Download or read book Introduction to Brown Dwarfs written by John Gizis and published by AAS-IOP Astronomy. This book was released on 2022-12-15 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book 50 Years of Brown Dwarfs written by Viki Joergens and published by Springer Science & Business Media. This book was released on 2013-11-27 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: The years 2012/2013 mark the 50th anniversary of the theoretical prediction that Brown Dwarfs, i.e. degenerate objects which are just not massive enough to sustain stable hydrogen fusion, exist. Some 20 years after their discovery, how Brown Dwarfs form is still one of the main open questions in the theory of star formation. In this volume, the pioneers of Brown Dwarf research review the history of the theoretical prediction and the subsequent discovery of Brown Dwarfs. After an introduction, written by Viki Joergens, reviewing Shiv Kumar's theoretical prediction of the existence of brown dwarfs, Takenori Nakano reviews his and Hayashi's calculation of the Hydrogen Burning Minimum Mass. Both predictions happened in the early 1960s. Jill Tarter then writes on the introduction of the term 'Brown Dwarf', before Ben Oppenheimer, Rafael Rebolo and Gibor Basri describe their first discovery of Brown Dwarfs in the 1990s. Lastly, Michael Cushing and Isabelle Baraffe describe the development of the field to the current state of the art. While the book is mainly aimed at the Brown Dwarf research community, the description of the pioneering period in a scientific field will attract general readers interested in astronomy as well.
Download or read book An Introduction to Brown Dwarfs Failed Stars and Super Jupiters written by John Gizis and published by . This book was released on 2024-11-15 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Very Low Mass Stars and Brown Dwarfs written by Rafael Rebolo and published by Cambridge University Press. This book was released on 2000-11-27 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume provides a state-of-the-art review of our current knowledge of brown dwarfs and very low-mass stars. The hunt for and study of these elusive objects is currently one of the most dynamic areas of research in astronomy for two reasons. Brown dwarfs bridge the gap between stars and planets, and they may constitute an important part of the 'dark matter' of the Universe. This volume presents review articles from a team of international authorities who gathered at a conference in La Palma to assess the spectacular progress that has been made in this field in the last few years.
Download or read book New Light on Dark Stars written by Neill I. Reid and published by Springer Science & Business Media. This book was released on 2013-11-27 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt: Perhaps the most common question that a child asks when he or she sees the night sky from a dark site for the first time is: 'How many stars are there?' This happens to be a question which has exercised the intellectual skills of many astronomers over the course of most of the last century, including, for the last two decades, one of the authors of this text. Until recently, the most accurate answer was 'We are not certain, but there is a good chance that almost all of them are M dwarfs. ' Within the last three years, results from new sky-surveys - particularly the first deep surveys at near infrared wavelengths - have provided a breakthrough in this subject, solidifying our census of the lowest-mass stars and identifying large numbers of the hitherto almost mythical substellar-mass brown dwarfs. These extremely low-luminosity objects are the central subjects of this book, and the subtitle should be interpreted accordingly. The expression 'low-mass stars' carries a wide range of meanings in the astronomical literature, but is most frequently taken to refer to objects with masses comparable with that of the Sun - F and G dwarfs, and their red giant descendants. While this definition is eminently reasonable for the average extragalactic astronomer, our discussion centres on M dwarfs, with masses of no more than 60% that of the Sun, and extends to 'failed stars' - objects with insufficient mass to ignite central hydrogen fusion.
Download or read book The Physics of Low Mass Stars Brown Dwarfs and Gaseous Planets written by Gilles Chabrier and published by World Scientific Publishing Company. This book was released on 2014-12-31 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a complete introduction and overview to the rapidly expanding field of extrasolar planets and brown dwarfs. The following topics are covered: observational techniques, surveys, studies of individual objects, theoretical properties of low-mass stars, brown dwarfs and giant planets, the contribution of these objects to the Galactic mass-budget, processes that lead to formation of planets versus white dwarfs, implication of such objects for the occurrence of Earth-like planets, and future prospects in the field. The book enables readers to gain a solid scientific background in all the essential aspects of this exciting new area of astronomical research.
Download or read book Brown Dwarf Companions to Young Solar an written by Stanimir Metchev and published by Universal-Publishers. This book was released on 2006-02 with total page 255 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present results from an adaptive optics survey conducted with the Palomar and Keck telescopes over 3 years, which measured the frequency of stellar and sub-stellar companions to Sun-like stars. The survey sample contains 266 stars in the 3-10000 million year age range at heliocentric distances between 8 and 200 parsecs and with spectral types between F5-K5. A sub-sample of 101 stars, between 3-500 million years old, were observed in deep exposures with a coronagraph to search for faint sub-stellar companions. A total of 288 candidate companions were discovered around the sample stars, which were re-imaged at subsequent epochs to determine physical association with the candidate host stars by checking for common proper motion. Benefitting from a highly accurate astrometric calibration of the observations, we were able to successfully apply the common proper motion test in the majority of the cases, including stars with proper motions as small as 20 milli-arcseconds/year. The results from the survey include the discovery of three new brown dwarf companions (HD 49197B, HD 203030B, and ScoPMS 214B), 43 new stellar binaries, and a triple system. The physical association of an additional, a priori-suspected, candidate sub-stellar companion to the star HII 1348 is astrometrically confirmed. The newly-discovered and confirmed young brown dwarf companions span a range of spectral types between M5 and T0.5, and will be of prime significance for constraining evolutionary models of young brown dwarfs and extra-solar planets. Based on the 3 new detections of sub-stellar companions in the 101 star sub-sample and following a careful estimate of the survey incompleteness, a Bayesian statistical analysis shows that the frequency of 0.012-0.072 solar-mass brown dwarfs in 30-1600 AU orbits around young solar analogs is 6.8% (-4.9%, +8.3%; 2-sigma limits). While this is a factor of 3 lower than the frequency of stellar companions to G-dwarfs in the same orbital range, it is significantly higher than the frequency of brown dwarfs in 0-3 AU orbits discovered through precision radial velocity surveys. It is also fully consistent with the observed frequency of 0-3 AU extra-solar planets. Thus, the result demonstrates that the radial-velocity "brown dwarf desert" does not extend to wide separations, contrary to previous belief.
Download or read book Ultracool Dwarfs written by Hugh R.A. Jones and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 199 pages. Available in PDF, EPUB and Kindle. Book excerpt: Once you have looked at the night sky on a moonless night it is not hard to realise why so much of our science and religion has its roots in the stars. Yet it took until 1850 to realise that fainter stars were not necessarily further away, nor the brighter ones closer. In fact within the magnitude range observable to the naked eye it is probable that the brighter star is in fact further away. Even today the measurement of stellar distances is relatively difficult and is gener ally only done using dedicated telescopes. In the early years of the 20th century Hertzsprung and Russell developed a powerful classification diagram which al lows stars to be distinguished using a plot of their colour versus magnitude. The construction of this diagram involved the use of spectroscopy which has become the cornerstone of modern astronomy. As telescopes become more powerful, de tectors more sensitive and more physics is added to astrophysics, astronomical spectroscopy becomes a more powerful tool. The concern of this book is the spectral classification of stars. With a single spectrum of a star it is possible to uniquely classify an object and find its place on the Hertzsprung-Russell diagram. This spectrum is thus equivalent to having the colour and the magnitude of the object which can in turn be related to mass and other quantities.
Download or read book Evolution of Brown Dwarfs written by Sen-Ben R. Liao and published by . This book was released on 1989 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book New Light on Dark Stars written by Neil Reid and published by Springer. This book was released on 2009-09-02 with total page 560 pages. Available in PDF, EPUB and Kindle. Book excerpt: There has been very considerable progress in research into low-mass stars, brown dwarfs and extrasolar planets during the past few years, particularly since the fist edtion of this book was published in 2000. In this new edtion the authors present a comprehensive review of both the astrophysical nature of individual red dwarf and brown dwarf stars and their collective statistical properties as an important Galactic stellar population. Chapters dealing with the observational properies of low-mass dwarfs, the stellar mass function and extrasolar planets have been completely revised. Other chapters have been significantly revised and updated as appropriate, including important new material on observational techniques, stellar acivity, the Galactic halo and field star surveys. The authors detail the many discoveries of new brown dwarfs and extrasolar planets made since publication of the first edition of the book and provide a state-of-the-art review of our current knowledge of very low-mass stars, brown dwarfs and extrasolar planets, including both the latest observational results and theoretical work.
Download or read book AN INTRODUCTION TO ASTROPHYSICS written by BAIDYANATH BASU and published by PHI Learning Pvt. Ltd.. This book was released on 2010-01-01 with total page 599 pages. Available in PDF, EPUB and Kindle. Book excerpt: This invaluable book, now in its second edition, covers a wide range of topics appropriate for both undergraduate and postgraduate courses in astrophysics. The book conveys a deep and coherent understanding of the stellar phenomena, and basic astrophysics of stars, galaxies, clusters of galaxies and other heavenly bodies of interest. Since the first appearance of the book in 1997, significant progress has been made in different branches of Astronomy and Astrophysics. The second edition takes into account the developments of the subject which have taken place in the last decade. It discusses the latest introduction of L and T dwarfs in the Hertzsprung-Russel diagram (or H-R diagram). Other developments discussed pertain to standard solar model, solar neutrino puzzle, cosmic microwave background radiation, Drake equation, dwarf galaxies, ultra compact dwarf galaxies, compact groups and cluster of galaxies. Problems at the end of each chapter motivate the students to go deeper into the topics. Suggested readings at the end of each chapter have been complemented.
Download or read book New Light on Dark Stars written by I. Neill Reid and published by . This book was released on 2000 with total page 470 pages. Available in PDF, EPUB and Kindle. Book excerpt: Perhaps the most common question that a child asks when he or she sees the night sky from a dark site for the first time is: 'How many stars are there?' This happens to be a question which has exercised the intellectual skills of many astronomers over the course of most of the last century, including, for the last two decades, one of the authors of this text. Until recently, the most accurate answer was 'We are not certain, but there is a good chance that almost all of them are M dwarfs. ' Within the last three years, results from new sky-surveys - particularly the first deep surveys at near infrared wavelengths - have provided a breakthrough in this subject, solidifying our census of the lowest-mass stars and identifying large numbers of the hitherto almost mythical substellar-mass brown dwarfs. These extremely low-luminosity objects are the central subjects of this book, and the subtitle should be interpreted accordingly. The expression 'low-mass stars' carries a wide range of meanings in the astronomical literature, but is most frequently taken to refer to objects with masses comparable with that of the Sun - F and G dwarfs, and their red giant descendants. While this definition is eminently reasonable for the average extragalactic astronomer, our discussion centres on M dwarfs, with masses of no more than 60% that of the Sun, and extends to 'failed stars' - objects with insufficient mass to ignite central hydrogen fusion.
Download or read book Our Neighbor Stars written by Thomas Wm Hamilton and published by Strategic Book Publishing. This book was released on 2012-02 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The sky's the limit in the fascinating book Our Neighbor Stars: Including Brown Dwarfs. The book presents all known information on the 100 stars nearest Earth, as well as the brown dwarfs within the range covered by these stars. Learn where (and whether) the stars are visible in the sky, who discovered them and how they were discovered. Read all about the stars' sizes, colors, presence of any planets, and the constellations where the stars are located. All the information is indexed, so particular types of stars can be easily found. About the Author: Thomas Wm. Hamilton has wanted to work in astronomy since he was five years old. Now retired, he taught astronomy for 32 years, and has worked for the Apollo program and in the planetarium field. His last book was Useful Star Names and his next is an anthology featuring his science fiction stories. The author grew up in San Francisco and now resides on Staten Island, New York. Publisher's Website: http: //sbpra.com/ThomasWmHamilton
Download or read book Brown Dwarfs and Extrasolar Planets written by R. Rebolo and published by . This book was released on 1998 with total page 608 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of a March 1997 workshop, with theoretical and observational papers in sections on free floating brown dwarfs, substellar objects as companions to stars, atmospheres and interiors, and the mass function. Subjects include rotation of field M dwarfs, the formation of eccentric superplanets, extrasolar comets in young stellar systems, extrasolar giant planets, spectroscopic properties of ultra-cool dwarfs and brown dwarfs, the stellar mass function, and the mass of the Pleiades. Annotation copyrighted by Book News, Inc., Portland, OR
Download or read book Brown Dwarfs and UKIDSS written by David Edwin Alexander Baker and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis I present the work of two studies into the population of low-mass stars and brown dwarfs within the open galactic clusters of Praesepe and Blanco 1 using optical and infrared photometry. Observing these objects within clusters is of great importance as their known ages and distances allow for comparisons to be made between the observed results and those predicted from theoretical formation and evolutionary models, whilst expanding our understanding of the initial mass function. Following an introduction to the formation, evolution and observational history of brown dwarfs in Chapter 2 an overview of the principle data reduction processes and instruments used in this thesis is given in Chapter 3. Chapter 4 presents the result of the survey carried out in Praesepe using archival 2MASS, SDSS and UKIDSS data in a range of filters. Proper motion information is combined with colour magnitude cuts to select out and classify objects that are considered to be cluster members. Over 280 members have been identified with a cluster mass function that is consistent with the values presented for other clusters found. This mass function is in disagreement with previous values found for Praesepe. Chapter 5 presents the results of a follow up J band survey using WFCAM to theCFHT12k I and z survey of Moraux et al. (2007). The data reduction and membership selection procedure are discussed with 27 low-mass objects found to be members. Chapter 6 in contrast to the previous chapters presents a study not of brown dwarfs but of a suspected main-sequence, magnetic white-dwarf binary system found during an archival search of the UKIDSS DR3 database for objects with unusual Y band colours. The evidence for this system being a Polar is presented along with a discussion as to the assumed system properties. Follow up observations using the IAC-80 telescope, UKIRT and the SWIFT satellite are also presented. Finally in Chapter 7 I summarise the results from each chapter and identify areas of future work.
Download or read book Brown Dwarfs written by International Astronomical Union. Symposium and published by Astronomical Society of the Pacific. This book was released on 2003 with total page 608 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Introduction to Star Formation written by Derek Ward-Thompson and published by Cambridge University Press. This book was released on 2011-02-10 with total page 229 pages. Available in PDF, EPUB and Kindle. Book excerpt: Guiding the reader through all the stages that lead to the formation of a star such as our Sun, this advanced textbook provides students with a complete overview of star formation. It examines the underlying physical processes that govern the evolution from a molecular cloud core to a main-sequence star, and focuses on the formation of solar-mass stars. Each chapter combines theory and observation, helping readers to connect with and understand the theory behind star formation. Beginning with an explanation of the interstellar medium and molecular clouds as sites of star formation, subsequent chapters address the building of typical stars and the formation of high-mass stars, concluding with a discussion of the by-products and consequences of star formation. This is a unique, self-contained text with sufficient background information for self-study, and is ideal for students and professional researchers alike.
