Download or read book The Interplay Between Stars Gas and Dust in Faint Star forming Galaxies written by and published by . This book was released on 2019 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stars Gas and Dust in Galaxies written by Danielle M. Alloin and published by . This book was released on 2000 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Galaxies written by Steff Jaywan and published by Dedona Publishing. This book was released on with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Dust in Galaxies written by David A Williams and published by Royal Society of Chemistry. This book was released on 2019-12-12 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: Without interstellar dust, the Universe as we see it today would not exist. Yet at first we considered this vital ingredient merely an irritating fog that prevented a clear view of the stars and nebulae in the Milky Way and other galaxies. We now know that interstellar dust has essential roles in the physics and chemistry of the formation of stars and planetary systems, the creation of the building blocks of life, and in the movement of those molecules to new planets. This is the story in this book. After introducing the materials this interstellar dust is made of, the authors explain the range of sizes and shapes of the dust grains in the Milky Way galaxy and the life cycle of dust, starting from the origins of dust grains in stellar explosions through to their turbulent destruction. Later on we see the variety of processes in interstellar space involving dust and the events there that cause the dust to change in ways that astronomers and astrobiologists can use to indirectly observe those events. This book is written for a general audience, concentrating on ideas rather than detailed mathematics and chemical formulae, and is the first time interstellar dust has been discussed at an accessible level.

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.

Download or read book The Interplay Between Massive Star Formation the ISM and Galaxy Evolution written by D. Kunth and published by Atlantica Séguier Frontières. This book was released on 1996 with total page 668 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book How Did the First Stars and Galaxies Form written by Abraham Loeb and published by Princeton University Press. This book was released on 2010-07-19 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt: A concise introduction to cosmology and how light first emerged in the universe Though astrophysicists have developed a theoretical framework for understanding how the first stars and galaxies formed, only now are we able to begin testing those theories with actual observations of the very distant, early universe. We are entering a new and exciting era of discovery that will advance the frontiers of knowledge, and this book couldn't be more timely. It covers all the basic concepts in cosmology, drawing on insights from an astronomer who has pioneered much of this research over the past two decades. Abraham Loeb starts from first principles, tracing the theoretical foundations of cosmology and carefully explaining the physics behind them. Topics include the gravitational growth of perturbations in an expanding universe, the abundance and properties of dark matter halos and galaxies, reionization, the observational methods used to detect the earliest galaxies and probe the diffuse gas between them—and much more. Cosmology seeks to solve the fundamental mystery of our cosmic origins. This book offers a succinct and accessible primer at a time when breathtaking technological advances promise a wealth of new observational data on the first stars and galaxies. Provides a concise introduction to cosmology Covers all the basic concepts Gives an overview of the gravitational growth of perturbations in an expanding universe Explains the process of reionization Describes the observational methods used to detect the earliest galaxies

Download or read book Probing the Stellar Gaseous and Dust Properties of Galaxies Through Analysis of Their Spectral Energy Distributions written by Rafael T. Eufrasio and published by . This book was released on 2015 with total page 159 pages. Available in PDF, EPUB and Kindle. Book excerpt: The spectral energy distributions (SEDs) of galaxies are shaped by their physical properties and they are our primary source of information on galaxies stellar, gaseous, and dust content. Nearby galaxies (less than 100 Mpc away) are spatially resolved by current telescopes from the ultraviolet (UV) to radio wavelengths, allowing the study of the SEDs of subgalactic regions. Such studies are necessary for deriving maps and spatial trends of the physical properties across a galaxy. In principle, the complex history of the formation, growth, and evolution of a galaxy or a region of a galaxy can be inferred from its radiative output. In practice, this task is complicated by the fact that a significant fraction of the star formation activity takes place in dust obscured regions, in which a significant fraction of the stellar radiative output is absorbed, scattered, and reradiated by the gas and dust in the interstellar medium (ISM). This reprocessing of the stellar radiation takes place in ionized interstellar gas regions (H II regions) surrounding massive hot stars, in diffuse atomic gas (H I regions), and in dense molecular clouds. For this work, we have analyzed two galaxies in detail, NGC 6872 and NGC 6946, also known as Condor and Fireworks Galaxy, respectively. The Condor galaxy is the largest-known spiral galaxy. It is part a group of galaxies, the Pavo group, with 12 other galaxies. It has, however, interacted in the past ~150 Myr with a smaller companion, previously believed to have shaped the physical extent of the giant spiral. We have performed detailed SED fitting from the UV to mid-infrared (mid-IR) to obtain star formation histories of seventeen sub-galactic regions across the Condor. These regions are large enough to be galaxies themselves, with 32.3 million light-years in diameter. We find that the Condor was already very massive before this interaction and that it was much less affected by the passage of the companion than previously thought. We also found that a significant fraction of the 22 micron flux, usually considered a complementary measure of the UV-optically determined star formation rate (SFR), is not associated with the recent (last 100 Myr) star formation activity. A fraction of the 22 micron flux represents the energy reradiated by dust heated by intermediate age, long-lived stars. For the Fireworks galaxy, data coverage from the UV to radio allowed us to measure the full radiative budget from the stellar emission (bolometric luminosities) and the fraction coming from reprocessing by dust and gas in the IR. We present a self-consistent, physically-motivated model to describe SEDs of subgalactic regions across the galaxy, which simultaneously fits the stellar attenuated SED from UV to mid-infrared emission, the reradiated infrared emission from the dust, the radio continuum emission from the gas, as well as the intensity of select recombination lines from the ionized gas. We present a framework capable of determine the IR fraction not associated with the recent SFR. This work provides a novel and crucial step towards understanding the physical processes responsible for various empirical laws to determine SFR in galaxies, the correlation between the IR and stellar emission, and the physical conditions of the ISM. It provides essential inputs for more detailed modeling of the spatially-resolved photometric and chemical (dust and gas) evolution of galaxies.

Download or read book Molecular Gas Dust and Star Formation in Galaxies IAU S292 written by Tony Wong and published by Cambridge University Press. This book was released on 2013-04-11 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Our knowledge of the molecular gas content in galaxies has advanced rapidly in the past decade with systematic surveys from ground-based radio facilities, coupled with advances in observations and modeling of the thermal dust emission associated with the gas. This Symposium Proceedings provides a timely overview of the latest observations of molecular gas and dust in the Milky Way and in other galaxies. It also covers related topics including the initial conditions for star formation, observational tracers of star formation and interstellar conditions, and simulations of the turbulent, multiphase interstellar medium. Featuring ten review articles by leaders in the field, and including early results and prospects for the ALMA observatory, this volume will prove especially useful for graduate students or scientists who are pursuing or planning research in this area.

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.

Download or read book A Question and Answer Guide to Astronomy written by Pierre-Yves Bely and published by Cambridge University Press. This book was released on 2017-03-23 with total page 361 pages. Available in PDF, EPUB and Kindle. Book excerpt: Contains 250 questions and answers about astronomy, particular for the amateur astronomer.

Download or read book Gas and Dust in Regions of Recent Star Formation written by Jason A. Cardelli and published by . This book was released on 1985 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Physics of the Interstellar Medium Second Edition written by J.E Dyson and published by CRC Press. This book was released on 1997-01-01 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book leads the advanced undergraduate through the wide range of disciplines related to an understanding of the interstellar medium and is suitable for any student studying either physics or astrophysics. The study of the interstellar medium incorporates a large range of physical More...processes on both large and small scales all of which are covered in this text. Together with the inclusion of simple models and problems at the end of each chapter this text provides a comprehensive overview and grounding in the study of the interstellar medium.

Download or read book Gas Accretion onto Galaxies written by Andrew Fox and published by Springer. This book was released on 2017-03-23 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: This edited volume presents the current state of gas accretion studies from both observational and theoretical perspectives, and charts our progress towards answering the fundamental yet elusive question of how galaxies get their gas. Understanding how galaxies form and evolve has been a central focus in astronomy for over a century. These studies have accelerated in the new millennium, driven by two key advances: the establishment of a firm concordance cosmological model that provides the backbone on which galaxies form and grow, and the recognition that galaxies grow not in isolation but within a “cosmic ecosystem” that includes the vast reservoir of gas filling intergalactic space. This latter aspect in which galaxies continually exchange matter with the intergalactic medium via inflows and outflows has been dubbed the “baryon cycle”. The topic of this book is directly related to the baryon cycle, in particular its least well constrained aspect, namely gas accretion. Accretion is a rare area of astrophysics in which the basic theoretical predictions are established, but the observations have been as yet unable to verify the expectations. Accretion has long been seen around the Milky Way in so-called High Velocity Clouds, but detecting accretion even around nearby galaxies has proved challenging; its multi-phase nature requires sensitive observations across the electromagnetic spectrum for full characterization. A promising approach involves looking for kinematic signatures, but accretion signatures are often confused with internal motions within galaxies. Accretion studies therefore touch a wide range of astrophysical processes, and hence a wide cross-section of the astronomical community. As observational facilities are finally able to access the wavelength ranges and depths at which accretion processes may be manifest, the time is right to survey these multiple lines of investigation and determine the state of the field in accretion studies of the baryon cycle.

Download or read book Faint Objects and How to Observe Them written by Brian Cudnik and published by Springer Science & Business Media. This book was released on 2012-09-18 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: Faint Objects and How to Observe Them is for visual observers who are equipped with a 10-inch or larger astronomical telescope and who want to "go deep" with their observing. It provides a guide to some of the most distant, dim, and rarely observed objects in the sky, supported by background information on surveys and objects lists - some familiar, such as Caldwell, and some not so familiar. This book not only provides a wealth of experience compiled from several sources, but it also gives an historical background to surveys whose names may or may not be familiar to most amateur astronomers. Finally, it includes a listing of the many galaxy clusters out there, from "nearby" ones such as Stefan's Quintet to some of the most distant groups observable through the largest telescopes.

Download or read book The Stellar Gas and Dust Properties of 0 5 written by Gautam Nagaraj and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Galaxies form and evolve on timescales much longer than astronomers' careers. Nevertheless, by observing many galaxies at various epochs of cosmic time and developing physical models of the universe, we can converge on a more complete picture of the grand history of these majestic conglomerations of stars, gas, dust, black holes, and dark matter. Once galaxies and their distances from Earth have been identified, we use their integrated light signatures--their spectral energy distributions (SEDs)--to analyze their contents. Developing more accurate yet faster approaches to determine the physical properties of galaxies based on their SEDs is crucial as we dive into the era of big astronomical data with more extensive and sensitive observations of the cosmos than ever before. One of the most important ways to identify star-forming galaxies is by measuring the strengths of emission lines arising from ionized gas near massive stars. From a pool of over 9,000 candidates, I and an undergrad mentee created a sample of 4,350 emission-line galaxies (ELGs) at redshifts 1.16

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