The Delta Scuti Stars

The Delta Scuti Stars PDF Author: Michael A. Seeds
Publisher:
ISBN:
Category : Variable stars
Languages : en
Pages : 148

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Book Description

The Delta Scuti Stars

The Delta Scuti Stars PDF Author: Michael A. Seeds
Publisher:
ISBN:
Category : Variable stars
Languages : en
Pages : 148

Get Book Here

Book Description


Amplitude Modulation of Pulsation Modes in Delta Scuti Stars

Amplitude Modulation of Pulsation Modes in Delta Scuti Stars PDF Author: Dominic M. Bowman
Publisher: Springer
ISBN: 3319666495
Category : Science
Languages : en
Pages : 217

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Book Description
This outstanding thesis by Dominic Bowman provides a thorough investigation of long-standing questions as to whether amplitude modulation is astrophysical, whether it offers insights into pulsating stars, and whether simple beating of modes with stable amplitudes is unrecognised because of a lack of frequency resolution. In this thesis, the author studied a uniform sample of 983 delta Scuti stars—the most common type of main-sequence heat engine pulsator—that were observed nearly continuously for 4 years at stunning photometric precision of only a few parts per million by the Kepler space mission. With no mission planned to supersede the Kepler 4-year data set, this thesis will stand as the definitive study of these questions for many years. With revolutionary photometric data from the planet-hunting Kepler space mission, asteroseismic studies have been carried out on many hundreds of main-sequence solar-type stars and about 10,000 red giants. It is easy to understand why those stochastically driven stars have highly variable amplitudes. Over much of the rest of the Hertzsprung–Russell (HR) diagram, stellar pulsations are driven by heat mechanisms, which are much more regular than the stochastic driving in solar-like pulsators. Yet for decades, amplitude and frequency modulation of pulsation modes have been observed in almost all types of heat-driven pulsating stars. The author shows that the amplitude and frequency modulation are astrophysical, and he has investigated their implications and prospects to provide new insights into the delta Scuti stars and the many other types of heat-engine pulsators across the HR diagram.

An Investigation of the Delta Scuti Stars

An Investigation of the Delta Scuti Stars PDF Author: Robert L. Millis
Publisher:
ISBN:
Category : Variable stars
Languages : en
Pages : 346

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Delta Scuti and Related Stars

Delta Scuti and Related Stars PDF Author: Michel Breger
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 632

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Book Description
Annotation Contains 35 papers presented as part of the August 1999 workshop. The opening papers review photometric techniques, spectroscopic techniques, and theoretical modeling of the pulsations. Shorter contributions discuss such topics as double-mode SX phoenicis variables in globular clusters, convective effects on p-mode stability in delta Scuti stars, problems encountered in the Hipparcos variable stars analysis, and a list of delta Scuti stars and their associated parameters. No subject index. Annotation c. Book News, Inc., Portland, OR (booknews.com)

Pulsating Stars

Pulsating Stars PDF Author: Márcio Catelan
Publisher: John Wiley & Sons
ISBN: 3527407154
Category : Science
Languages : en
Pages : 500

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Book Description
This book surveys our understanding of stars which change in brightness because they pulsate. Pulsating variable stars are keys to distance scales inside and beyond the Milky Way galaxy. They test our understanding not only of stellar pulsation theory but also of stellar structure and evolution theory. Moreover, pulsating stars are important probes of the formation and evolution of our own and neighboring galaxies. Our understanding of pulsating stars has greatly increased in recent years as large-scale surveys of pulsating stars in the Milky Way and other Local Group galaxies have provided a wealth of new observations and as space-based instruments have studied particular pulsating stars in unprecedented detail.

Understanding Variable Stars

Understanding Variable Stars PDF Author: John R. Percy
Publisher: Cambridge University Press
ISBN: 1139463284
Category : Science
Languages : en
Pages : 330

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Book Description
This book was first published in 2007. Variable stars are those that change brightness. Their variability may be due to geometric processes such as rotation, or eclipse by a companion star, or physical processes such as vibration, flares, or cataclysmic explosions. In each case, variable stars provide unique information about the properties of stars, and the processes that go on within them. This book provides a concise overview of variable stars, including a historical perspective, an introduction to stars in general, the techniques for discovering and studying variable stars, and a description of the main types of variable stars. It ends with short reflections about the connection between the study of variable stars, and research, education, amateur astronomy, and public interest in astronomy. This book is intended for anyone with some background knowledge of astronomy, but is especially suitable for undergraduate students and experienced amateur astronomers who can contribute to our understanding of these important stars.

The Rotation of Sun and Stars

The Rotation of Sun and Stars PDF Author: Jean-Pierre Rozelot
Publisher: Springer Science & Business Media
ISBN: 3540878300
Category : Science
Languages : en
Pages : 266

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Book Description
The Sun and stars rotate in di?erent ways and at di?erent velocity rates. The knowledge of how they rotate is important in understanding the formation and evolution of stars and their structure. The closest star to our Earth, the Sun, is a good laboratory to study in detail the rotation of a G star and allows to test new ideas and develop new techniques to study stellar rotation. More or less massive, more or lessevolved objects, however, can have averydi?erent rotation rate, structure and history. In recent years our understanding of the rotation of the Sun has greatly improved. The Sun has a well-known large-scale rotation, which can be m- sured thanks to visible features across the solar disk, such as sunspots, or via spectroscopy. In addition, several studies cast light on di?erential rotation in the convective zone and on meridional circulation in the radiative zone of the Sun. Even the rotation of the core of the Sun can now be studied thanks to various methods, such as dynamics of the gravitational moments and of course, helioseismology, through g-modes analysis. Moreover, the magnetic ?eld is strongly linked to the matter motions in the solar plasma. The solar magnetic ?eld can be measured only at the surface or in theupperlayers.Itistheproductoftheinternaldynamoorofthelocaldynamos if they exist – in any case magnetic ?eld and rotation cannot thus be separated.

A Dictionary of Astronomy

A Dictionary of Astronomy PDF Author: Ian Ridpath
Publisher: Oxford University Press
ISBN: 0192542613
Category : Science
Languages : en
Pages : 931

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Book Description
Compiled with the help of over 20 expert contributors under the editorship of renowned author and broadcaster Ian Ridpath, the third edition of A Dictionary of Astronomy covers everything from space exploration and the equipment involved, to astrophysics, cosmology, and the concept of time, in over 4,300 entries. The dictionary also includes biographical entries on eminent astronomers, as well as worldwide coverage of observatories and telescopes. Supplementary material is included in the appendices, such as tables of Apollo lunar landing missions, the constellations, planetary data, and numerous other tables and diagrams complement the entries. The entries have been fully revised and updated for this edition, and more than 100 new entries have been added to reflect the recent developments within the field of astronomy, including Bennu, Euclid, Mars Orbiter Mission, and slowly pulsating B star. A Dictionary of Astronomy is an invaluable reference source for students, professionals, amateur astronomers, and space enthusiasts.

Nonlinear Phenomena in Stellar Variability

Nonlinear Phenomena in Stellar Variability PDF Author: Mine Takeuti
Publisher: Springer Science & Business Media
ISBN: 940111062X
Category : Science
Languages : en
Pages : 344

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Book Description
The nonlinear theory of oscillating systems brings new aspects into the study of variable stars. Beyond the comparison of linear periods and the estimate of stability, the appearance and disappearance of possible modes can be studied in detail. While nonlinearity in stellar pulsations is not a very complicated concept, it generally requires extensive and sometimes so phisticated numerical studies. Therefore, the development of appropriate computational tools is required for applications of nonlinear theory to real phenomena in variable stars. Taking trends in variable star studies into consideration, the International Astronomical Union organized a colloquium for the nonlinear phenomena of variable stars at Mito, Japan in 1992. The colloquium served to give an overview of the new frontiers of variable star studies and to encourage further development of this field. The colloquium covered the fundamental theory, interesting observational facts, and the numerical modeling. The publication of the proceedings was somewhat delayed since one of the editors, M. T., was overwhelmed by administrative work. We are sorry that the excellent reviews of Drs. H. :Mori, M. Sano, and K. Makishima cannot be found in the proceedings. We also miss the summary given by Dr. W. W. Dziembowski. Throughout the editing procedure Dr. Y. Tanaka of Ibaraki University kindly helped us. Because of the unfortunate delay of the publication~ the significance of several papers may be affected. Even so, we believe that the papers are useful to variable star researchers because of their scientific importance.

Challenges of asteroseismology in the era of space missions

Challenges of asteroseismology in the era of space missions PDF Author: Javier Pascual Granado
Publisher: Frontiers Media SA
ISBN: 283251152X
Category : Science
Languages : en
Pages : 157

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Book Description