulsation constant to the mass-to-radius ratio (M/R) of the star. It is shown that alternating pulsations with variable amplitude may arise from the 2Pi0 = 3Pi1 resonance between the fundamental mode and the first overtone at certain mass-to-radius ratios.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Hydrodynamic models for pulsating BL Herculis-type variables 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 Hydrodynamic models for pulsating BL Herculis-type variables, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hydrodynamic models for pulsating BL Herculis-type variables will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1770504

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.