Investigating the Stellar Mass Growth and Quiescence of Massive Galaxies In the Early Universe Using Wide-field Imaging

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ISBN 13 :
Total Pages : 256 pages
Book Rating : 4.:/5 (112 download)

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Book Synopsis Investigating the Stellar Mass Growth and Quiescence of Massive Galaxies In the Early Universe Using Wide-field Imaging by : Matthew Louis Stevans (Jr.)

Download or read book Investigating the Stellar Mass Growth and Quiescence of Massive Galaxies In the Early Universe Using Wide-field Imaging written by Matthew Louis Stevans (Jr.) and published by . This book was released on 2019 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: While galaxies formed stars most actively around z=2, or ~3 Gyr after the Big Bang, when the universal star formation density in the universe peaked. By this time a population of massive galaxies had already formed 1011 - 1012 [solar mass] of stars and some had their star-formation shut off in a process known as quenching. Understanding how these massive galaxies build up their stellar mass and then quench so early in the universe is a fundamental observational test of galaxy evolution. If not obscured by dust, massive galaxies are very bright, and can be observed in the optical and infrared (IR) to probe their redshifted ultraviolet (UV) and optical emission, respectively. The UV emission is produced by newly formed O and B type stars within 100 Myrs of forming, while the rest-frame optical light is produced by stars of all type and traces the stellar mass in the galaxy. By measuring the UV and optical output of galaxies, astronomers can derive star-formation rates and stellar masses. Measuring these properties for large samples of galaxies across a wide dynamic range provides benchmarks for simulations of galaxy formation and evolution physics. The work in this dissertation focuses on completing a wide field imaging survey of galaxies with high UV star-formation rates and high stellar masses at high redshift to perform the most statistically robust census to date. In Chapter 1 we motivate measuring the UV output and the quiescent fraction of high-redshift galaxies. To measure the UV output of massive star-forming galaxies at high redshift we utilize an extensive multi-wavelength dataset assembled in the Spitzer HETDEX Exploratory Large Area Survey (SHELA) Field. The data set includes five bands of deep optical imaging from the Dark Energy Camera (DECam), deep 3.6 micron and 4.5 micron imaging for Spitzer, and J and K [subscript s] imaging for the VISTA-CFHT Stripe 82 (VICS82) Near-infrared Survey. Our extensive dataset compiled from both ground and space-based observatories is uniquely capable of studying the most actively star-forming galaxies which are often very massive galaxies residing in the rarest high-sigma density peaks of the cosmic web. In Chapter 2 we study the bright end of the z=4 galaxy UV luminosity distribution or luminosity function by fitting the spectral energy distributions (SEDs) of the galaxies in our photometric data with Stellar Population Synthesis (SPS) models to measure the galaxies' redshifts and UV luminosity. In addition to measuring the bright end of the galaxy luminosity function, we had the unanticipated result of measuring the faint end of the z=4 active galactic nuclei (AGN) UV luminosity function, which has implications on the contribution of AGNs during the end of the reionization era. We compare our observed galaxy luminosity function to luminosity functions predicted by semi-analytical models (SAMs) with different prescriptions for star formation physics, such as the density of neutral hydrogen. We find our observations are consistent with predictions that galaxies at z=3-4 form stars more efficiently than at lower redshifts due to shorter neutral hydrogen depletion times. In Chapter 3, we measure the fraction of massive (M [subscript *] > 1011 [solar mass] galaxies at z=3-5 in the largest volume to date. To do this we produce a K [subscript s] -selected catalog by combining deep K [subscript s] -band imaging from the NEWFIRM HETDEX survey (NHS), which we obtain, reduce, and catalog. We select quiescent galaxies by performing SED-fitting with SPS models to measure their redshifts, SFRs, and stellar masses. We define quiescent galaxies as having a specific SFR (sSFR; sSFR = SFR / stellar mass)

A Statistical and Multi-wavelength Study of Star Formation in Galaxies

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Publisher : Springer
ISBN 13 : 3319442937
Total Pages : 234 pages
Book Rating : 4.3/5 (194 download)

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Book Synopsis A Statistical and Multi-wavelength Study of Star Formation in Galaxies by : Corentin Schreiber

Download or read book A Statistical and Multi-wavelength Study of Star Formation in Galaxies written by Corentin Schreiber and published by Springer. This book was released on 2016-09-12 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents a pioneering method for gleaning the maximum information from the deepest images of the far-infrared universe obtained with the Herschel satellite, reaching galaxies fainter by an order of magnitude than in previous studies. Using these high-quality measurements, the author first demonstrates that the vast majority of galaxy star formation did not take place in merger-driven starbursts over 90% of the history of the universe, which suggests that galaxy growth is instead dominated by a steady infall of matter. The author further demonstrates that massive galaxies suffer a gradual decline in their star formation activity, providing an alternative path for galaxies to stop star formation. One of the key unsolved questions in astrophysics is how galaxies acquired their mass in the course of cosmic time. In the standard theory, the merging of galaxies plays a major role in forming new stars. Then, old galaxies abruptly stop forming stars through an unknown process. Investigating this theory requires an unbiased measure of the star formation intensity of galaxies, which has been unavailable due to the dust obscuration of stellar light.

Magnificent Constructions

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ISBN 13 :
Total Pages : 180 pages
Book Rating : 4.:/5 (111 download)

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Book Synopsis Magnificent Constructions by : Kevin Christopher Cooke

Download or read book Magnificent Constructions written by Kevin Christopher Cooke and published by . This book was released on 2019 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt: "To understand how the present day universe came to be, we must understand how the massive structures in which we live formed and evolved over the preceding billions of years. Constraining how galaxies grow are the most massive galaxies, called brightest cluster galaxies (BCGs). These luminous and diffuse elliptical galaxies inhabit relaxed positions within their host cluster's gravitational potentials and provide a look at the high mass extreme of galaxy evolution. The relaxed structure, old stellar populations, and central location within the cluster indicate a high redshift formation scenario, however, star-forming BCGs have been observed at much more recent epochs. Addressing this evolutionary complexity, my dissertation consists of four studies to investigate the growth rates of BCGs over several epochs, and how they relate to the growth of the general galaxy population. In my first paper, I present a multiwavelength (far-ultraviolet to far-infrared) study of BCG star formation rates and stellar masses from 0.2 z 0.7 (Cooke et al. 2016), selected from the CLASH and SGAS surveys. I find that in-situ star formation in my sample is consistent with overall quiescence, and star-forming BCGs remain very rare. In my second paper (Cooke et al. 2018), my sample's redshift range is expanded to z ~ 1 with the addition of massive BCGs (M_Stellar 10^11 M_Solar) from galaxy clusters available in the COSMOS X-ray Group Catalog. I find that star formation is roughly constant in our sample of high mass BCGs from 0.3

The First Galaxies

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Publisher : Springer Science & Business Media
ISBN 13 : 3642323626
Total Pages : 434 pages
Book Rating : 4.6/5 (423 download)

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Book Synopsis The First Galaxies by : Tommy Wiklind

Download or read book The First Galaxies written by Tommy Wiklind and published by Springer Science & Business Media. This book was released on 2012-12-15 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt: New observations of the period between the cosmic recombination and the end of reionization are posing intriguing questions about where the first generations of stars were formed, how the first galaxies were assembled, whether these galaxies have low redshift counterparts, and what role the early galaxies played in the reionization process. Combining the new observational data with theoretical models can shed new light on open issues regarding the star formation process, its role in the reionization of the Universe, and the metal enrichment in galaxies at those early epochs. This volume brings together leading experts in the field to discuss our current level of understanding and what may come in the near future as our observational as well as theoretical tools improve. The book confronts the theory of how the first stars, black holes, and galaxies formed with current and planned observations. This synthesis is very timely, just ahead of the establishment of major new facilities, such as the James Webb Space Telescope (JWST), a next-generation, millimeter/sub-millimeter observatory in the Atacama desert (ALMA), and ground-based Extremely Large Telescopes (ELT). Together, they will revolutionize the study of the most distant objects in the Universe. This volume is aimed at beginning graduate students but can also serve as a reference work for active researchers in the field. Apart from presenting the fundamental concepts involved, it also provides an introduction to the methods and techniques used. The book will also be useful to anyone with an astrophysical background who needs an effective starting point for learning about the first stars and galaxies.

Star-forming Galaxies Growing Up Over the Last Ten Billion Years

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ISBN 13 :
Total Pages : 336 pages
Book Rating : 4.:/5 (259 download)

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Book Synopsis Star-forming Galaxies Growing Up Over the Last Ten Billion Years by : Amanda Elaine Bauer

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.

Evolution of Stars and Stellar Populations

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Publisher : John Wiley & Sons
ISBN 13 : 9780470092224
Total Pages : 386 pages
Book Rating : 4.0/5 (922 download)

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Book Synopsis Evolution of Stars and Stellar Populations by : Maurizio Salaris

Download or read book Evolution of Stars and Stellar Populations written by Maurizio Salaris and published by John Wiley & Sons. This book was released on 2005-12-13 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: Evolution of Stars and Stellar Populations is a comprehensive presentation of the theory of stellar evolution and its application to the study of stellar populations in galaxies. Taking a unique approach to the subject, this self-contained text introduces first the theory of stellar evolution in a clear and accessible manner, with particular emphasis placed on explaining the evolution with time of observable stellar properties, such as luminosities and surface chemical abundances. This is followed by a detailed presentation and discussion of a broad range of related techniques, that are widely applied by researchers in the field to investigate the formation and evolution of galaxies. This book will be invaluable for undergraduates and graduate students in astronomy and astrophysics, and will also be of interest to researchers working in the field of Galactic, extragalactic astronomy and cosmology. comprehensive presentation of stellar evolution theory introduces the concept of stellar population and describes "stellar population synthesis" methods to study ages and star formation histories of star clusters and galaxies presents stellar evolution as a tool for investigating the evolution of galaxies and of the universe in general

Exploring the Interplay Between Star Formation and Active Galactic Nuclei and the Role of Environment in Galaxy Evolution

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Publisher :
ISBN 13 :
Total Pages : 432 pages
Book Rating : 4.:/5 (126 download)

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Book Synopsis Exploring the Interplay Between Star Formation and Active Galactic Nuclei and the Role of Environment in Galaxy Evolution by : Jonathan Florez

Download or read book Exploring the Interplay Between Star Formation and Active Galactic Nuclei and the Role of Environment in Galaxy Evolution written by Jonathan Florez and published by . This book was released on 2021 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the central goals of extragalactic astronomy is to understand how galaxies grow their stellar mass and central black holes, the connection between star formation and active galactic nuclei (AGN), and the impact of environment on this growth. In this thesis, I utilize multiwavelength surveys that are both deep and wide, advanced computational codes that model the spectral energy distributions of galaxies with and without AGN, as well as state-of-the-art simulations of galaxy evolution in order to explore how galaxy properties are impacted by their surrounding environment and AGN activity. These studies explore galaxies over a redshift range of 0.015 z 0.023 (lookback time of ~ 0.2 to ~ 0.3 Gyr), and over a redshift range of 0.5 z 3.0 (lookback time of ~ 5 to ~ 12 Gyr). The large-area surveys used here provide some of the largest and most statistically robust samples to-date of rare massive galaxies (with stellar mass M [subscript *] 1011 M☉) and extremely luminous AGN (with X-ray luminosity L [subscript X] 1044 erg s−1) out to z ~ 3, thereby limiting the effects of cosmic variance and Poisson statistics. I analyze the observed stellar masses and star formation rates of galaxies as a function of environment and AGN activity, compare the empirical results to theoretical models of galaxy evolution, and discuss the implications of such comparisons. This work will provide significant guidance and constraints to the future development of theoretical models of galaxy growth. In Chapter 2 (Florez et al. 2021, ApJ, 906, 97) I measure the environmental dependence, where environment is defined by the distance to the third nearest neighbor, of multiple galaxy properties inside the Environmental COntext (ECO) catalog. I focus primarily on void galaxies at redshifts z = 0.015 - 0.023, which I define as the 10% of galaxies having the lowest local density. I compare the properties of void and non-void galaxies: baryonic mass, color, fractional stellar mass growth rate (FSMGR), morphology, and gas-to-stellar-mass ratio. The void galaxies typically have lower baryonic masses than galaxies in denser environments, and they display the properties expected of a lower mass population: they have more late-types, are bluer, have higher FSMGR, and are more gas rich. I also control for baryonic mass and investigate the extent to which void galaxies are different at fixed mass. I find that void galaxies are bluer, more gas-rich, and more star forming at fixed mass than non-void galaxies, which is a possible signature of galaxy assembly bias and other environmental processes. Furthermore, I show that these trends persist even at fixed mass and morphology, and I find that voids host a distinct population of early-types that are bluer and more star-forming than the typical red and quenched early-types. In addition to these empirical observational results, I also present theoretical results from mock catalogs with built-in galaxy assembly bias. I show that a simple matching of galaxy properties to (sub)halo properties, such as mass and age, can recover the observed environmental trends in the local galaxy population. In Chapter 3 (Florez et al. 2020, MNRAS, 497, 3273) I investigate the relation between AGN and star formation activity at 0.5 z 3 by analyzing 898 galaxies with high X-ray luminosity AGN (L [subscript X] 1044 erg s−1) and a large comparison sample of ~ 320,000 galaxies without such AGN. My samples are selected from a large (11.8 deg2) area in Stripe 82 that has multi-wavelength (X-ray to far-IR) data. The enormous comoving volume (~ 0.3 Gpc3) at 0.5

Panoramic Views of Galaxy Formation and Evolution

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ISBN 13 :
Total Pages : 572 pages
Book Rating : 4.3/5 (91 download)

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Book Synopsis Panoramic Views of Galaxy Formation and Evolution by : Tadayuki Kodama

Download or read book Panoramic Views of Galaxy Formation and Evolution written by Tadayuki Kodama and published by . This book was released on 2008 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt: "These proceedings of the first meeting of the Subaru International Conference Series held in December 2007 in Hayama, Japan, provide unique up-to-date overviews of the history of galaxy formation and the evolution of the universe. Fascinating and comprehensive observational results as well as many important theoretical achievements were presented by more than 150 active researchers from more than 15 countries and regions. The conference started off with results from recent cutting-edge observations of the very high-redshift universe extending into the cosmic reionization era, together with some theoretical interpretations and predictions for the first generation of galaxies. The history of mass distributions and structure formation at later cosmic times, including clusters of galaxies, was discussed extensively in presentations based on various panoramic survey data sets. Our aim was to showcase and understand the intrinsic galaxy-formation bias in the high-redshift universe and also the role of external environmental effects during the hierarchical assembly of galaxies into denser regions. Various populations of distant galaxies at different redshifts, discovered and studies by many different techniques, were introduced along with the physical relationship between these populations. Our discussion were aimed at assembling these pieces of jigsaw puzzles together into a panoramic and yet detailed structures of the Milky Way Galaxy and the Local Group galaxies were also presented and discussed as a complementary approach to the studies of the high-redshift Universe. In total, 19 invited talks, 46 contributed talks, and 87 poster papers combined to build up a picture of the history of galaxies over the cosmic age. This book is suitable for researchers who are interested in both observational and theoretical aspects of galaxy formation and cosmology, and especially for students seeking an overview of knowledge about galaxy formation to date."--Publisher's website

Star-Formation Rates of Galaxies

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Publisher : Cambridge University Press
ISBN 13 : 1316877523
Total Pages : 318 pages
Book Rating : 4.3/5 (168 download)

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Book Synopsis Star-Formation Rates of Galaxies by : Andreas Zezas

Download or read book Star-Formation Rates of Galaxies written by Andreas Zezas and published by Cambridge University Press. This book was released on 2021-04-29 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt: Star-formation is one of the key processes that shape the current state and evolution of galaxies. This volume provides a comprehensive presentation of the different methods used to measure the intensity of recent or on-going star-forming activity in galaxies, discussing their advantages and complications in detail. It includes a thorough overview of the theoretical underpinnings of star-formation rate indicators, including topics such as stellar evolution and stellar spectra, the stellar initial mass function, and the physical conditions in the interstellar medium. The authors bring together in one place detailed and comparative discussions of traditional and new star-formation rate indicators, star-formation rate measurements in different spatial scales, and comparisons of star-formation rate indicators probing different stellar populations, along with the corresponding theoretical background. This is a useful reference for students and researchers working in the field of extragalactic astrophysics and studying star-formation in local and higher-redshift galaxies.

High-Redshift Galaxies

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Publisher : Springer Science & Business Media
ISBN 13 : 3540758240
Total Pages : 353 pages
Book Rating : 4.5/5 (47 download)

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Book Synopsis High-Redshift Galaxies by : Immo Appenzeller

Download or read book High-Redshift Galaxies written by Immo Appenzeller and published by Springer Science & Business Media. This book was released on 2009-06-17 with total page 353 pages. Available in PDF, EPUB and Kindle. Book excerpt: The high-redshift galaxies became a distinct research ?eld during the ?nal decade of the20thcentury. AtthattimetheLyman-breaktechniquemadeitpossibletoidentify signi?cant samples of such objects, and the new generation of 8 to 10-m telescopes resulted in ?rst good spectroscopic data. Today the high-redshift galaxies have developed into one of the important topics of astrophysics, accounting for about 5–10% of the publications in the major scienti?c journals devoted to astronomy. Because high-redshift galaxies is a rapidly developing ?eld and since new results are published constantly, writing a book on this topic is challenging. On the other hand, in view of the large amount of individual results now in the literature, and in view of the still growing interest in this topic, it appears worthwhile to summarize and evaluate the available data and to provide an introduction for those who wish to enter this ?eld, or who, for various reasons, might be interested in its results. The end of the ?rst decade of the 21st century appears to be a good point in time to attempt such a summary. The current generation of ground-based 8 to 10-m - optical telescopes, the Hubble Space Telescope, and the most important large radio telescopes have by now been in operation since about one or two decades. Although these instruments will continue to produce important scienti?c results for some time to come, many of the initial programs exploiting their unique new possibilities have been completed.

The Properties of Massive Galaxies at Cosmic Noon

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Publisher :
ISBN 13 :
Total Pages : 310 pages
Book Rating : 4.:/5 (126 download)

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Book Synopsis The Properties of Massive Galaxies at Cosmic Noon by : Sydney Beth Sherman

Download or read book The Properties of Massive Galaxies at Cosmic Noon written by Sydney Beth Sherman and published by . This book was released on 2021 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt: The formation and evolution of massive galaxies in the first few billion years after the Big Bang remain important questions in extragalactic astronomy. Technological advancements allowing for multi-wavelength surveys that are both wide, covering large portions of the sky, and deep, pushing studies to higher redshifts, have opened the door for statistically significant studies of rare and important populations of galaxies at early times. Massive galaxies (with stellar mass M [subscript ★] > 1011M [subscript ⊙]) provide an excellent testbed for theoretical models of galaxy evolution, however, because they have low number densities, large area surveys are required in order to locate uniformly-selected, statistically significant samples of these objects. In this thesis I detail the methods used to locate the largest samples to date of these massive galaxies, I investigate their number densities, quenched fractions, and specific star-formation rates, and I perform detailed comparisons of my empirical results with predictions from theoretical models. This work is a significant advancement as it mitigates uncertainties from Poisson statistics and cosmic variance, effects which have historically limited studies of the massive galaxy population at cosmic noon. Key results are summarized below. In Chapter 2 (Sherman et al. 2020a, MNRAS, 491, 3318) I present the high-mass end of the galaxy stellar mass function using a gri-selected sample of 5,352 star-forming galaxies with M [subscript ★] > 1011M [subscript ⊙] at cosmic noon, 1.5

Old Stellar Populations

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Publisher : John Wiley & Sons
ISBN 13 : 3527665544
Total Pages : 506 pages
Book Rating : 4.5/5 (276 download)

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Book Synopsis Old Stellar Populations by : Santi Cassisi

Download or read book Old Stellar Populations written by Santi Cassisi and published by John Wiley & Sons. This book was released on 2013-08-29 with total page 506 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book discusses the theoretical path to decoding the information gathered from observations of old stellar systems. It focuses on old stellar systems because these are the fossil record of galaxy formation and provide invaluable information ont he evolution of cosmic structures and the universe as a whole. The aim is to present results obtained in the past few years for theoretical developments in low mass star research and in advances in our knowledge of the evolution of old stellar systems. A particularly representative case is the recent discovery of multiple stellar populations in galactic globular clusters that represents one of the hottest topics in stellar and galactic astrophysics and is discussed in detail. Santi Cassisi has authored about 270 scientific papers, 150 of them in peer-reviewed journals, and the title Evolution of Stars and Stellar Populations.

The Intriguing Life of Massive Galaxies (IAU S295)

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Publisher : Cambridge University Press
ISBN 13 : 9781107033849
Total Pages : 0 pages
Book Rating : 4.0/5 (338 download)

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Book Synopsis The Intriguing Life of Massive Galaxies (IAU S295) by : Daniel Thomas

Download or read book The Intriguing Life of Massive Galaxies (IAU S295) written by Daniel Thomas and published by Cambridge University Press. This book was released on 2013-09-26 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The lives of massive galaxies are affected by many key processes, including gas accretion and star formation, feedback and quenching, black hole growth, mass assembly, galaxy mergers and interactions, chemical enrichment and stellar populations, dark matter, galaxy haloes, and satellite accretion. These proceedings of IAU Symposium 295 discuss recent progress in galaxy formation and evolution, and plan ahead for future challenges. They cover, from both theoretical and observational perspectives, the lives of massive galaxies from the formation of the first galaxies in the early Universe, through their evolution with cosmic time to massive galaxies in the local Universe. Key contributions deal with recent and near-future advances in telescope technology and massive galaxy surveys as well as computer power for large-scale simulations. IAU S295 benefits advanced students and active researchers who need an up-to-date review of galaxy formation and evolution and its future prospects.

New Worlds, New Horizons in Astronomy and Astrophysics

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Publisher : National Academies Press
ISBN 13 : 0309157994
Total Pages : 324 pages
Book Rating : 4.3/5 (91 download)

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Book Synopsis New Worlds, New Horizons in Astronomy and Astrophysics by : National Research Council

Download or read book New Worlds, New Horizons in Astronomy and Astrophysics written by National Research Council and published by National Academies Press. This book was released on 2011-02-04 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: Driven by discoveries, and enabled by leaps in technology and imagination, our understanding of the universe has changed dramatically during the course of the last few decades. The fields of astronomy and astrophysics are making new connections to physics, chemistry, biology, and computer science. Based on a broad and comprehensive survey of scientific opportunities, infrastructure, and organization in a national and international context, New Worlds, New Horizons in Astronomy and Astrophysics outlines a plan for ground- and space- based astronomy and astrophysics for the decade of the 2010's. Realizing these scientific opportunities is contingent upon maintaining and strengthening the foundations of the research enterprise including technological development, theory, computation and data handling, laboratory experiments, and human resources. New Worlds, New Horizons in Astronomy and Astrophysics proposes enhancing innovative but moderate-cost programs in space and on the ground that will enable the community to respond rapidly and flexibly to new scientific discoveries. The book recommends beginning construction on survey telescopes in space and on the ground to investigate the nature of dark energy, as well as the next generation of large ground-based giant optical telescopes and a new class of space-based gravitational observatory to observe the merging of distant black holes and precisely test theories of gravity. New Worlds, New Horizons in Astronomy and Astrophysics recommends a balanced and executable program that will support research surrounding the most profound questions about the cosmos. The discoveries ahead will facilitate the search for habitable planets, shed light on dark energy and dark matter, and aid our understanding of the history of the universe and how the earliest stars and galaxies formed. The book is a useful resource for agencies supporting the field of astronomy and astrophysics, the Congressional committees with jurisdiction over those agencies, the scientific community, and the public.

On the Formation of the Most Massive Stars in the Galaxy

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Publisher : Springer Science & Business Media
ISBN 13 : 1461433088
Total Pages : 131 pages
Book Rating : 4.4/5 (614 download)

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Book Synopsis On the Formation of the Most Massive Stars in the Galaxy by : Roberto J. Galván-Madrid

Download or read book On the Formation of the Most Massive Stars in the Galaxy written by Roberto J. Galván-Madrid and published by Springer Science & Business Media. This book was released on 2012-06-08 with total page 131 pages. Available in PDF, EPUB and Kindle. Book excerpt: The most massive stars in the galaxy - those with more than 15 to 20 solar masses - are lilkely to ionize their surroundings before they reach their final mass. How can they accrete in spite of the presence of over-pressurized gas? This thesis presents results of Submillimeter Array (SMA) and Very Large Array (VLA) studies of massive star formation regions in the early stages of ionization, as well as an analysis of numerical simulations of the evolution of these young HII regions. The results favor a picture in which very massive stars form in accretion flows that are partially ionized and that keep accreting material from their environment.

Galaxy Formation and Mergers with Stars and Massive Black Holes

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Publisher : Stanford University
ISBN 13 :
Total Pages : 189 pages
Book Rating : 4.F/5 ( download)

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Book Synopsis Galaxy Formation and Mergers with Stars and Massive Black Holes by : Chi-hun Kim

Download or read book Galaxy Formation and Mergers with Stars and Massive Black Holes written by Chi-hun Kim and published by Stanford University. This book was released on 2011 with total page 189 pages. Available in PDF, EPUB and Kindle. Book excerpt: While mounting observational evidence suggests the coevolution of galaxies and their embedded massive black holes (MBHs), a comprehensive astrophysical understanding which incorporates both galaxies and MBHs has been missing. To tackle the nonlinear processes of galaxy formation, we develop a state-of-the-art numerical framework which self-consistently models the interplay between galactic components: dark matter, gas, stars, and MBHs. Utilizing this physically motivated tool, we present an investigation of a massive star-forming galaxy hosting a slowly growing MBH in a cosmological LCDM simulation. The MBH feedback heats the surrounding gas and locally suppresses star formation in the galactic inner core. In simulations of merging galaxies, the high-resolution adaptive mesh allows us to observe widespread starbursts via shock-induced star formation, and the interplay between the galaxies and their embedding medium. Fast growing MBHs in merging galaxies drive more frequent and powerful jets creating sizable bubbles at the galactic centers. We conclude that the interaction between the interstellar gas, stars and MBHs is critical in understanding the star formation history, black hole accretion history, and cosmological evolution of galaxies. Expanding upon our extensive experience in galactic simulations, we are well poised to apply this tool to other challenging, yet highly rewarding tasks in contemporary astrophysics, such as high-redshift quasar formation.

On the Evolution of Massive Galaxies

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Publisher :
ISBN 13 :
Total Pages : 498 pages
Book Rating : 4.:/5 (769 download)

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Book Synopsis On the Evolution of Massive Galaxies by : Kristen Leah Shapiro

Download or read book On the Evolution of Massive Galaxies written by Kristen Leah Shapiro and published by . This book was released on 2010 with total page 498 pages. Available in PDF, EPUB and Kindle. Book excerpt: Galaxies, as the fundamental building blocks of the Universe, are the critical link between the overall evolution of the Universe and the assembly of small-scale structures, such as stars and planets, within it. Unfortunately, the formation and evolution of galaxies remains poorly understood, due to the incredible complexity of the physics that governs these processes. To study and constrain these processes, a particularly useful galaxy population are bulge-dominated galaxies such as elliptical and large spiral galaxies, which together are the most massive and most evolved components of the local Universe. In the present day, these galaxies are dominated by old stars; however, their histories likely include an epoch of powerful star formation and rapid growth of their supermassive black holes. Progress in understanding the evolution of massive galaxies can therefore proceed on two fronts -- 1) observations of their formation in situ in the early Universe, and 2) detailed studies of the fossil relics of this process in the local Universe -- with the ultimate goal being to link progenitors and descendants. A key epoch for such investigations is 10 billion years ago, the most active period in the Universe's history, at which time the vast majority of stellar material in galaxies was assembled. Recent comparisons of the observed properties of galaxy populations across cosmic time have shown that the dominant star-forming galaxy population at these early times were the probable ancestors of present-day massive (bulge-dominated spiral and elliptical) galaxies. The obvious direction for current and future research is therefore to probe the detailed evolution with time of the properties and sub-structures that define this local galaxy population. This goal has guided my dissertation research, as described in the following pages. Using photometric, spectroscopic, and integral-field observations at optical through mid-infrared wavelengths, I have studied both star-forming galaxies in the early Universe and their present-day descendants. Specifically, this thesis explores the dynamical, star-forming, and black hole properties of galaxies 10 billion years ago and shows that these young galaxies must be assembled via a rapid but steady influx of gas from the surrounding cosmic structure. The resulting large quantity of gas in these galaxies causes super-large star-forming gas clouds to form, and the dynamical interactions of these clouds control the evolution of the galaxies' supermassive black holes and internal sub-structures, producing the bulges and globular cluster populations observed in the present day. Studies of the resulting local massive galaxy population, also presented herein, confirm that such successive minor dynamical disturbances were important to the assembly of these bulge-dominated galaxies and their supermassive black holes. In the pages of this thesis, an exciting link is emerging in which many observed properties of local galaxies can be explained by the dramatic internal processes occurring in galaxies 10 billion years ago, during the era of the most rapid galaxy assembly.