[PDF] Extragalactic Background Light From Hierarchical Galaxy Formation eBook

Author :
Publisher :
Page : 14 pages
File Size : 34,47 MB
Release : 2013
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ISBN :

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Here, we present a new model of the extragalactic background light (EBL) and corresponding [gamma][gamma] opacity for intergalactic gamma-ray absorption from z = 0 up to z = 10, based on a semi-analytical model of hierarchical galaxy formation that reproduces key observed properties of galaxies at various redshifts. Including the potential contribution from Population III stars and following the cosmic reionization history in a simplified way, the model is also broadly consistent with available data concerning reionization, particularly the Thomson scattering optical depth constraints from Wilkinson Microwave Anisotropy Probe (WMAP). In comparison with previous EBL studies up to z ~ 3-5, our predicted [gamma][gamma] opacity is in general agreement for observed gamma-ray energy below 400/(1 + z) GeV, whereas it is a factor of ~2 lower above this energy because of a correspondingly lower cosmic star formation rate, even though the observed ultraviolet (UV) luminosity is well reproduced by virtue of our improved treatment of dust obscuration and direct estimation of star formation rate. Moreover, the horizon energy at which the gamma-ray opacity is unity does not evolve strongly beyond z ~ 4 and approaches ~20 GeV. The contribution of Population III stars is a minor fraction of the EBL at z = 0, and is also difficult to distinguish through gamma-ray absorption in high-z objects, even at the highest levels allowed by the WMAP constraints. Nevertheless, the attenuation due to Population II stars should be observable in high-z gamma-ray sources by telescopes such as Fermi or the Cherenkov Telescope Array and provide a valuable probe of the evolving EBL in the rest-frame UV. Our detailed results of our model are publicly available in numerical form at http://www.slac.stanford.edu/~yinoue/Download.html.

Author : Houjun Mo
Publisher : Cambridge University Press
Page : 841 pages
File Size : 18,7 MB
Release : 2010-05-20
Category : Science
ISBN : 0521857937

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A coherent introduction for researchers in astronomy, particle physics, and cosmology on the formation and evolution of galaxies.

Author : William Cowley
Publisher : Springer
Page : 221 pages
File Size : 22,93 MB
Release : 2017-10-02
Category : Science
ISBN : 3319667483

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This thesis combines a theoretical model of galaxy formation with a treatment of the radiative transfer in the titular dusty star-forming galaxies. Embedding this within the well-established ΛCDM (Lambda cold dark matter) cosmology, the author was able to simulate galaxy populations from which realistic observational images were synthesised. Based on further analysis, he shows that there is a good correspondence with observations from new instruments such as the SCUBA2 bolometric camera and the Atacama Large Millimeter Array (ALMA) interferometer, and reveals some novel aspects of this exciting galaxy population. In particular, he shows that blending of these galaxies in the imaging produces an artificial enhancement in their clustering, which he dubs “blending bias”. This implies that the host dark matter halo masses for these galaxies have previously been significantly overestimated. He also presents amongst the first predictions from a galaxy formation model for observations of these galaxies that will be made by the James Webb Space Telescope (the successor to the Hubble Space Telescope).

Author : The Cta Consortium
Publisher : World Scientific
Page : 365 pages
File Size : 27,99 MB
Release : 2018-12-31
Category : Science
ISBN : 9813270101

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This book summarizes the science to be carried out by the upcoming Cherenkov Telescope Array, a major ground-based gamma-ray observatory that will be constructed over the next six to eight years. The major scientific themes, as well as core program of key science projects, have been developed by the CTA Consortium, a collaboration of scientists from many institutions worldwide.CTA will be the major facility in high-energy and very high-energy photon astronomy over the next decade and beyond. CTA will have capabilities well beyond past and present observatories. Thus, CTA's science program is expected to be rich and broad and will complement other major multiwavelength and multimessenger facilities. This book is intended to be the primary resource for the science case for CTA and it thus will be of great interest to the broader physics and astronomy communities. The electronic version (e-book) is available in open access.

Author : Volker Bromm
Publisher : Springer
Page : 240 pages
File Size : 17,59 MB
Release : 2016-09-07
Category : Science
ISBN : 9783642119644

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The formation of the first stars (Pop III stars) and galaxies is one of the great outstanding challenges in modern astrophysics and cosmology. The first stars are likely key drivers for early cosmic evolution and will be at the center of attention over the next decade. The best available space and ground-based telescopes like the Hubble Space Telescope probe the Universe to high redshifts and provide us with tantalizing hints; but they cannot yet directly detect the first generation of stars and the formation of the first galaxies. This is left as key science for future telecopes like the James Webb Space Telescope. This book is based in part on classroom tested lectures related to Pop III stars, but also draws from the author's review articles of the main physical principles involved. The book will thus combine pedagogical introductory chapters with more advanced ones to survey the cutting-edge advances from the frontier of research. It covers the theory of first star formation, the relation between first stars and dark matter, their impact on cosmology, their observational signatures, the transition to normal star formation as well as the assembly of the first galaxies. It will prepare students for interpreting observational findings and their cosmological implications.

Author : International Astronomical Union. Symposium
Publisher : Springer Science & Business Media
Page : 546 pages
File Size : 27,18 MB
Release : 1990-08-31
Category : Science
ISBN : 9780792308416

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Proceedings of the 139th Symposium of the International Astronomical Union on `The Galactic and Extragalactic Background Radiation, held in Heidelberg, FRG, June 12-16, 1989

Author : G.C. Branco
Publisher : Springer Science & Business Media
Page : 549 pages
File Size : 27,34 MB
Release : 2012-12-06
Category : Science
ISBN : 9401006768

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The NATO Advanced Study Institute 2000 was held in Cascais, a small town located in a renowned beach resort area, near Lisbon. The aim of the Meeting was to provide an overview and to cover the recent devel opments in some of the most important topics in Particle Physics and Cosmology, including Neutrino Physics, CP violation, B-Physics, Baryo genesis, Dark Matter, Inflation, Supersymmetry, Unified Theories, Large Extra-Di~ensions and M-theory. In the NATO ASI 2000, we had the priv ilege to have among the lecturers, some of the most prominent physicists working in the fields of Particle Physics and Cosmology. Furthermore, there was a strong participation by a large number of young scientists, including graduate students and post-docs who had an opportunity to learn about the latest developments in the field and discuss the various topics with lec turers and other participants. The enthusiasm of the young participants, the generosity of the lecturers in giving their time to participate in open discussions and debates, together with the social events and the pleasant environment of Cascais, all contributed to the great success of the Meeting. We are very grateful to Camara Municipal de Cascais for their support and organization of the reception in the beautiful Palace Condes Castro de Guimaraes and we are also specially grateful to colonel Eugenio de Oliveira for his support, to commander A. Monteiro de Macedo and to Mr.

Author : Claes Fransson
Publisher : World Scientific
Page : 280 pages
File Size : 15,76 MB
Release : 2001
Category : Science
ISBN : 9789812810434

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It is generally felt in the cosmology and particle astrophysics community that we have just entered an era which later can only be looked back upon as a golden age. Thanks to the rapid technical development, with powerful new telescopes and other detectors taken into operation at an impressive rate, and the accompanying advancement of theoretical ideas, the picture of the past, present and future Universe is getting ever clearer. Some of the most exciting new findings and expected future developments are discussed in this invaluable volume. The topics covered include the physics of the early Universe and ultra-high energy processes. Emphasis is also put on neutrino physics and astrophysics, with the evidence for non-zero neutrino masses emerging from both solar neutrinos and atmospheric neutrinos covered in great depth. Another field with interesting new results concerns the basic cosmological parameters, where both traditional methods and the potential of new ones, like deep supernova surveys and acoustic peak detections in the cosmic microwave background, are thoroughly discussed. Various aspects of the dark matter problem, such as gravitational lensing estimates of galaxy masses, cluster evolution and hot cluster electron distortions of the thermal microwave background spectrum, are also discussed, as are particle physics candidates of dark matter and methods to detect them. Cosmic rays of matter and antimatter are included as a topic, and so is the problem of the enigmatic dark energy of the vacuum. Contents: Cosmology with Clusters of Galaxies (N A Bahcall); Radiochemical Solar Neutrino Experiments and Implications (T A Kirsten); Evidence for Neutrino Oscillation Observed in Super-Kamiokande (Y Totsuka); High Energy Cosmic Neutrinos (S W Barwick); Discovery of the Cosmic Microwave Background (D T Wilkinson & P J E Peebles); Starlight in the Universe (P Madau); Acceleration of Ultra High Energy Cosmic Rays (R D Blandford); Dark Matter and Dark Energy in the Universe (M S Turner); Dark Matter Tomography (J A Tyson); Status of Models for Gamma Ray Bursts (M J Rees); and other papers. Readership: High energy physicists, astrophysicists and cosmologists.