Download or read book Extending the Realm of Galaxies to the Low Surface Brightness Universe written by Brisa Mancillas Vaquera and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The exploration of diffuse light emission and the outskirts of galaxies in the regime of the Low Surface Brightness (LSB) is of utmost importance to understand the formation mechanism of galaxy evolution, and is essential to constrain the current theoretical models and numerical simulations in the cosmological context. Observational data, both in optical and radio emission, complemented with hydrodynamical cosmological numerical simulations provide us a crucial information about the morphological properties of substructures surrounding massive galaxies, as well as the mass distribution, molecular gas content and star formation of LSB galaxies such as the recently discovered Ultra Diffuse Galaxies (UDGs).This thesis presents several analysis addressed to the study of these schemes. In first instance, motivated in the most recent works about optimized deep imaging surveys observed with the CFHT telescope, which have revealed prominent LSB fine structures classified like tidal tails, stellar streams and shells, we have computed statistics of an hydrodynamical numerical simulation in order to interpret observations and make inferences about the past mass assembly of galaxies. We made a census of these substructures and computed their survival time. We also studied their dependence with several properties like the projection and the surface brightness. We found that shells and streams remains visible around 4 Gyr and they are mainly associated to minor mergers and a continuous diffuse gas accretion, while tidal tails have a durability time of around 1 Gyr and are correlated with major merger events. In parallel, in this work we made use of a semi-empirical approach to build-up a mock catalog with the aim to make predictions about scaling relations and constrain physical parameters of UDGs and LSB galaxies.On the other hand, we have performed CO spectroscopy surveys of UDGs observed at IRAM-30m to quantify the molecular gas content. The selected galaxies were conformed by sources from several environments and different properties, including objects like the very red galaxies Dragonfly 44 and DGSAT I. We have obtained unprecedented upper limits of their CO mass (few 10^6 - 10^7 solar masses). We also made CO observations at IRAM-30m to detect molecular gas content in a sample of four early-type galaxies that exhibit prominent shell galaxies like the case of NGC 0474 and Arp 230. Our goal is to test the phase wrapping formation model proposed in numerical simulations. We detected a molecular mass of around 10^8 solar masses in several shells of one galaxy of our sample and we report the mass upper limits for the other cases.

Download or read book Images of Low Surface Brightness Galaxies written by and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Greg Bothun presents a collection of images of low surface brightness galaxies, as part of the Electronic Universe resource. The resource includes a detailed reference list about the galaxies. Each image features a summary of details on the galaxies.

Download or read book The Low Surface Brightness Universe written by Jonathan I. Davies and published by . This book was released on 1999 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Outskirts of Galaxies written by Johan H. Knapen and published by Springer. This book was released on 2017-07-09 with total page 367 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book consists of invited reviews written by world-renowned experts on the subject of the outskirts of galaxies, an upcoming field which has been understudied so far. These regions are faint and hard to observe, yet hide a tremendous amount of information on the origin and early evolution of galaxies. They thus allow astronomers to address some of the most topical problems, such as gaseous and satellite accretion, radial migration, and merging. The book is published in conjunction with the celebration of the end of the four-year DAGAL project, an EU-funded initial training network, and with a major international conference on the topic held in March 2016 in Toledo. It thus reflects not only the views of the experts, but also the scientific discussions and progress achieved during the project and the meeting. The reviews in the book describe the most modern observations of the outer regions of our own Galaxy, and of galaxies in the local and high-redshift Universe. They tackle disks, haloes, streams, and accretion as observed through deep imaging and spectroscopy, and guide the reader through the various formation and evolution scenarios for galaxies. The reviews focus on the major open questions in the field, and explore how they can be tackled in the future. This book provides a unique entry point into the field for graduate students and non-specialists, and serves as a reference work for researchers in this exciting new field.

Download or read book Globular Cluster Systems written by Keith M. Ashman and published by Cambridge University Press. This book was released on 2008-12-11 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: Globular clusters are roughly spherical, densely packed groups of stars found around galaxies. Most globular clusters probably formed at the same time as their host galaxies. Therefore they provide a unique fossil record of the conditions during the formation and early evolution of galaxies. This volume presents a comprehensive review of globular cluster systems. It summarizes their observed properties and shows how these constrain models of the structure of stars, the formation and evolution of galaxies and globular clusters, and the age of the Universe. For graduate students and researchers, this timely volume provides the definitive reference on globular cluster systems.

Download or read book A Philosophical Approach to MOND written by David Merritt and published by Cambridge University Press. This book was released on 2020-04-30 with total page 285 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dark matter is a fundamental component of the standard cosmological model, but in spite of four decades of increasingly sensitive searches, no-one has yet detected a single dark-matter particle in the laboratory. An alternative cosmological paradigm exists: MOND (Modified Newtonian Dynamics). Observations explained in the standard model by postulating dark matter are described in MOND by proposing a modification of Newton's laws of motion. Both MOND and the standard model have had successes and failures – but only MOND has repeatedly predicted observational facts in advance of their discovery. In this volume, David Merritt outlines why such predictions are considered by many philosophers of science to be the 'gold standard' when it comes to judging a theory's validity. In a world where the standard model receives most attention, the author applies criteria from the philosophy of science to assess, in a systematic way, the viability of this alternative cosmological paradigm.

Download or read book The low surface brightness universe IAU Colloquium 171 proceedings of an IAU Colloquium held at Cardiff Wales 5 10 July 1998 written by Jon I. Davies and published by . This book was released on 1999 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dark Matter in the Darkest Galaxies written by Jaya Nagarajan-Swenson and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dark matter in our universe is not evenly distributed: some galaxies are lacking it entirely, and some galaxies have it in abundance. While its existence is generally agreed on, its distribution within galaxies is hotly debated. Low Surface Brightness (LSB) spirals are a class of galaxy with peculiarly low star-formation rates, and one possible explanation for this points to an overabundance of dark matter relative to normal (baryonic) matter. LSB spirals tend to be dark matter-dominated at all radii, which makes them an ideal place to probe the structure of galactic dark matter haloes. In contrast, “normal” High Surface Brightness (HSB) spirals are baryon-dominated at the core, which obscures the central structure and muddles the apparent mass distribution of the galaxy. Currently, LSB spirals appear to be compatible with a “cored” halo, possibly due to early central star formation driving baryons out of the center, which dragged dark matter out along with it, thereby transforming a cuspy halo into a cored one. This thesis explores both the mystery of LSB spirals and the mystery of dark matter, pairing them together to shed light on the evolutionary difference between LSB and HSB spiral galaxies and begin examining cusp-core transformation. Optical emission line-derived velocity fields are used to determine the dynamical mass at different radii in a sample of eight LSB spirals, and archival Spitzer IRAC images allow the stellar mass at different radii in these galaxies to be determined. This results in a robust estimation of the structure of each galaxy's dark matter halo. We conclude that LSB spirals indeed tend to be dark matter-dominated at all radii, and highlight UGC 4179 as a likely case of solid-body rotation. Additionally, a peculiar trend in the [OII] to [OIII] ratio in these spectra is apparent, possibly supporting the truncated IMF hypothesis to explain LSB spirals.

Download or read book Galaxies in the Local Volume written by Bärbel Silvia Koribalski and published by Springer Science & Business Media. This book was released on 2009-04-29 with total page 375 pages. Available in PDF, EPUB and Kindle. Book excerpt: This timely book presents an overview of the galaxies within the Local Volume, including the Local Group and our closest neighbours, the Andromeda Galaxy and the Magellanic Clouds. Presented here are the latest results from radio, infrared and optical surveys as well as detailed multi-wavelength studies of individual galaxies. The book aims to provide a vibrant forum for presentations and discussions across a broad range of astrophysical topics.

Download or read book Galaxy Morphology written by B. W. Holwerda and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Galaxy morphology is a long-standing subfield of astronomy, moving from visual qualifications to quantitative morphometrics. This book covers the descriptions developed by astronomers to describe the appearance of galaxies, primarily in optical, ultraviolet and near-infrared wavelengths.

Download or read book Unsolved Problems of the Milky Way written by International Astronomical Union. Symposium and published by Springer. This book was released on 1996-06-30 with total page 778 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the 169th Symposium of the International Astronomical Union, held in The Hague, the Netherlands, August 23-29, 1994

Download or read book The Nature of Ultra low Surface Brightness Objects written by Julianne Dalcanton and published by . This book was released on 1995 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Atomic Hydrogen in the Local Universe written by Martin Alexander Zwaan and published by . This book was released on 2000 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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.

Download or read book Fundamentals of Galaxy Dynamics Formation and Evolution written by Ignacio Ferreras and published by UCL Press. This book was released on 2019-04-02 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: Galaxies, along with their underlying dark matter halos, constitute the building blocks of structure in the Universe. Of all fundamental forces, gravity is the dominant one that drives the evolution of structures from small density seeds at early times to the galaxies we see today. The interactions among myriads of stars, or dark matter particles, in a gravitating structure produce a system with fascinating connotations to thermodynamics, with some analogies and some fundamental differences. Ignacio Ferreras presents a concise introduction to extragalactic astrophysics, with emphasis on stellar dynamics, and the growth of density fluctuations in an expanding Universe. Additional chapters are devoted to smaller systems (stellar clusters) and larger ones (galaxy clusters). Fundamentals of Galaxy Dynamics, Formation and Evolution is written for advanced undergraduates and beginning postgraduate students, providing a useful tool to get up to speed in a starting research career. Some of the derivations for the most important results are presented in detail to enable students appreciate the beauty of maths as a tool to understand the workings of galaxies. Each chapter includes a set of problems to help the student advance with the material.

Download or read book The Realm of the Nebulae written by Edwin Powell Hubble and published by Yale University Press. This book was released on 1982-01-01 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: No modern astronomer made a more profound contribution to our understanding of the cosmos than did Edwin Hubble, who first conclusively demonstrated that the universe is expanding. Basing his theory on the observation of the change in distanct galaxies, called red shift, Hubble showed that this is a Doppler effect, or alteration in the wavelength of light, resulting from the rapid motion of celestial objects away from Earth. In 1935, Hubble described his principal observations and conclusions in the Silliman lectures at Yale University. These lectures were published the following year as "The Realm of the Nebulae," which quickly became a classic work.

Download or read book Quasars Redshifts and Controversies written by Halton C. Arp and published by Cambridge University Press. This book was released on 1988-09-29 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: Contests the 'establishment' view of quasars as the most distant objects in the universe.