Angular Momentum Evolution of Young Stars

Angular Momentum Evolution of Young Stars PDF Author: S Catalano
Publisher: Springer Science & Business Media
ISBN: 9401135800
Category : Science
Languages : en
Pages : 462

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Book Description
This book reports the Proceedings of the NATO Advanced Research Workshop on "An gular Momentum Evolution of Young Stars" held from 17 to 21 September 1990 at Noto, Italy. The workshop had its immediate origin in a discussion about the availability of stel lar rotation data, that took place in 1987 at Viana do Castelo Portugal during the NATO meeting, Formation and Evolution of Low Mass Stars. We recognized that nearly 20 years had passed since the last meeting on stellar rotation and that significant progress in the observation of rotation rates in low mass stars had been made. During the last 20 years, new efficient instrumentation (CCD and photon counting de tectors and echelle spectrographs) and new analysis techniques (profile Fourier analysis) have allowed us to measure rotational velocities as low as 1-2 km/s and to reach low mass stars in young clusters. Even with these advances, rotational velocities of low mass stars would have remained challenging to determine if all single, low mass stars later than GO had rotational velocities of order or less than 10 km/sec. Evidence that this is not always the case was first provided by the photometric variability data obtained by van Leeuwen and Alphenaar for K dwarfs in the Pleiades and more recently by the vsini measurements of low mass stars in several young clusters.

Angular Momentum Evolution of Young Stars

Angular Momentum Evolution of Young Stars PDF Author: S Catalano
Publisher: Springer Science & Business Media
ISBN: 9401135800
Category : Science
Languages : en
Pages : 462

Get Book

Book Description
This book reports the Proceedings of the NATO Advanced Research Workshop on "An gular Momentum Evolution of Young Stars" held from 17 to 21 September 1990 at Noto, Italy. The workshop had its immediate origin in a discussion about the availability of stel lar rotation data, that took place in 1987 at Viana do Castelo Portugal during the NATO meeting, Formation and Evolution of Low Mass Stars. We recognized that nearly 20 years had passed since the last meeting on stellar rotation and that significant progress in the observation of rotation rates in low mass stars had been made. During the last 20 years, new efficient instrumentation (CCD and photon counting de tectors and echelle spectrographs) and new analysis techniques (profile Fourier analysis) have allowed us to measure rotational velocities as low as 1-2 km/s and to reach low mass stars in young clusters. Even with these advances, rotational velocities of low mass stars would have remained challenging to determine if all single, low mass stars later than GO had rotational velocities of order or less than 10 km/sec. Evidence that this is not always the case was first provided by the photometric variability data obtained by van Leeuwen and Alphenaar for K dwarfs in the Pleiades and more recently by the vsini measurements of low mass stars in several young clusters.

Star-Disk Interaction in Young Stars (IAU S243)

Star-Disk Interaction in Young Stars (IAU S243) PDF Author: International Astronomical Union. Symposium
Publisher: Cambridge University Press
ISBN: 9780521874656
Category : Science
Languages : en
Pages : 396

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Book Description
Reviews latest star-disk interaction region in young stars for graduate students and researchers.

Angular Momentum and Mass Loss for Hot Stars

Angular Momentum and Mass Loss for Hot Stars PDF Author: L.A. Willson
Publisher: Springer Science & Business Media
ISBN: 9400921055
Category : Science
Languages : en
Pages : 366

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Book Description
Fundamental unsolved problems of stellar astrophysics include the effects of angular momentum on stellar structure and evolution, the nature and efficiency of the processes by which angular momentum is redistributed within and lost from stars, and the role that stellar rotation plays in enhancing or driving stellar mass loss. There appears to be a qualitative change in the nature and efficiency of these mechanisms near spectral type FO: hotter (more massive) stars typically retain more angular momentum at least until they reach the main sequence, while cooler stars typically spin down quickly. For the hotter stars, recent work suggests a strong link between the type of pulsation behavior, the mass loss rates, and the rotation velocity. If the same mechanisms are able to drive mass loss from the main sequence A stars, as has recently been proposed, then the current interpretations of a number of observations will be drastically affected: e. g. the ages of clusters may be incorrect by up to a factor of two, and the surface abundances of isotopes of He, Li and Be may no longer give constraints on cosmological nucleosynthesis. There are also effects on the evolution of the abundances of elements in the interstellar medium and on the general evolution of populations of stars. Thus the questions of the mechanisms of angular momentum and mass loss of stars more massive than the sun is important not only for stellar studies but for the foundations of much of modern astrophysics.

Star-Disk Interaction in Young Stars (IAU S243)

Star-Disk Interaction in Young Stars (IAU S243) PDF Author: Jerome Bouvier
Publisher: Cambridge University Press
ISBN: 9780521874656
Category : Science
Languages : en
Pages : 0

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Book Description
Stars form surrounded by a circumstellar disk which is thought to be the cradle of planets. IAU Symposium 243 highlights the latest developments in understanding the structure and evolution of the star-disk interaction region in young stars, a critical component of our knowledge of star and planetary system formation processes. Discussions review the physical processes thought to be at work at the star-disk interface, confront the predictions of the latest numerical and analytical magnetohydrodynamic models of star-disk-jet systems with observations, and explore the consequences of these processes for stellar angular momentum evolution and inner disk structure. The most recent observational results, computer simulations and theoretical developments in this active field of research are included to provide a unique vision into this central aspect of the star and planet formation problem.

Literature 1991, Part 2

Literature 1991, Part 2 PDF Author: Astronomisches Rechen-Institut
Publisher: Springer Science & Business Media
ISBN: 3662123762
Category : Science
Languages : en
Pages : 1592

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Book Description
"Astronomy and Astrophysics Abstracts" appearing twice a year has become oneof the fundamental publications in the fields of astronomy, astrophysics andneighbouring sciences. It is the most important English-language abstracting journal in the mentioned branches. The abstrats are classified under more than a hundred subject categories, thus permitting a quick survey of the whole extended material. The AAA is a valuable and important publication for all students and scientists working in the fields of astronomy and related sciences. As such it represents a necessary ingredient of any astronomical library all over the world.

Protostars and Planets VI

Protostars and Planets VI PDF Author: Henrik Beuther
Publisher: University of Arizona Press
ISBN: 0816531242
Category : Science
Languages : en
Pages : 945

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Book Description
Proceedings of a conference held in Heidelberg, Germany, July 15-20, 2013.

The Formation and Early Evolution of Stars

The Formation and Early Evolution of Stars PDF Author: Norbert S. Schulz
Publisher: Springer Science & Business Media
ISBN: 3642239269
Category : Science
Languages : en
Pages : 530

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Book Description
Starburst regions in nearby and distant galaxies have a profound impact on our understanding of the early universe. This new, substantially updated and extended edition of Norbert Schulz’s unique book "From Dust to Stars" describes complex physical processes involved in the creation and early evolution of stars. It illustrates how these processes reveal themselves from radio wavelengths to high energy X-rays and gamma–rays, with special reference towards high energy signatures. Several sections devoted to key analysis techniques demonstrate how modern research in this field is pursued and new chapters are introduced on massive star formation, proto-planetary disks and observations of young exoplanets. Recent advances and contemporary research on the theory of star formation are explained, as are new observations, specifically from the three great observatories of the Spitzer Space Telescope, the Hubble Space Telescope and the Chandra X-Ray Observatory which all now operate at the same time and make high resolution space based observing in its prime. As indicated by the new title two new chapters have been included on proto-planetary disks and young exoplanets. Many more colour images illustrate attractive old and new topics that have evolved in recent years. The author gives updates in theory, fragmentation, dust, and circumstellar disks and emphasizes and strengthens the targeting of graduate students and young researchers, focusing more on computational approaches in this edition.

The Physics of Star Formation and Early Stellar Evolution

The Physics of Star Formation and Early Stellar Evolution PDF Author: Charles J. Lada
Publisher: Springer Science & Business Media
ISBN: 9401136424
Category : Science
Languages : en
Pages : 779

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Book Description
The origin of stars is one of the principle mysteries of nature. During the last two decades advances in technology have enabled more progress to be made in the quest to understand stellar origins than at any other time in history. The study of star formation has developed into one of the most important branches of mod ern astrophysical research. A large body of observational data and a considerable literat ure now exist concerning this topic and a 1arge community of international astronomers and physicists devote their efforts attempting to decipher the secrets of stellar birth. Yet, the young astronomerjphysicist or more advanced researcher desiring to obtain a basic background in this area of research must sift through a very diverse and sometimes bewildering literature. A literature which includes research in many discip1ines and sub discip1ines of classical astrophysics from stel lar structure to the interstellar medium and encompasses the entire range of the electromagnetic spectrum from radio to gamma rays. Often, the reward of a suc cessfu1 foray through the current literature is the realization that the results can be obsolete and outdated as soon as the ink is dry in the journal or the conference proceeding in which they are published.

Cosmic Winds and the Heliosphere

Cosmic Winds and the Heliosphere PDF Author: J. R. Jokipii
Publisher: University of Arizona Press
ISBN: 0816538638
Category : Science
Languages : en
Pages : 1048

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Book Description
Until the advent of space physics, astrophysical plasmas could be studied only using ground-based observations. Although observational methods have advanced over recent decades, the merging of heliospheric physics with astrophysics is far from complete due to the vastly different techniques employed by astronomers and space physicists. That astrophysical plasmas can be studies directly is a major advance in astrophysical research. The solar wind from the Sun is only one of many examples of solar winds, but it provides scientists with a basis for understanding how these formerly disparate disciplines are related. Cosmic Winds and the Heliosphere is a comprehensive sourcebook on conceptually correlated topics in astrophysical winds and heliospheric physics. The contributors review the various kinds of winds, such as solar wind, winds of cataclysmic variables, and winds from pulsating stars. They then examine the physics of wind origin and physical phenomena in winds. including heliospheric shocks, magnetohydrodynamic turbulence, and kinetic phenomena. A final section considers interactions with surrounding media, with contributions ranging from studies of the interstellar cloud surrounding the solar system to considerations of solar wind interaction with comets. Prepared to the scrupulous standards of the University of Arizona Space Science Series, Cosmic Winds and the Heliosphere is an essential volume for astronomers and space physicists.

Protostars and Planets V

Protostars and Planets V PDF Author: Bo Reipurth
Publisher: University of Arizona Press
ISBN: 9780816526543
Category : Science
Languages : en
Pages : 994

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Book Description
'Protostars and Planets V' builds on the latest results from recent advances in ground and space-based astronomy and in numerical computing techniques to offer the most detailed and up-to-date picture of star and planet formation - including the formation and early evolution of our own solar system.