RV Tauri stars. I. A long-term photometric survey.

Other

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

33

Surveys -- Stars: Agb And Post-Agb -- Stars: Oscillations -- Stars: Variables: Other, Rv Tauri Stars: Photometry, Rv Tauri Stars: Light Curves, Rv Tauri Stars: Periods, Rv Tauri Stars: Pulsation Theory

Scientific paper

A programme of photometric and spectroscopic observations has been undertaken in order to investigate the physical characteristics of the RV Tauri variables. This paper presents and discusses the results from the photometric survey. Long time baseline BVRI photometry has been obtained at the Mt John University Observatory (MJUO) over intervals of between 750 and 1300 d for eleven of the RV Tauri variables. RV Tauri stars from both the RVa (constant mean magnitude) and RVb (varying mean magnitude) photometric subclasses and from all three spectroscopic Preston subtypes (A, B and C types) were included in the programme. Fourier and least-squares analyses of the light and colour variations reveal the dominant periodicities and the stability of the pulsations in these stars. A harmonic (f+2f) fit is found to be a good representation of the "deep-shallow" nature of both the light and colour curves in most stars. The derived photometric characteristics have been used to examine a number of theoretical models that attempt to describe the pulsation mechanisms and physical parameters of the RV Tauri stars. The nonlinear, hydrodynamic calculations by Fokin show that low-mass, low-metallicity and high-luminosity models can reproduce the correct RV Tauri periods, amplitudes and alternating character. The Fourier spectra from the analysis of the MJUO photometry (which indicate two dominant peaks with a frequency ratio close to 2:1) and the theoretical RV Tauri models of Fokin and Tuchman et al. lend support to the earlier proposal by Takeuti and Petersen that the alternating light curve in these stars may arise from a 2:1 resonance between the fundamental and first overtone modes.

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

RV Tauri stars. I. A long-term photometric survey. 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 RV Tauri stars. I. A long-term photometric survey., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and RV Tauri stars. I. A long-term photometric survey. will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1108040

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