Download or read book Unveiling the Origin of Filamentary Structures Around Central Galaxies in Groups and Clusters written by Valeria Olivares and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The classical cooling-flow' model fails in the absence of an external non-gravitational heating mechanism needed to offset catastrophic radiative cooling in the intracluster medium (ICM) of galaxy clusters. Feedback from an active galactic nuclei (AGN) contributes to offset the cooling through bubbles inflated by radio jets launched from massive black holes. However, it cannot completely offset the cooling, as the brightest cluster galaxies (BCGs) harbors extended warm and cold gas reservoirs of gas, whose physical nature remains unknown. The aim of this thesis is to understand the life-cycle of gas in the presence of radio-mechanical AGN-feedback by studying the filamentary network surrounding nearby Brightest Cluster Galaxies and Brightest Group Galaxies (BGGs). We present 15 galaxy clusters and 18 galaxy groups to investigate the origin and physical state of these gaseous filaments. By combining ALMA, MUSE observations, and archive optical textit{Hubble Space Telescope}, X-ray textit{Chandra}, radio VLA, GMRT observations, we have assembled a comprehensive picture of these enigmatic filaments.BCGs reveal extended networks, 10--60~kpc, of Halpha filaments as a consequence of residual cooling from the hot ICM. ALMA observations show clumpy, massive, molecular filaments, preferentially located beneath the radio bubbles inflated by the AGN. The optical nebula is certainly tracing the warm envelopes of cold molecular filaments. Surprisingly, the radial profile of the Halpha/CO flux ratio is roughly constant for most of the objects, revealing that cold gas could be present in the faintest filaments detected in Halpha, and indicating that a local process must be responsible for the excitation mechanism of the gas. To investigate where the cold gas condensed out from the ICM, we compare the radial extent of the filaments with predictions from numerical simulations. We found that the filaments are always inside the low-entropy region, and where the ratio of the cooling time over the free-fall time is minimum, and similarly, where the ratio of the cooling time to the eddy-turnover time is approximately unity. This may be consistent with theoretical predictions, which argue that cold gas might condense from the cooling of the ICM via the top-down cascade through thermal instabilities. Finally, we found that the velocity of the molecular gas is below the escape velocity of the BCG, indicating that cold clouds must then fall back onto the black hole, feeding the central engine, where the cycle starts again.By extending the sample, including 18 galaxy groups, we explore an intermediate-mass range between individual galaxies and massive clusters, offering an exciting avenue to study the life-cycle of gas and the effect of AGN-feedback. Our MUSE observations reveal ionized gas distributed on principally within filamentary structures, 3--14~kpc, but massive rotating disks and rings are also identified, in comparison to galaxy clusters where the filaments are ubiquitous. The exaltation of gas appears to be dominated by LINERS; though, star-formation is identified within the clumpy rings. Spatial and kinematic information of the molecular phase is required to understand the evolutionary scenario of gas cycling entirely. Our NOEMA observations of a disk source reveal that these two temperature phases are cospatial and comoving, which might hint a common origin.Significant progress has been made in the understanding of the origin of the filamentary structures in galaxy clusters and groups by increasing the size of the sample. However, many questions remain in the inkwell. Future high-spatial and spectral resolution facilities, such as Athena satellite, will yield a more complete view of the nature of the gas.
Download or read book Unveiling Galaxies written by Jean-René Roy and published by Cambridge University Press. This book was released on 2018 with total page 311 pages. Available in PDF, EPUB and Kindle. Book excerpt: A thought provoking study of the powerful impact of images in guiding astronomers' understanding of galaxies through time.
Download or read book Unveiling Large scale Structures Behind the Milky Way written by Chantal Balkowski and published by . This book was released on 1994 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Outskirts of Galaxy Clusters IAU C195 written by International Astronomical Union. Colloquium and published by Cambridge University Press. This book was released on 2004-12-16 with total page 586 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains the proceedings of the International Astronomical Union Colloquium no. 195, held in Torino, Italy in 2004. The meeting investigated the formation of galaxies within a full cosmological context, focusing on the outer regions of galaxy clusters. The observed correlation of optical and radio properties of galaxies with their environment indicates that the formation and evolution of galaxies is intimately linked to the formation of large scale structure. With chapters written by leading authorities in the field, this timely volume investigates the role of the environment in determining the properties of galaxies. It describes the distribution of matter and galaxies on the largest scales in the Universe, the processes of cluster and galaxy formation, their role and interplay. This is a valuable collection of review articles for professional astronomers.
Download or read book Introduction to Pattern Recognition written by Sergios Theodoridis and published by Academic Press. This book was released on 2010-03-03 with total page 233 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introduction to Pattern Recognition: A Matlab Approach is an accompanying manual to Theodoridis/Koutroumbas' Pattern Recognition. It includes Matlab code of the most common methods and algorithms in the book, together with a descriptive summary and solved examples, and including real-life data sets in imaging and audio recognition. This text is designed for electronic engineering, computer science, computer engineering, biomedical engineering and applied mathematics students taking graduate courses on pattern recognition and machine learning as well as R&D engineers and university researchers in image and signal processing/analyisis, and computer vision. Matlab code and descriptive summary of the most common methods and algorithms in Theodoridis/Koutroumbas, Pattern Recognition, Fourth Edition Solved examples in Matlab, including real-life data sets in imaging and audio recognition Available separately or at a special package price with the main text (ISBN for package: 978-0-12-374491-3)
Download or read book Galaxy Formation and Evolution written by Houjun Mo and published by Cambridge University Press. This book was released on 2010-05-20 with total page 841 pages. Available in PDF, EPUB and Kindle. Book excerpt: A coherent introduction for researchers in astronomy, particle physics, and cosmology on the formation and evolution of galaxies.
Download or read book The Discovery of Cosmic Voids written by Laird A. Thompson and published by Cambridge University Press. This book was released on 2020-12-10 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: The large-scale structure of the Universe is dominated by vast voids with galaxies clustered in knots, sheets, and filaments, forming a great 'cosmic web'. In this personal account of the major astronomical developments leading to this discovery, we learn from Laird A. Thompson, a key protagonist, how the first 3D maps of galaxies were created. Using non-mathematical language, he introduces the standard model of cosmology before explaining how and why ideas about cosmic voids evolved, referencing the original maps, reproduced here. His account tells of the competing teams of observers, racing to publish their results, the theorists trying to build or update their models to explain them, and the subsequent large-scale survey efforts that continue to the present day. This is a well-documented account of the birth of a major pillar of modern cosmology, and a useful case study of the trials surrounding how this scientific discovery became accepted.
Download or read book Enrichment study of hot intra cluster gas through X ray spectroscopy written by Jelle de Plaa and published by Jelle de Plaa. This book was released on 2007 with total page 161 pages. Available in PDF, EPUB and Kindle. Book excerpt: Clusters of galaxies are the biggest objects known in the universe. They consist of large groups of hundreds of galaxies that each contain hundreds of billions of stars. The member galaxies are embedded in a cloud of hot X-ray emitting gas that spans over millions of light years. During the formation of clusters, a large fraction of the chemical elements that supernova explosions produce is ejected from the galaxies into the surrounding hot gas. In this thesis, Jelle de Plaa presents the results of his study of this chemical enrichment of the hot gas. He used observations performed by ESA's XMM-Newton X-ray observatory to measure the abundances of several elements and compared them to supernova-model yields.
Download or read book The Origin of the Galaxy and Local Group written by Joss Bland-Hawthorn and published by Springer Science & Business Media. This book was released on 2014-02-11 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the updated and expanded lecture notes of the 37th Saas-Fee Advanced Course organised by the Swiss Society for Astrophysics and Astronomy. It offers the most comprehensive and up to date review of one of the hottest research topics in astrophysics - how our Milky Way galaxy formed. Joss Bland-Hawthorn & Ken Freeman lectured on Near Field Cosmology - The Origin of the Galaxy and the Local Group. Francesca Matteucci’s chapter is on Chemical evolution of the Milky Way and its Satellites. As designed by the SSAA, books in this series – and this one too – are targeted at graduate and PhD students and young researchers in astronomy, astrophysics and cosmology. Lecturers and researchers entering the field will also benefit from the book.
Download or read book Astrophysics Of Gas Nebulae and Active Galactic Nuclei written by Donald E. Osterbrock and published by University Science Books. This book was released on 2006 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thoroughly revised and expanded throughout, the new edition is a graduate-level text and reference book on gaseous nebulae, nova and supernova remnants. Much of the new data and new images are from the Hubble Space Telescope with two wholly new chapters being added along with other new features. The previous edition which was tried and tested for thirty years has now been succeeded by a revised, updated, larger edition, which will be valuable to anyone seriously interested in astrophysics.
Download or read book Clusters of Galaxies written by John S. Mulchaey and published by Cambridge University Press. This book was released on 2010-06-10 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Clusters of galaxies are the largest and most massive collapsed systems in the Universe. In addition to containing thousands of galaxies, these systems contain large amounts of hot, X-ray-emitting gas and dark matter. This volume contains a series of review papers on this exciting and important astronomical topic by international leaders in the field. The work is appropriate as an introduction for physics and astronomy graduate students as well as a reference source for professionals.
Download or read book INIS Atomindex written by and published by . This book was released on 1988 with total page 948 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book X Ray Emission from Clusters of Galaxies written by Craig L. Sarazin and published by Cambridge University Press. This book was released on 1988-03-17 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: First published in 1988, this book is a comprehensive survey of the astrophysical characteristics of the hot gas which pervades clusters of galaxies. In our universe, clusters of galaxies are the largest organised structures. Typically they comprise hundreds of galaxies moving through a region of space ten million light years in diameter. The volume between the galaxies is filled with gas having a temperature of 100 million degrees. This material is a strong source of cosmic X-rays. Dr Sarazin describes the theoretical description of the origin, dynamics, and physical state of the cluster gas. Observations by radio and optical telescopes are also summarised. This account is addressed to professional astronomers and to graduate students. It is an exhaustive summary of a rapidly expanding field of research in modern astrophysics.
Download or read book Galactic Dynamics written by James Binney and published by Princeton University Press. This book was released on 2011-10-30 with total page 902 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since it was first published in 1987, Galactic Dynamics has become the most widely used advanced textbook on the structure and dynamics of galaxies and one of the most cited references in astrophysics. Now, in this extensively revised and updated edition, James Binney and Scott Tremaine describe the dramatic recent advances in this subject, making Galactic Dynamics the most authoritative introduction to galactic astrophysics available to advanced undergraduate students, graduate students, and researchers. Every part of the book has been thoroughly overhauled, and many sections have been completely rewritten. Many new topics are covered, including N-body simulation methods, black holes in stellar systems, linear stability and response theory, and galaxy formation in the cosmological context. Binney and Tremaine, two of the world's leading astrophysicists, use the tools of theoretical physics to describe how galaxies and other stellar systems work, succinctly and lucidly explaining theoretical principles and their applications to observational phenomena. They provide readers with an understanding of stellar dynamics at the level needed to reach the frontiers of the subject. This new edition of the classic text is the definitive introduction to the field. ? A complete revision and update of one of the most cited references in astrophysics Provides a comprehensive description of the dynamical structure and evolution of galaxies and other stellar systems Serves as both a graduate textbook and a resource for researchers Includes 20 color illustrations, 205 figures, and more than 200 problems Covers the gravitational N-body problem, hierarchical galaxy formation, galaxy mergers, dark matter, spiral structure, numerical simulations, orbits and chaos, equilibrium and stability of stellar systems, evolution of binary stars and star clusters, and much more Companion volume to Galactic Astronomy, the definitive book on the phenomenology of galaxies and star clusters
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 International Aerospace Abstracts written by and published by . This book was released on 1993 with total page 1070 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Statistics of the Galaxy Distribution written by Vicent J. Martinez and published by CRC Press. This book was released on 2001-12-20 with total page 451 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the last decade, statisticians have developed new statistical tools in the field of spatial point processes. At the same time, observational efforts have yielded a huge amount of new cosmological data to analyze. Although the main tools in astronomy for comparing theoretical results with observation are statistical, in recent years, cosmologis
