Download or read book The Large Scale Distribution and Photometric Properties of Galaxies Centered on the Hubble Deep Field written by Jennifer Elizabeth Parker and published by . This book was released on 1999 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Hubble Deep Field written by Space Telescope Science Institute (U.S.). Symposium and published by Cambridge University Press. This book was released on 1998-10-13 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Hubble Deep Field (HDF) is the deepest optical image of the Universe ever obtained. It is the result of a 150-orbit observing programme with the Hubble Space Telescope. It provides a unique resource for researchers studying the formation and evolution of stars and galaxies. This timely volume provides the first comprehensive overview of the HDF and its scientific impact on our understanding in cosmology. It presents articles by a host of world experts who gathered together at an international conference at the Space Telescope Science Institute. The contributions combine observations of the HDF at a variety of wavelengths with the latest theoretical progress in our understanding of the cosmic history of star and galaxy formation. The HDF is set to revolutionize our understanding in cosmology. This book therefore provides an indispensable reference for all graduate students and researchers in observational or theoretical cosmology.

Download or read book Resolved KPC scale Properties of Emission line Galaxies at Intermediate Redshifts written by Shoubaneh Hemmati and published by . This book was released on 2015 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: The focus of this dissertation is to study resolved substructures in galaxies at kpc-scale and their relation with the global properties of the host galaxy using combined high resolution photometric data from the Hubble Space Telescope and very deep long exposure spectroscopic observations with the Keck telescopes. I use the optical and near-infrared data taken as part of the CANDELS project to perform pixel-by-pixel analysis of 120 galaxies at intermediate redshifts. I produce resolved rest-frame (U-V) color, stellar mass and star formation rate surface densities, stellar age and extinction maps and profiles along the galaxies rotation axes. I study physical properties of clumps and quantify their spatial distribution and covering fraction. Investigating the evolution of covering fraction and average radial distance with respect to both redshift and stellar mass of the host galaxy, suggests that if the central bulge growth is due to migration of stellar clumps, it should have happened at higher redshifts. I find that there exists a tight correlation between the stellar mass and star formation rate surface densities of pixels inside individual galaxies as well as among red and blue clumps over different galaxies. The tightness of the blue clumps main sequence regardless of the large redshift rang of the hosts, suggests no evolution in the nature of blue clumps with time. I estimate small-scale distribution of stellar dust extinction from pixel-by-pixel SED fitting and used H[Alpha]/ H[Beta] nebular emission line ratios from Keck/DEIMOS spectra at each spatial resolution element to measure attenuation faced by ionized gas at different radii from the center of galaxies. I find a good agreement between the integrated and median of resolved color excess measurements in the galaxies. I find that inclination plays an important role in the variation of the nebular to stellar color excess ratio. I find that the nebular color excess increases with stellar mass surface density. This explains the absence of radial trend in the nebular color excess in lower mass galaxies. I also demonstrate the usefulness of resolved optical line ratio plots in identifying otherwise hidden AGNs.

Download or read book Studying Distant Galaxies A Handbook Of Methods And Analyses written by Francois Hammer and published by World Scientific Publishing Company. This book was released on 2016-11-15 with total page 399 pages. Available in PDF, EPUB and Kindle. Book excerpt: Distant galaxies encapsulate the various stages of galaxy evolution and formation from over 95% of the development of the universe. As early as twenty-five years ago, little was known about them, however since the first systematic survey was completed in the 1990s, increasing amounts of resources have been devoted to their discovery and research. This book summarises for the first time the numerous techniques used for observing, analysing, and understanding the evolution and formation of these distant galaxies.In this rapidly expanding research field, this text is an every-day companion handbook for graduate students and active researchers. It provides guidelines in sample selection, imaging, integrated spectroscopy and 3D spectroscopy, which help to avoid the numerous pitfalls of observational and analysis techniques in use in extragalactic astronomy. It also paves the way for establishing relations between fundamental properties of distant galaxies. At each step, the reader is assisted with numerous practical examples and ready-to-use methodology to help understand and analyse research.François Hammer worked initially in general relativity and made the first modelling of gravitational lenses prior to their spectroscopic confirmation. Following this, he became co-leader of the first complete survey of distant galaxies, the Canada-France-Redshift Survey. This led to the discovery of the strong decrease of the cosmic star formation density measured from UV light as z=1, which, alongside Hector Flores, they confirmed as bolometric and dust independent. With Mathieu Puech, they then pioneered the 3D spectroscopy of distant galaxies, leading to a major increase of understanding of the dynamic state of distant galaxies evidenced by the scatter of the Tully-Fisher relation. This led them to propose, with the addition to the team of Myriam Rodrigues, that galactic disks may survive or be rebuilt in gas-rich mergers, a scenario that is consistent with contemporary cosmological simulations. Besides extensive observational experience, the authors have led, or are leading, several instruments implemented or to be implemented at the largest telescopes, including VLT/Giraffe, VLT/X-shooter, VLT/MOONS and E-ELT/MOSAIC. They have also developed several observational techniques in adaptive optics, and in sky subtraction for integral field units and fibre instruments.

Download or read book Geometrical properties of the large scale distribution of galaxies written by Maren Hauschildt and published by . This book was released on 1985 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Multiwavelength Atlas of Galaxies written by Glen Mackie and published by Cambridge University Press. This book was released on 2011-01-06 with total page 269 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the radio signature of our own Milky Way was detected in 1931, galaxies have been observed from ultra-high energy gamma rays to long wavelength radio waves, providing fundamental insights into their formation, evolution and structural components. Unveiling the secrets of some of the best-observed galaxies, this atlas contains over 250 full-color images spanning the whole electromagnetic spectrum. The accompanying text explains why we see the component stars, gas and dust through different radiation processes, and describes the telescopes and instruments used. This atlas is a valuable reference resource on galaxies for students seeking an overview of multiwavelength observations and what they tell us, and researchers needing detailed summaries of individual galaxies. An accompanying website, hosted by the author, contains slide shows of the galaxies covered in the book. This is available at www.cambridge.org/9780521620628.

Download or read book The Galaxies of the Local Group written by Sidney Bergh and published by Cambridge University Press. This book was released on 2000-05-15 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Local Group is a small cluster of galaxies that includes the Milky Way. At least half of all galaxies in the Universe are thought to belong to similar groups. This authoritative volume provides a comprehensive synthesis of what is known about the Local Group. It begins with a summary of each member galaxy, as well as those galaxies previously regarded as possible members. The book examines the mass, stability and evolution of the Local Group as a whole and includes many important previously unpublished results and conclusions. With clarity, Professor van den Bergh provides a masterful summary of all that is known about the galaxies of the Local Group and their evolution, and expertly places this knowledge in the wider context of on-going studies of galaxy formation and evolution, the cosmic distance scale, and the conditions in the early Universe.

Download or read book The Evolution of Galaxies in the Hubble Deep Fields written by Stephen Donald Jermy Gwyn and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis is a study of several aspects of the evolution of galaxies using photometric redshifts in the Hubble Deep Fields (HDF's). The photometric redshift method is used in the HDF's down to a magnitude limit of I = 28. The large sample and the unprecedented depth of the Hubble Deep Fields allow one to trace the evolution of several properties of galaxies from z = 5 to the present in a statistical manner. This thesis studies four such aspects: (1) The clustering of galaxies is examined. When the redshift distributions of the HDF-North and the HDF-South are compared, one finds a significantly greater number of galaxies around z = 0.5. This suggests the presence of a structure (a very weak cluster or a very strong group) in the HDF-North. (2) The star formation rate density (SFRD) is determined by measuring the UV-luminosity density. After correcting for dust extinction, the star formation rate is found to decrease exponentially with time with an e-folding period of about 4 Gyr. (3) The difference between the rate of declines of the B band galaxy number density and the luminosity densities are used to examine the merging history of the Universe. While the total B band luminosity density of the Universe decreases only slightly with time since z = 5, the number density of galaxies drops considerably more. On average, a present day galaxy is the product of ∼3 progenitors. (4) The morphology of galaxies is quantified using a "lumpiness" parameter, L, which measures the number of local maxima in the image of a galaxy. Rest-frame B band images are made of both HDF's by k-correcting each pixel of each galaxy in the frames using the photometric redshifts of the parent galaxies. It is found that L increases with increasing absolute brightness and increasing redshift, albeit only slightly.

Download or read book Geometrical Properties of the Large Scale Distribution of Galaxies with Special Consideration of the Perseus Supercluster written by Maren Hauschildt and published by . This book was released on 1986 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Unveiling Galaxies written by Jean-René Roy and published by Cambridge University Press. This book was released on 2018 with total page 311 pages. Available in PDF, EPUB and Kindle. Book excerpt: A thought provoking study of the powerful impact of images in guiding astronomers' understanding of galaxies through time.

Download or read book Galaxies and Cosmology written by F. Combes and published by Springer. This book was released on 1995 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt: Unique in its breadth of coverage and level of presentation, this textbook examines the nature of galaxies, extragalactic objects, the large-scale structure of the Universe, and cosmology more closely than general textbooks on astronomy, while still remaining comprehensible for advanced undergraduate students. One or several chapters are devoted to the following: the formation, classification and morphology of galaxies; the interactions between galaxies; the galactic interstellar medium; galactic kinematics; elliptical, spiral, and barred spiral galaxies; extragalactic radio sources, quasars, their line spectra, and other active galactic nuclei; the Universe as a whole.

Download or read book Assessment of Options for Extending the Life of the Hubble Space Telescope written by National Research Council and published by National Academies Press. This book was released on 2005-03-28 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Hubble Space Telescope (HST) has operated continuously since 1990. During that time, four space shuttle-based service missions were launched, three of which added major observational capabilities. A fifth â€" SM-4 â€" was intended to replace key telescope systems and install two new instruments. The loss of the space shuttle Columbia, however, resulted in a decision by NASA not to pursue the SM-4 mission leading to a likely end of Hubble's useful life in 2007-2008. This situation resulted in an unprecedented outcry from scientists and the public. As a result, NASA began to explore and develop a robotic servicing mission; and Congress directed NASA to request a study from the National Research Council (NRC) of the robotic and shuttle servicing options for extending the life of Hubble. This report presents an assessment of those two options. It provides an examination of the contributions made by Hubble and those likely as the result of a servicing mission, and a comparative analysis of the potential risk of the two options for servicing Hubble. The study concludes that the Shuttle option would be the most effective one for prolonging Hubble's productive life.

Download or read book The Large Scale Characteristics of the Galaxy written by W.B. Burton and published by Springer. This book was released on 2011-11-05 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt: The International Astronomical Union has encouraged the study of our galaxy through a series of symposia. This volume contains the proceedings of IAU Symposium No. 84 on the Large-Scale Characteristics of the Galaxy, held in College Park, Maryland, from June 12 to 17, 1978. Symposium No. 84 was jointly sponsored by IAU 2ommission 33, Structure and Dynamics of the Galactic System, and by Commission 34, Interstellar Matter and Planetary Nebulae. The Scientific Organizing Committee consisted of F. J. Kerr (chairman), B. J. Bok, W. B. Burton, J. Einasto, K. C. Freeman, P. O. Lindblad, D. Lynden-Bell, R. Sancisi, S. E. Strom, H. van Woerden, and R. Wielen. The topics and speakers were chosen in order to emphasize current observational material and theoretical results pertaining to various morphological aspects of our galaxy. In preparing the program particular care was taken to relate recent work on other galaxies to the situation in our own galaxy. The meetings were held in the Center for Adult Education on the campus of the University of Maryland. The Local Organizing Committee consisted of B. M .. Zuckerman (chairman), A. P. Henderson, P. D. Jackson, T. A. Matthews, B. F. Perry, V. C. Rubin, P. R. Schwartz, F. W. Stecker, J. D. Trasco, and G. Westerhout. Joan Ball ably assisted this committee. The National Science Foundation made a financial con tribution to the general support of the meeting. The National Radio Astronomy Observatory assisted with some of the participants' travel expenses.

Download or read book Models of the Distribution of Photometric Properties of Galaxies with Star Formation written by and published by . This book was released on 1979 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Tidal Streams in the Local Group and Beyond written by Heidi Jo Newberg and published by Springer. This book was released on 2018-03-30 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume is written by leading scientists in the field, who review the current state of our knowledge of tidal streams in the Milky Way, the Andromeda galaxy, and in other nearby galaxies. The cosmological origins of dwarf galaxies and the physical processes by which they are tidally disrupted into streams and incorporated into galaxy halos are discussed. The techniques that have been used to identify tidal streams are presented and will be useful to researchers who would like to find substructures in the next generation of optical sky surveys, including Pan-STARRS and LSST. The methods that are currently under development to constrain both large scale distribution of dark matter in the Milky Way and the (small scale) lumpiness of the dark matter distribution are also explained. The authors also provide motivation for future spectroscopic surveys of Milky Way halo stars, which will aid both in the identification of tidal streams and the constraint of dark matter properties. This volume is aimed at graduate students who are beginning this field of research, but is also a resource for researchers who study tidal streams and related fields. In addition to presenting the physical processes by which tidal streams are created, it also reviews the current state of the observations and the progress towards utilizing these observations to constrain the distribution of dark matter in the Milky Way. The book will introduce anyone with a background in astrophysics to the field of tidal streams.

Download or read book The Universe at Moderate Redshift written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2019-01-03 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: The report covers the work done in the past year and a wide range of fields including properties of clusters of galaxies; topological properties of galaxy distributions in terms of galaxy types; patterns of gravitational nonlinear clustering process; development of a ray tracing algorithm to study the gravitational lensing phenomenon by galaxies, clusters and large-scale structure, one of whose applications being the effects of weak gravitational lensing by large-scale structure on the determination of q(0); the origin of magnetic fields on the galactic and cluster scales; the topological properties of Ly(alpha) clouds the Ly(alpha) optical depth distribution; clustering properties of Ly(alpha) clouds; and a determination (lower bound) of Omega(b) based on the observed Ly(alpha) forest flux distribution. In the coming year, we plan to continue the investigation of Ly(alpha) clouds using larger dynamic range (about a factor of two) and better simulations (with more input physics included) than what we have now. We will study the properties of galaxies on 1 - 100h(sup -1) Mpc scales using our state-of-the-art large scale galaxy formation simulations of various cosmological models, which will have a resolution about a factor of 5 (in each dimension) better than our current, best simulations. We will plan to study the properties of X-ray clusters using unprecedented, very high dynamic range (20,000) simulations which will enable us to resolve the cores of clusters while keeping the simulation volume sufficiently large to ensure a statistically fair sample of the objects of interest. The details of the last year's works are now described. Cen, Renyue and Ostriker, Jeremiah P. Goddard Space Flight Center NASA-CR-205473, NAS 1.26:205473 NAG5-2759...

Download or read book International Aerospace Abstracts written by and published by . This book was released on 1999 with total page 974 pages. Available in PDF, EPUB and Kindle. Book excerpt: