Download or read book Morphological Evolution of Galaxies Over the Last 8 Billion Years written by Maurilio Pannella and published by . This book was released on 2007 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dynamical Evolution of Galaxies written by Xiaolei Zhang and published by Walter de Gruyter GmbH & Co KG. This book was released on 2017-12-04 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt: This research monograph presents a new dynamical framework for the study of secular morphological evolution of galaxies along the Hubble sequence. Classical approaches based on Boltzmann’s kinetic equation, as well as on its moment-equation descendants the Euler and Navier-Stokes fluid equations, are inadequate for treating the maintenance and long-term evolution of systems containing self-organized structures such as galactic density-wave modes. A global and synthetic approach, incorporating correlated fluctuations of the constituent particles during a nonequilibrium phase transition, is adopted to supplement the continuum treatment. The cutting-edge research combining analytical, N-body simulational, and observational aspects, as well as the fundamental-physics connections it provides, make this work a valuable reference for researchers and graduate students in astronomy, astrophysics, cosmology, many-body physics, complexity theory, and other related fields. Contents Dynamical Drivers of Galaxy Evolution N-Body Simulations of Galaxy Evolution Astrophysical Implications of the Dynamical Theory Putting It All Together Concluding Remarks Appendix: Relation to Kinetics and Fluid Mechanics
Download or read book The Morphological Evolution of Galaxies in Distant Clusters written by Amy Josephine Barger and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Cosmic Evolution of Galaxy Structure written by Christopher J. Conselice and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Galaxies are the fundamental units of cosmic matter that make up the universe and they change in remarkable ways over 13.7 billion years of cosmic time. We are just now discovering how galaxies we can see over these billions of years are evolving from small, star forming systems to larger, more massive and passive systems at later times. This book explains the structural evolution of galaxies, how we measure it, how these measurements change with time, and how observing this reveals important information about galaxy formation and evolution. It also explains the future of the field through the use of machine learning tools, and how galaxy structure can be used as a new approach to measure unique features of the universe, such as cosmological properties and parameters.
Download or read book Morphology Kinematics and Star Formation Across the Hubble Sequence of Galaxies written by Santiago Erroz-Ferrer and published by Springer. This book was released on 2015-11-21 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis discusses the evolution of galaxies through the study of the morphology, kinematics, and star formation properties of a sample of nearby galaxies. The main body of the thesis describes the kinematic observations with the GHaFAS Fabry-Perot instrument on the William Herschel Telescope of a sample of 29 spiral galaxies. The work is closely related to the Spitzer Survey of Stellar Structure in Galaxies, and uses the mid-infrared data of that survey to determine key parameters of the galaxies studied. From these data, important results are obtained on streaming and other non-circular motions in galaxies, on the distribution and rates of star formation, and on how correlations of these parameters and of the rotation curve shape with basic galaxy parameters yield clues on the evolutionary processes taking place in disk galaxies.
Download or read book Chemical Evolution of Galaxies written by Francesca Matteucci and published by Springer Science & Business Media. This book was released on 2012-01-05 with total page 237 pages. Available in PDF, EPUB and Kindle. Book excerpt: The term “chemical evolution of galaxies” refers to the evolution of abundances of chemical species in galaxies, which is due to nuclear processes occurring in stars and to gas flows into and out of galaxies. This book deals with the chemical evolution of galaxies of all morphological types (ellipticals, spirals and irregulars) and stresses the importance of the star formation histories in determining the properties of stellar populations in different galaxies. The topic is approached in a didactical and logical manner via galaxy evolution models which are compared with observational results obtained in the last two decades: The reader is given an introduction to the concept of chemical abundances and learns about the main stellar populations in our Galaxy as well as about the classification of galaxy types and their main observables. In the core of the book, the construction and solution of chemical evolution models are discussed in detail, followed by descriptions and interpretations of observations of the chemical evolution of the Milky Way, spheroidal galaxies, irregular galaxies and of cosmic chemical evolution. The aim of this book is to provide an introduction to students as well as to amend our present ideas in research; the book also summarizes the efforts made by authors in the past several years in order to further future research in the field.
Download or read book Star forming Galaxies Growing Up Over the Last Ten Billion Years written by Amanda Elaine Bauer and published by . This book was released on 2008 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: The work presented in this thesis investigates the evolution of starforming galaxies over the last ten billion years. This time period encompasses nearly three-fourths of the age of the Universe, when a substantial fraction of the total stellar mass forms, and the sites of active star formation shift to lower-mass galaxies. The first study presented here combines galaxies from the spectroscopic datasets of the FORS Deep Field and the MUNICS Survey and provides the first significant investigation of the specific star formation rate (SSFR; star formation rate [SFR] per unit stellar mass) over a wide range of stellar masses and redshifts (reaching redshift z = 1:5). From [OII]-derived SFRs, we find that low-mass galaxies have higher SSFRs all the way to z = 1:5, implying that star formation contributes progressively more to the growth of stellar mass in low-mass galaxies than in high-mass galaxies. In the follow-up to this study, we combine several near-infrared-selected samples to create one of the largest collections of galaxies with spectroscopic redshifts and morphologies from Hubble Space Telescope images, to characterize the stellar mass build up in galaxies since z = 1:6. The primary data comes from the FORS Deep Field, the MUNICS Survey, the GOODS-South field as observed by the K20 survey and ESO, and the Sloan Digital Sky Survey as a local comparison sample. After bringing together extensive photometric and spectroscopic data sets from several publicly available surveys, we use identical methods to derive physical properties and investigate how galaxy populations evolve with time. Galaxy properties include stellar masses derived from multiwavelength photometry, star formation rates calculated from [OII][lambda]3726Å emission lines, metallicity, color, and SSFRs. We find that the reddest, yet actively star-forming, disk-dominated galaxy population present at z ~ 1:3, decreases in number by z ~ 0:3 during the same timeframe when the bluest quiescent, disk-dominated galaxy population increases in number. We confirm the previously identified morphological separation in the SSFR versus M[subscript asterisk] plane found for local samples and for galaxies at z = 0:7: bulge-dominated galaxies are more massive and have lower SSFRs. We extend this relation for the first time to z = 1:6, showing that galaxies with high SSFRs and diskdominated structures tend to shift to lower masses as redshift decreases. We identify an observed upper envelop in SSFR that lies roughly parallel to lines of constant SFR, decreases with time, and is unaffected by incompleteness among the samples. We apply common star formation histories (constant, ex ponential, and power law) to understand the evolving populations we see, but cannot simultaneously reproduce low-mass galaxies with high SSFRs and highmass galaxies with low SSFRs at all redshifts and over our full mass range. Current semi-analytic models attempt to understand the mass at which galaxies stop forming stars through connections to Active Galactic Nuclei feedback, gas consumption, declining galaxy merger rates and/or changes in the incoming cold gas supply, but none can explain the gradual and constant decline of star formation consistent among all galaxies below this mass. We suggest a possible resolution where star formation histories of galaxies are dependent on morphology, in addition to the growing evidence for lower mass galaxies to begin forming stars at later times, and with lower initial SFRs than the initial SFRs experienced at earlier times by higher mass galaxies.
Download or read book Galaxy Formation and Evolution written by Hyron Spinrad and published by Springer Science & Business Media. This book was released on 2006-08-29 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: An Astronomical Life – Observing the Depths of the Universe” Though science as a subject can be di?cult, what has been more important for me is that its practice can also be rewarding fun! This book is crafted to expose the reader to the excitement of modern observational cosmology through the study of galaxy evolution over space and cosmic time. Recent extragalactic research has led to many rapid advances in the ?eld. Even a suitable skeptic of certain pronouncements about the age and structure of the Universe should be pleased with the large steps that have been taken in furthering our understanding of the Universe since the early 1990’s. My personal involvement in galaxy research goes back to the 1960’s. At that point, galaxies were easily recognized and partially understood as organized c- lections of stars and gas. What their masses were presented a problem, which I supposed would just fade away. But fade it didn’t. Distant active nuclei and quasars were discovered in the mid-1960’s. A c- mon view of QSOs was that they have large redshifts, but what use are they for cosmology or normal galaxy astrophysics? I shared that conclusion. My expec- tions fell below their potential utility. In short, the Universe of our expectations rarely matches the Universe as it is discovered.
Download or read book Toward a New Millennium in Galaxy Morphology written by David L. Block and published by Springer. This book was released on 2011-09-30 with total page 821 pages. Available in PDF, EPUB and Kindle. Book excerpt: South Africa - a land of paradigm shifts. A land where we are willing to leave behind the old, to bravely accept the new. What do we need to exit the dark ages in the morphology of galaxies? How prevalent is the cherishing of old concepts? Traditional morphology has been `mask-oriented', focusing on masks of dust and gas which may constitute only 5 percent of the dynamical mass of a galaxy. Some of the world's foremost astronomers flew to South Africa to address morphologically related issues at an International Conference, the proceedings of which are contained in this volume. Examine predicted extinction curves for primordial dust at high redshift. Stars evolve; why not dust? Read about the breakdown of the Hubble sequence at a redshift of one. Explore the morphology of rings; the mysteries of metal-rich globular clusters; vigorous star-formation in the Large Magellanic Cloud; the world of secular evolution, where galaxies change their shapes within one Hubble time. And much more. Examine a new kinematical classification scheme of the unmasked, dust-penetrated near-infrared images of spiral galaxies. This volume contains over 80 refereed contributions (including 18 in-depth keynote review articles), 40 pages of questions and answers, a panel discussion transcribed from tape and 24 colour plates. The volume is unique in that contributions from both high and low redshift experts are represented at a level readily accessible to postdoctoral students entering the exciting world of morphology - whether it be of the local, or more distant, Universe.
Download or read book The Evolution of Galaxies written by José M. Vilchez and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 556 pages. Available in PDF, EPUB and Kindle. Book excerpt: Galaxies have a history. This has become clear from recent sky surveys showing that distant galaxies, formed early in the life of the Universe, differ from the nearby ones. This book contains the proceedings of a 2000 conference addressing observational clues in this area.
Download or read book The Evolution of the Hubble Sequence written by Rodney Delgado Serrano and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main objective of my thesis was to provide us, for the first time, with a reliable wiev of the distant Hubble sequence, and its evolution over the past 6 Gyr. To achieve this goal, we have created a new morphological classification method which (1) includes all the available observational data, (2) can be easily reproduced, and (3) presents a negligible subjectivity. This method allows us to study homogeneously the morphology of local and distant galaxies, and has the main advantage of presenting a good correlation between the morphological type and dynamical state of each galaxy. The first step has been to study the evolution of galaxies using the IMAGES survey. This survey allowed us to establish the kinematic state of distant galaxies, to study the chemical evolution of galaxies over the past 8 Gyr, and to test important dynamical relations such as the Tully-Fisher relation. The information gained from kinematics is, indeed, crucial to guarantee a robust understanding of the different physical processes leading to the present day Hubble sequence. Using Integral Field Spectroscopy, which provides a complete kinematic diagnosis, we have been able to test our new morphological classification against the kinematic state of each galaxy. We found that the morpho-kinematic correlation is much better using our classification than other morphological classifications. Applying our classification to a representative sample of galaxies at z ∼ 0.6, we found that 4/5 of spiral galaxies are rotating disks, while more than 4/5 peculiar galaxies are not in a dynamical equilibrium. Appliyng our morphological classifications to a repesentative sample of both local and distant galaxies, having equivalent observational data, we obtained a Hubble sequence both in the local and distant Universe. We found that spiral galaxies were 5/2 times less adundant in the past, which is compensated exactly by the strong decrease by a factor 5 of peculiar galaxies, while the fractional number of elliptical and lenticular galaxies remains constant. It strongly suggests that more than half of the present-day spirals had peliculiar morphologies, 6 Gyr ago. Finally, I present further studies concerning the history of individual galaxies at z
Download or read book On the Evolution of Galaxy Protoclusters from the Epoch of Reionization to Cosmic Noon written by Jaclyn Bradli Champagne and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the last 7–8 billion years, mature galaxy clusters, characterized by massive quiescent galaxy populations residing in > 1014 M [subscript ☉] dark matter halos, have become ubiquitous features of the cosmic web. It is theorized that these clusters are preceded by a proto-cluster stage, which form at much earlier times in filamentary dark matter overdensities and later collapse into a central dark matter halo. Identifying and characterizing protoclusters between the epoch of reionization and cosmic noon, during which time they are expected to undergo periods of rapid star formation and evolution prior to gravitational collapse, remains in its nascent stages. With a heterogeneous mix of selection techniques, spectroscopic completeness, area coverage, and wavelength coverage, we are still vitally lacking a statistically complete catalog of protoclusters — and even more so a general understanding of their physical properties. This doctoral thesis addresses these questions twofold by: 1) using z ∼ 6 quasars as tracers of overdensities at multiple wavelengths, and 2) presenting a comprehensive X-ray to radio case study of a massive protocluster at z = 2.5. The first half of this thesis focuses on understanding the environments of the brightest quasars at z > 6, under the hypothesis that quasars hosting > 109 M [subscript ☉] black holes signal regions of accelerated growth and mass buildup in the early Universe. In two separate studies, I present the results of searches for enhanced star formation in the vicinities of quasars, using two complementary tracers of star–forming galaxies. Using data from the Atacama Large Millimeter Array, I show that a search for extreme dust–obscured galaxies via millimeter continuum emission yields inconclusive results concerning our ability to detect a true overdensity signal. Using the Hubble Space Telescope to search for the more abundant and less massive population of Lyman break galaxies, I show a heterogeneity of overdensity signals near these quasars. The second half of this thesis focuses on multiwavelength observations of known protoclusters at lower redshifts, where more observational tools are available to constrain their environments. I present an analysis of the member galaxies within a structurally complex protocluster core at z = 2.5 located in the COSMOS extragalactic field, using data from the Atacama Large Millimeter Array, the Very Large Array, and the COSMOS archive. I evaluate possible evolutionary hypotheses on the basis of the morphology of the cold gas needed for future star formation, the spatial distribution of its member galaxies, and the existence of a marginal X-ray detection that all present a challenge to our cosmological understanding of virial collapse of clusters during this epoch. Finally, I present a future outlook on further case studies and large surveys which will be made possible by next generation facilities
Download or read book The Orbital and Morphological Evolution of Dwarf Galaxies in the Local Group written by Lucio Mayer (astronomo.) and published by . This book was released on 2000 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Evolution of Stellar Mass and Morphology in the Last 11 Billion Years written by Alice Mortlock and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Secular Evolution of Galaxies written by Jesús Falcón-Barroso and published by Cambridge University Press. This book was released on 2012 with total page 657 pages. Available in PDF, EPUB and Kindle. Book excerpt: The formation and evolution of galaxies is one of the most important topics in modern astrophysics. Secular evolution refers to the relatively slow dynamical evolution due to internal processes induced by a galaxy's spiral arms, bars, galactic winds, black holes and dark matter haloes. It plays an important role in the evolution of spiral galaxies with major consequences for galactic bulges, the transfer of angular momentum, and the distribution of a galaxy's constituent stars, gas and dust. This internal evolution is in turn the key to understanding and testing cosmological models of galaxy formation and evolution. Based on the twenty-third Winter School of the Canary Islands Institute of Astrophysics, this volume presents reviews from nine world-renowned experts on the observational and theoretical research into secular processes, and what these processes can tell us about the structure and formation of galaxies. The volume provides a firm grounding for graduate students and early career researchers working on galactic dynamics and galaxy evolution.
Download or read book Encyclopedia of Astronomy Astrophysics written by P Murdin and published by CRC Press. This book was released on 2001-01-01 with total page 5610 pages. Available in PDF, EPUB and Kindle. Book excerpt: In a unique collaboration, Nature Publishing Group and Institute of Physics Publishing have published the most extensive and comprehensive reference work in astronomy and astrophysics. This unique resource covers the entire field of astronomy and astrophysics and this online version includes the full text of over 2,750 articles, plus sophisticated search and retrieval functionality and links to the primary literature. The Encyclopaedia's authority is assured by editorial and advisory boards drawn from the world's foremost astronomers and astrophysicists. This first class resource is an essential source of information for undergraduates, graduate students, researchers and seasoned professionals, as well as for committed amateurs, librarians and lay people wishing to consult the definitive astronomy and astrophysics reference work.
Download or read book Morphological Evolution of Distant Galaxies from Adaptive Optics Imaging written by Tiffany Michelle Glassman and published by . This book was released on 2003 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt:
