Download or read book The Circumstellar Environment of Evolved Stars as Revealed by Studies of Circumstellar Water Masers written by Kevin Marvel and published by Universal-Publishers. This book was released on 1996-12 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt: The dissertation presents the results of a multi-epoch very long baseline interferometric study of water masers located in the extended atmospheres of evolved stars. The research was performed using the Very Long Baseline Array and Very Large Array of the National Radio Astronomy Observatory. Optical monitoring of the stars was provided by the American Association of Variable Star Observers, the Variable Star Network and Dr. Bill Neely of the NF/Observatory. Water masers of found to exist in a region where a population inversion of the rotation transition of 22 GHz can be maintained by collisional pumping. The masers are identified as individual pockets of gas, which have the good velocity coherence and may be imaged using radio interferometry. Stellar winds are initiated in these sources by dust formation and acceleration of the gas through momentum coupling. The typical wind speeds in the region of the water masers are 10 to 20 km/s The water masers are followed through several epochs of observation and exhibit proper motions consistent with the assumed source distance and the measured outflow of velocity in the water maser region. Estimates of the distance to the sources using statistical approximation are in agreement with the currently accepted distances to the stars. A detailed kinematic model is used to describe the flow motions of the gas in the maser region. The regions are found to be complex and not well modeled by uniform radial outflow, radial outflow with rotation, or radial with acceleration. The reasons for this are explored and include anisotropic velocity fields induced through non-uniform dust formations near the star and incomplete sampling of the outflow due to a lack of detected masers. Possibilities for future work in the subject are described and include more sophisticated modeling, more sensitive observations, and analysis of other maser species.
Download or read book Infrared Interferometry and Spectroscopy of Circumstellar Envelopes written by John David Monnier and published by . This book was released on 1999 with total page 608 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Astronomy Reports written by and published by . This book was released on 1999 with total page 462 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Referativny zhurnal written by and published by . This book was released on 1999 with total page 600 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Luminous Stars in Nearby Galaxies written by Roberta M. Humphreys and published by MDPI. This book was released on 2020-12-10 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: Studies on the populations of luminous stars in nearby resolved galaxies have revealed a complex distribution in the luminosity–temperature plane (the HR diagram). The fundamentals of massive star evolution are mostly understood, but the roles of mass loss, episodic mass loss, rotation, and binarity are still in question. Moreover, the final stages of these stars of different masses and their possible relation to each other are not understood. The purpose of this volume is to provide a current review of the different populations of evolved massive stars. The emphasis is on massive stars in the Local Group, the Magellanic Clouds, and the nearby spirals M31 and M33.
Download or read book Literature 1988 Part 2 written by Astronomisches Rechen-Institut and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 1308 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the reviews: "Astronomy and Astrophysics Abstracts has appeared in semi-annual volumes since 1969 and it has already become one of the fundamental publications in the fields of astronomy, astrophysics and neighbouring sciences. It is the most important English-language abstracting journal in the mentioned branches. ...The abstracts 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." Space Science Reviews#1 "Dividing the whole field plus related subjects into 108 categories, each work is numbered and most are accompanied by brief abstracts. Fairly comprehensive cross-referencing links relevant papers to more than one category, and exhaustive author and subject indices are to be found at the back, making the catalogues easy to use. The series appears to be so complete in its coverage and always less than a year out of date that I shall certainly have to make a little more space on those shelves for future volumes." The Observatory Magazine#2
Download or read book Literature 1988 Part 1 written by U. Esser and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 1266 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the reviews: "Astronomy and Astrophysics Abstracts has appeared in semi-annual volumes since 1969 and it has already become one of the fundamental publications in the fields of astronomy, astrophysics and neighbouring sciences. It is the most important English-language abstracting journal in the mentioned branches. ...The abstracts 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." Space Science Reviews#1 "Dividing the whole field plus related subjects into 108 categories, each work is numbered and most are accompanied by brief abstracts. Fairly comprehensive cross-referencing links relevant papers to more than one category, and exhaustive author and subject indices are to be found at the back, making the catalogues easy to use. The series appears to be so complete in its coverage and always less than a year out of date that I shall certainly have to make a little more space on those shelves for future volumes." The Observatory Magazine#2
Download or read book Environmental Research Papers written by and published by . This book was released on 1988 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Astrophysical Masers IAU S336 written by International Astronomical Union. Symposium and published by Cambridge University Press. This book was released on 2018-09-13 with total page 481 pages. Available in PDF, EPUB and Kindle. Book excerpt: Summarizes state of the art observations and theories pertaining to astrophysical masers and their environments, for graduate students and researchers.
Download or read book Circumstellar Habitable Zones written by Laurance Reeve Doyle and published by . This book was released on 1996 with total page 556 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Highlights of Astronomy written by Jacqueline Bergeron and published by Springer Science & Business Media. This book was released on 2013-12-01 with total page 689 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since 1967. the most prominent events of a General Assembly of the International Astronomical Union are published in a separate volume. The Highlights of Astronomy (volume 9) report on the major scientific presentations made at the XXIst General Assembly July 23-August 1. 1991. Buenos Aires. Argentina. The present volume contains the texts of the three invited Di scourses and of the papers presented duri ng seven Joi nt Discussion Meetings and eight Joint Commission Meetings. The invited Discourses were arranged by the IAU Executive Committee and the Joint Discourses and Commission Meetings by the respective chairpersons. The overall responsability of the General Assembly was carried out by the IAU General Secretary (19B8-1991). Dr. D. McNally. I am indebted to the authors of the invited Di scourses. to the organi zers and editors of the scientific sessions for having provided me with all the material for publication in due time. I want to particularly acknowledge the case with which Dr. J.H. Hughes. who unfortunately died a few days ago from cancer. prepared and checked unti 1 the 1 ast few weeks the report on the new IAU Reference System. This report itself concludes long and difficult discussions among IAU members that he led in a wise and clear sighted manner.
Download or read book Astronomy and Astrophysics Abstracts written by S. Böhme and published by Springer Science & Business Media. This book was released on 2013-12-14 with total page 1180 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the reviews: Astronomy and Astrophysics Abstracts has appeared in semi-annual volumes since 1969 and it has already become one of the fundamental publications in the fields of astronomy, astrophysics and neighbouring sciences. It is the most important English-language abstracting journal in the mentioned branches. ... The abstracts are classified under more than 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." Space Science Reviews #1 "Dividing the whole field plus related subjects into 108 categories, each work is numbered and most are accompanied by brief abstracts. Fairly comprehensive cross-referencing links relevant papers to more than one category, and exhaustive author and subject indices are to be found at the back, making the catalogues easy to use. The series appears to be so complete in its coverage and always less than a year out of date that I shall certainly have to make a little more space on those shelves for future volumes." The Observatory Magazine #1
Download or read book Literature 1997 Part 1 written by Astronomisches Rechen-InstitutARI and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 1746 pages. Available in PDF, EPUB and Kindle. Book excerpt: Astronomy and Astrophysics Abstracts is devoted to the recording, summarizing and indexing of astronomical publications throughout the world. Two volumes are scheduled to appear per year. Volume 67 records 10,903 papers covering besides the classical fields of astronomy and astrophysics such matters as space flights related to astronomy, lunar and planetary probes and satellites, meteorites and interplanetary matter, X rays and cosmic rays, quasars and pulsars. The abstracts are classified under more than one hundred subject categories thus permitting quick surveying of the bulk of material published on the same topic within six months. For instance, this volume records 119 papers on minor planets, 155 papers on supernovae, and 554 papers on cosmology.
Download or read book The Irish Astronomical Journal written by and published by . This book was released on 1998 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Physics Briefs written by and published by . This book was released on 1994 with total page 916 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Literature 1989 Part 1 written by Astronomisches Rechen-Institut and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 1433 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the reviews: "Astronomy and Astrophysics Abstracts has appeared in semi-annual volumes since 1969 and it has already become one of the fundemental publications in the fields of astronomy, astrophysics and neighbouring sciences. It is the most important English-language abstracting journal in the mentioned branches. ...The abstracts 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." Space Science Review# "Dividing the whole field plus related subjects into 108 categories, each work is numbered and most are accompanied by brief abstracts. Fairly comprehensive cross-referencing links relevant papers to more than one category, and exhaustive author and subject indices are to be found at the back, making the catalogues easy to use. The series appears to be so complete in its coverage and always less than a year out of date that I shall certainly have to make a little more space on those shelves for future volumes." The Observatory Magazine#
Download or read book Interstellar Molecules written by Koichi M. T. Yamada and published by Springer Science & Business Media. This book was released on 2011-04-07 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book deals with the astrophysics and spectroscopy of the interstellar molecules. In the introduction, overview and history of interstellar observations are described in order to help understanding how the modern astrophysics and molecular spectroscopy have been developed interactively. The recent progress in the study of this field is briefly summarized. Furthermore, the basic knowledge of molecular spectroscopy, which is essential to correctly comprehend the astrophysical observations, is presented in a compact form.
