Models of Star Formation in Interacting and Merging Disk Galaxies PDF Download

Author: James Christopher Mihos
Publisher:
ISBN:
Category : Active galaxies
Languages : en
Pages : 278

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Author: Chi-hun Kim
Publisher: Stanford University
ISBN:
Category :
Languages : en
Pages : 189

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Book Description
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.

Author: Thomas J. Cox
Publisher:
ISBN:
Category :
Languages : en
Pages : 364

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Author: Carrie Ruth Bridge
Publisher:
ISBN: 9780494393765
Category :
Languages : en
Pages : 270

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Book Description
Hierarchical models and observations show that galaxy mergers and interactions play a key role in galaxy assembly and star formation, but to what extent is still unclear. This thesis attempts to quantify their contribution to galaxy evolution by probing the number of interactions and mergers, along with their star forming properties as a function of redshift. The presence of long tidal tails and bridges are robust signatures of recent merger activity. This completely dynamical phenomenon was used to develop a new classification scheme to identify interacting galaxies and probe the interaction fraction and merger rate. We applied this new technique to large area, multi-band imaging obtained via the Canada France Hawaii Telescope Legacy Survey (CFHTLS-Deep), yielding the first statistically secure, lower limit of the galaxy interaction fraction between 0.1 z 1.0. Optically, the fraction of galaxies undergoing an interaction evolves moderately with redshift as (1 + z)2.24+/-0.24The Spitzer 24mum coverage of both the Extragalactic First Look Survey (XFLS) and CFHTLSDeep Survey were used to carry out one of the first and largest merger studies of IR bright galaxies. Within the ACS component of the XFLS, interactions were identified over the full merger sequence using traditional techniques, finding a merger rate increase for 24microm galaxies of (1 + z) & sim;2. This result implies that merging is an increasingly important process in the evolution of luminous IR galaxies (LIRGs), contributing 40--60% of the IR luminosity density and at least 30--40% of the star formation rate density at z & sim; 1. Galaxy interactions at all stages are found to have elevated star formation rates greater than a factor of two-four (on average) and a higher incidence of AGN activity compared to non-interacting field galaxies. This result supports a causal connection between galaxy merging, induced star formation, and AGN activity. Ultimately, major mergers provide a moderate contribution to the evolution of the cosmic star formation rate density and IR luminosity density to z & sim; 1, with an increasing trend suggesting that merging plays a larger role at higher redshifts (z 1). It is also clear that merging plays a significant role in triggering the processes that power the IR emission of LIRG galaxies at z 0.5.

Author: Robert C. Kennicutt Jr.
Publisher: Springer Science & Business Media
ISBN: 3540316302
Category : Science
Languages : en
Pages : 417

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Book Description
This volume contains the written versions of the lectures given at the 26th course of the renowned Saas-Fee series. The book represents a comprehensive and up-to-date review of the field of galaxy interaction. Nowadays, galaxies are no longer seen as immutable objects: they evolve, interact, merge, blaze, and reshape. Dynamic forces can induce powerful stellar activity able to transform the matter composition and morphology of galaxies. The lectures included in this book aim at a better understanding of these remarkable and fascinating phenomena. Though the book is intended for graduate students and young post-docs in astrophysics, it contains more advanced and original material, as well as historical perspectives, which will be of great interest to experts and astronomy teachers also.

Author: G. Hensler
Publisher: Springer Science & Business Media
ISBN: 9401733155
Category : Science
Languages : en
Pages : 684

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Book Description
Galaxies have a history: distant galaxies, formed early in the life of the universe, differ from the nearby ones. This book addresses the modeling of galaxy evolution from their cosmological formation to their presently observable structures, presenting the state of the art in the field.

Author: Nickolay Y. Gnedin
Publisher: Springer
ISBN: 3662478900
Category : Science
Languages : en
Pages : 375

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Book Description
This book contains the elaborated and updated versions of the 24 lectures given at the 43rd Saas-Fee Advanced Course. Written by four eminent scientists in the field, the book reviews the physical processes related to star formation, starting from cosmological down to galactic scales. It presents a detailed description of the interstellar medium and its link with the star formation. And it describes the main numerical computational techniques designed to solve the equations governing self-gravitating fluids used for modelling of galactic and extra-galactic systems. This book provides a unique framework which is needed to develop and improve the simulation techniques designed for understanding the formation and evolution of galaxies. Presented in an accessible manner it contains the present day state of knowledge of the field. It serves as an entry point and key reference to students and researchers in astronomy, cosmology, and physics.

Author: Curtis Struck
Publisher: Springer Science & Business Media
ISBN: 0387853715
Category : Science
Languages : en
Pages : 292

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Book Description
The spectacular images of galaxy collisions capture the imagination. This book will show what is out there in the universe, what it’s like in other galaxies, what they might look like, and how cosmic processes might affect life in other solar systems. It will explain crucial stages in the development of physical structure in the universe, and the effect of galaxy scale processes. Professor Struck will explore all the issues surrounding galaxy collisions. He will begin with a brief broad review of the background on galaxies, the history of their discovery, and how this has been driven by steadily improving technology. Chapters 2 gives details of the early stages of different types of galaxy collision - Rings of Fire, Tidal Swings and Retrograde and Sideways Reels - while Chapter 3 describes collisions between galaxies of very different masses: minor merger or dwarf destruction. Chapter 4 covers ultra-luminous infrared galaxies and major mergers and Chapter 5 briefly examines the techniques used for computer simulation results and how increasing computer capacity has affected the development of this field. The following chapter looks at understanding the physical processes of triggered star formation and nuclear activity. Chapters 7-9 look at the broader view of cosmological structure growth which determines the environment and conditions in which galaxy collisions occur. In the densest environments, this process repeats itself on the larger scale of galaxy clusters. The concluding chapter considers what a galaxy collision looks like from a solar system like ours. Although the galaxy is completely restructured and the night sky view would change greatly over the course of several hundred million years, the direct effects on our planet would be few and infrequent, with only a small probability of being truly catastrophic. These issues will be explored along with the ideas that galaxies must reach a certain evolutionary "maturity" before they can even form solar systems, and that there are habitable zones within galaxies. Thus, galaxy scale processes, like collisions, can determine the fate of life on Earth-like planets.

Author: Ji-hoon Kim
Publisher:
ISBN:
Category : Galaxies
Languages : en
Pages :

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Book Description
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.

Author: Steff Jaywan
Publisher: Dedona Publishing
ISBN:
Category : Science
Languages : en
Pages : 29

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Book Description
Galaxies are dynamic entities, constantly evolving through processes like mergers, collisions, and interactions with neighboring galaxies. When galaxies merge, their stars, gas, and dust can undergo dramatic transformations, leading to the formation of new stars and restructuring of the galaxy's shape. These interactions can trigger intense bursts of star formation and feed supermassive black holes at the galaxies' centers, leading to the emission of powerful jets of radiation. Furthermore, galaxies are not isolated entities but are interconnected within the vast cosmic web of the universe. They cluster together in groups and clusters, bound by their mutual gravitational attraction. These clusters can contain hundreds or even thousands of galaxies, each influencing the others' evolution through gravitational interactions and tidal forces. The study of galaxies encompasses various fields of astrophysics, including observational astronomy, theoretical modeling, and simulations. Observational techniques, such as telescopes operating across different wavelengths of light and gravitational wave detectors, allow astronomers to peer into the depths of galaxies across cosmic time.