The zeta Aurigae stars are the rare but illustrious sub-group of binary stars that undergo the dramatic phenomenon of ‘chromospheric eclipse’. This book provides detailed descriptions of the ten known systemsillustrates them richly with examples of new spectraand places them in the context of stellar structure and evolution.Comprised of a large cool giant plus a small hot dwarfthese key eclipsing binaries reveal fascinating changes in their spectra very close to total eclipsewhen the hot star shines through differing heights of the ‘chromosphere’or outer atmosphereof the giant star. The phenomenon provides astrophysics with the means of analyzing the outer atmosphere of a giant star and how that material is shed into space. The physics of these critical events can be explained qualitativelybut it is more challenging to extract hard facts from the observationsand tough to model the chromosphere in any detail.The book offers current thinking on mechanisms for heating a star’s chromosphere and on how a star loses massand relates this science synergistically to studies of other stars and binariesand to the increasing relevance of contributions from new techniques in interferometry and asteroseismology. It also includes a detailed discussion of the enigmatic star epsilon Aurigaewhich had recently undergone one of its very infrequent and very baffling eclipses. Though not a zeta Aurigae systemepsilon Aurigae is a true ‘Giant’ among eclipsing stars.The 7 chapters of this bookwritten by a group of expertshave been carefully edited to form a coherent volume that offers a thorough overview of the subject to both professional and student.
For many years Dr Griffin pursued research into stellar spectraprincipally of composite-spectrum binariesat Cambridge (UK)supporting it with observations acquired at major telescopes overseas. She now continues those interests in Canadaat the Dominion Astrophysical Observatory near Victoriaand makes her observations there. The prime research objectives are to determine the masses and other fundamental parameters of both component starsand to examine their evolutionary status. She also champions initiatives to recover the information in pre-digital (photographic) observations through programmes of appropriate digitization.Dr. Ake is a Program Director at Computer Sciences Corporation supporting the Hubble Space Telescopethe James Webb Space Telescopethe Milkulski Archive for Space Telescopesand the Kepler Data Management Center projects at Space Telescope Science Institute. His research interests center on evolved stars and binary systemsparticularly UV and FUV spectroscopic investigations from space of red giants and supergiants with hot secondary companions. He is currently studying the evolutionary status of cool stars with main sequence B- and A-type secondaries to refine the fundamental stellar parameters of the evolved components.,
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