Download or read book Physical and Chemical Properties of Galaxies with Star Formation in Different Environments written by Salvador Duarte Puertas and published by . This book was released on 2020 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Influence of Environment on the Star Formation Properties of Galaxies written by Bruno Rodríguez Del Pino and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Stellar Content and Star Formation Rates of Dwarf Irregular Galaxies written by Jacqueline Michelle Dunn and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The star formation histories and evolution of 70 dwarf irregular galaxies that reside in differing local and global environments are investigated. Local environment is defined by the local galaxy number density, where high indicates at least one neighbor within 200 kpc and low indicates no neighbors within 1 Mpc. Global environment is classified as either the field or a galaxy group / cluster. The shallow gravitational potentials of these galaxies are more susceptible to changes in morphology and dynamics by external perturbations, making dwarf irregular galaxies ideal candidates for a study on the role of environment in galaxy evolution. Absolute magnitudes, colors, central surface brightnesses, and star formation rates were compared using UBVRIJHK and Halpha photometry. With a high degree of statistical significance, galaxies in local high density environments have brighter central and effective surface brightnesses, while those in global high density environments have brighter absolute magnitudes, central and effective surface brightnesses, and higher star formation rates. However, no difference is seen among the different environments when considering star formation rates normalized by HI mass. Sersic profiles were fit to the V and R band surface brightness profiles of the galaxies. No correlation exists between structural characteristics and environment. Spectral energy distribution models were generated by varying the rate of stellar formation and amplitude to replicate periodic burst and constant star formation rate scenarios. Of the 28 galaxies for which star formation history analysis was performed, roughly half were well fit by one of the models. Periodic burst systems account for roughly half of those galaxies, with the remaining galaxies being better represented by continuously star forming systems. The star formation histories are uncorrelated with both local and global environmental classifications. Numerical simulations provide insight into the effects of differing gravitational environments, and indicate global environment having a larger influence on the physical properties of a dwarf galaxy. The star formation histories and structural properties of dwarf irregular galaxies were found to be independent of environment, indicating that cluster membership and proximity to a neighboring galaxy have no systematic long-term effects on the evolution of the objects in this study.
Download or read book The Environment and Evolution of Galaxies written by J.M. Shull and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 597 pages. Available in PDF, EPUB and Kindle. Book excerpt: In July 1992, over 300 astronomers attended the Third Tetons Summer School on the subject of `The Environment and Evolution of Galaxies'. This book presents 28 papers based on invited review talks and a panel discussion on `The Nature of High Redshift Objects'. The major themes include: the Interstellar and Intergalactic Medium, Galaxy Formation and Evolution, Cooling Flows, Quasars and Radiation Backgrounds, and Interactions between Galaxies/AGNs and their Environment. Recent advances with the ROSAT, COBE and Hubble Space Telescope are discussed, together with current theoretical developments. The tutorial nature of the papers make this book a valuable supplement for professional astonomers, graduate students, and senior undergraduates. As with previous Tetons conferences, this book provides both the current state of observational and theoretical research and material complementary to courses in extragalactic and interstellar astrophysics.
Download or read book Physical and Chemical Properties During High mass Star Formation written by Caroline Gieser and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Probing the Environments of Star Formation Using Star Clusters in Nearby Galaxies written by Jordan A. Turner and published by . This book was released on 2021 with total page 113 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the hierarchical view of star formation, the densest regions of the interstellar medium (ISM) undergo gravitational collapse to form stars. Typically, many stars are formed in tandem to produce a star cluster. In turn, these star clusters are grouped together to form larger associations of clusters and these form together to shape the large-scale galactic structures like spiral arms. Charting the connection between the star formation at small-scales and the large-scale galactic properties is crucial for understanding the evolution of galaxies. We begin this dissertation in Chapter 1 with an introduction to the current understanding of star formation, the cold gas of the ISM, and how the two are related. We also outline the big-picture questions we seek to answer in this dissertation and the tools needed in these studies. In Chapter 2, we discuss the first step in a joint analysis of Hubble Space Telescope (HST) observations and Atacama Large Millimeter/submillimeter Array (ALMA) dust continuum maps. This study aims to correlate the emission from young star clusters with the properties of the observed dust. Chapter 3 sets up the spectral energy distribution modeling effort for the Physics at High Angular Resolutions in Nearby GalaxieS-HST (PHANGS-HST) star cluster data pipeline. This chapter goes into great detail on testing, validating, and characterizing how well we can model the star clusters. This modeling provides estimates of the physical properties of the star clusters which are critical for the analysis presented in Chapter 4. In this study, we utilize the PHANGS-HST star cluster catalogs in 11 nearby galaxies combined with the PHANGS--ALMA giant molecular cloud (GMC) catalogs in order to spatially correlate the star clusters with their natal gas clouds. With this correlation, we constrain the timescale for dissipation of the GMCs after the onset of star formation.
Download or read book Mapping the Dynamics Star formation Rates and Chemical Properties of Galaxies with Integral Field Spectroscopy written by and published by . This book was released on 2005 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Environment and Evolution of Galaxies written by J.M. Shull and published by Springer Science & Business Media. This book was released on 1993-10-31 with total page 608 pages. Available in PDF, EPUB and Kindle. Book excerpt: In July 1992, over 300 astronomers attended the Third Tetons Summer School on the subject of `The Environment and Evolution of Galaxies'. This book presents 28 papers based on invited review talks and a panel discussion on `The Nature of High Redshift Objects'. The major themes include: the Interstellar and Intergalactic Medium, Galaxy Formation and Evolution, Cooling Flows, Quasars and Radiation Backgrounds, and Interactions between Galaxies/AGNs and their Environment. Recent advances with the ROSAT, COBE and Hubble Space Telescope are discussed, together with current theoretical developments. The tutorial nature of the papers make this book a valuable supplement for professional astonomers, graduate students, and senior undergraduates. As with previous Tetons conferences, this book provides both the current state of observational and theoretical research and material complementary to courses in extragalactic and interstellar astrophysics.
Download or read book Star Formation and Galaxy Evolution in Different Environments from the Field to Massive Clusters written by Krystal Tyler and published by . This book was released on 2012 with total page 191 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigating the Impact of Group Environment on Galaxy Properties written by Stephania Barsanti and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The properties of galaxies, such as their shape and star formation rate (SFR), correclate strongly with the galaxy number density in the surrounding Universe. This is well known for cluster galaxies, which show a suppression of the star formation activity with respect to the field, but the situation is less clear for groups. The aim of this research is to explore whether and how the group environment may affectthe star formation properties of infalling star-forming galaxies. We use the Galaxy And Mass Assembly (GAMA) group catalogue, finding that the specific SFR of star-forming members declines at ~ 3.5 R200 towards the group centre by a factor ~ 1.3 with respect to field galaxies. We explore the use of the projected phase space (PPS) diagram, i.e. the galaxy velocity as a function of projected group-centric radius, as an environment metric in the group mass regime. The PPS has been extensively used for investigating more massive clusters where the position of a galaxy in the PPS correlates with time since infall. Similar to cluster studies, we find that the fraction of star-forming group galaxies is higher in the PPS regions dominated by recently accreted galaxies, whereas passive galaxies dominate the virialised regions.
Download or read book Resolved Studies of the Dynamics Star Formation and Chemical Properties of High redshift Galaxies written by Steven Richard Gillman and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Planets Stars and Stellar Systems written by William C Keel and published by Springer. This book was released on 2013-02-27 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is volume 6 of Planets, Stars and Stellar Systems, a six-volume compendium of modern astronomical research, covering subjects of key interest to the main fields of contemporary astronomy. This volume on “Extragalactic Astronomy and Cosmology” edited by William C. Keel presents accessible review chapters on Galaxy Morphology, Elliptical and Disk Galaxy Structure and Modern Scaling Laws, Star Formation in Galaxies, The Cool ISM in Galaxies, The Influence of Environment on Galaxy Evolution, Clusters of Galaxies, Active Galactic Nuclei, Large Scale Structure of the Universe, Distance Scale of the Universe, Galaxies in the Cosmological Context, Evolution of Active Galactic Nuclei, The Intergalactic Medium, and Cosmic Microwave Background. All chapters of the handbook were written by practicing professionals. They include sufficient background material and references to the current literature to allow readers to learn enough about a specialty within astronomy, astrophysics and cosmology to get started on their own practical research projects. In the spirit of the series Stars and Stellar Systems published by Chicago University Press in the 1960s and 1970s, each chapter of Planets, Stars and Stellar Systems can stand on its own as a fundamental review of its respective sub-discipline, and each volume can be used as a textbook or recommended reference work for advanced undergraduate or postgraduate courses. Advanced students and professional astronomers in their roles as both lecturers and researchers will welcome Planets, Stars and Stellar Systems as a comprehensive and pedagogical reference work on astronomy, astrophysics and cosmology.
Download or read book Formation of Stars and Star Clusters in Colliding Galaxies written by Pierre-Emmanuel Aime Marcel Belles 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 Soil and Environmental Chemistry written by William F. Bleam and published by Academic Press. This book was released on 2016-11-30 with total page 592 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soil and Environmental Chemistry, Second Edition, presents key aspects of soil chemistry in environmental science, including dose responses, risk characterization, and practical applications of calculations using spreadsheets. The book offers a holistic, practical approach to the application of environmental chemistry to soil science and is designed to equip the reader with the chemistry knowledge and problem-solving skills necessary to validate and interpret data. This updated edition features significantly revised chapters, averaging almost a 50% revision overall, including some reordering of chapters. All new problem sets and solutions are found at the end of each chapter, and linked to a companion site that reflects advances in the field, including expanded coverage of such topics as sample collection, soil moisture, soil carbon cycle models, water chemistry simulation, alkalinity, and redox reactions. There is also additional pedagogy, including key term and real-world scenarios. This book is a must-have reference for researchers and practitioners in environmental and soil sciences, as well as intermediate and advanced students in soil science and/or environmental chemistry. Includes additional pedagogy, such as key terms and real-world scenarios Supplemented by over 100 spreadsheets to migrate readers from calculator-based to spreadsheet-based problem-solving that are directly linked from the text Includes example problems and solutions to enhance understanding Significantly revised chapters link to a companion site that reflects advances in the field, including expanded coverage of such topics as sample collection, soil moisture, soil carbon cycle models, water chemistry simulation, alkalinity, and redox reactions
Download or read book Galaxy Formation and Evolution written by Houjun Mo and published by Cambridge University Press. This book was released on 2010-05-20 with total page 841 pages. Available in PDF, EPUB and Kindle. Book excerpt: A coherent introduction for researchers in astronomy, particle physics, and cosmology on the formation and evolution of galaxies.
