COOKIES: By using this website you agree that we can place Google Analytics Cookies on your device for performance monitoring. |
University of Cambridge > Talks.cam > DAMTP Astrophysics Seminars > Modelling and interpreting pulsations of rapidly rotating stars
Modelling and interpreting pulsations of rapidly rotating starsAdd to your list(s) Download to your calendar using vCal
If you have a question about this talk, please contact Zhao Guo. The majority of intermediate mass and massive main sequence stars rotate rapidly. This affects their structure, evolution, lifetime, chemical yields, and final outcome. Modelling such stars is highly challenging due to the departure from spherical symmetry and is subject to many uncertainties. Hence, it is necessary to constrain these stars observationally in order to progress in our understanding of them. Asteroseismology, the study of stellar pulsations, is currently the only approach we have at our disposal for probing their internal structure, and is accordingly a particularly important source of information. However, as will be described in this seminar, it is necessary to overcome a number of hurdles to carry out asteroseismic investigations of such stars. First of all, pulsation calculations must be carried out in a 2D context in order to fully include the effects of rotation. The geometry of the resultant pulsation modes can differ substantially from that of their non-rotating counterparts thus leading to a different mode classification. Likewise, the associated pulsation frequency spectra follow new patterns which are more complicated than in the non-rotating case. This leads to the next major hurdle which intervenes when trying to interpret observed pulsation spectra, namely mode identification, i.e. correctly matching theoretical modes with observed pulsation frequencies. Indeed, direct comparisons between the two typically yield multiple solutions due to the high density of theoretical frequencies compared with the observed ones. Therefore, current strategies for interpreting observed pulsations involve looking for specific frequency spacings, such as the large frequency separation and the rotation rate, and/or applying mode identification techniques based on multicolour photometric observations and spectroscopic observations of line profile variations, both of which need to be adapted to the rapidly rotating case. These interpretation strategies will be illustrated through various recent studies of observed stars. This talk is part of the DAMTP Astrophysics Seminars series. This talk is included in these lists:
Note that ex-directory lists are not shown. |
Other listsNumerical Analysis of the Mathematical Modeling of the Mechanics of the Magnetic Fluid Movement under the Influence of Magnetic Force, Based on the Ferrohydrodynamics Principles and Application in Industry and Medicine. Sir Edmund Hillary Memorial Lecture Cosmology, Astrophysics and General RelativityOther talksOral Session 6 Talk 3 Aerosols, Ventilation and the Environment: Competing Agonist-Antagonists The Challenges of Controlling a Quantum Computer Organoids – how can they shed light on immune-mediated development and disease? Adapting the Fokas transform method to solve certain fractional PDEs cISP: A Speed-of-Light Internet Service Provider |