Author: Matthias Bartelmann
Publisher:
ISBN:
Category :
Languages : en
Pages : 18

Get Book Here

Book Description

Author: Halton C. Arp
Publisher: Cambridge University Press
ISBN: 9780521363143
Category : Science
Languages : en
Pages : 220

Get Book Here

Book Description
Contests the 'establishment' view of quasars as the most distant objects in the universe.

Author: Emily P. Wang
Publisher:
ISBN:
Category :
Languages : en
Pages : 68

Get Book Here

Book Description
In this thesis, I studied the lensed quasar CX2201-3201, which is lensed by an edge-on spiral galaxy. The unusually high tilt of the spiral galaxy provides us with a rare opportunity for mass modeling. In addition, the unusual placement of the two visible images of the system offers an intriguing lensing system for study-the two images straddle the lensing galaxy's visible disk, but are off to one side of the light centroid. Based on mass models for the lens that are constrained by the visible disk of the galaxy, the quadrupole of the disk is strong enough to make CX2201 a "naked cusp" system, which should have three images-the two images we see, plus another located in the disk of the galaxy. We attempt to explain the absence of the third "naked cusp" image by using a series of increasingly exotic mass models. Unfortunately, none of these models turn out to be both satisfactory and a feasible solution. Although we are unable to answer the question of why the two images of CX2201 are located off to the side of the lensing galaxy's center, we gain a better understanding of the challenges this system poses for those attempting to model the lensing galaxy's mass. HST data has been obtained for the system, and although this data were obtained too late for proper inclusion in this thesis, they may aid future investigators in analyzing CX2201. Plans to obtain detailed rotation curves for the lensing galaxy are also underway, and it is the hope that future investigators will come to a better understanding of CX2201's unique features.

Author: Halton C. Arp
Publisher: Apeiron
ISBN:
Category : Science
Languages : en
Pages : 326

Get Book Here

Book Description

Author: Daniel W. Weedman
Publisher: Cambridge University Press
ISBN: 9780521356749
Category : Science
Languages : en
Pages : 236

Get Book Here

Book Description
A current account of quasar astronomy that not only summarizes existing results from various techniques but refers to the potentialities of new instruments. All aspects of quasar spectroscopy are discussed and techniques for analyzing quasar data are summarized.

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 25

Get Book Here

Book Description
We report the discovery of five gravitationally lensed quasars from the Sloan Digital Sky Survey (SDSS). All five systems are selected as two-image lensed quasar candidates from a sample of high-redshift (z> 2.2) SDSS quasars. We confirmed their lensing nature with additional imaging and spectroscopic observations. The new systems are SDSS J0819+5356 (source redshift z{sub s} = 2.237, lens redshift z{sub l} = 0.294, and image separation [theta] = 4.04 inch), SDSS J1254+2235 (z{sub s} = 3.626, [theta] = 1.56 inch), SDSS J1258+1657 (z{sub s} = 2.702, [theta] = 1.28 inch), SDSS J1339+1310 (z{sub s} = 2.243, [theta] = 1.69 cin), and SDSS J1400+3134 (z{sub s} = 3.317, [theta] = 1.74 inch). We estimate the lens redshifts of the latter four systems to be z{sub l} = 0.4-0.6 from the colors and magnitudes of the lensing galaxies. We find that the image configurations of all systems are well reproduced by standard mass models. Although these lenses will not be included in our statistical sample of z{sub s}

Author: Nial R. Tanvir
Publisher: World Scientific
ISBN: 9814530409
Category : Cosmology
Languages : en
Pages : 496

Get Book Here

Book Description
"Since the successful refurbishment mission, the Hubble Space Telescope has made dramatic and exciting progress in unravelling the nature of sources at high redshift. The upcoming installation of the next generation of instruments will give further impetus to the field, particularly in the infrared spectral region. The proceedings of this landmark meeting review the results of the first three years of post-repair data, including the deepest astronomical images ever obtained: the Hubble Deep Field. This was the first presentation of these exciting results at a major international conference. The interface between HST and ground-based facilities and planned programmes with forthcoming HST instruments are also extensively discussed."--Publisher's website.

Author: William C. Keel
Publisher: Springer Science & Business Media
ISBN: 9781852335748
Category : Science
Languages : en
Pages : 266

Get Book Here

Book Description
Written by one of the leading authorities in the field, this is one of the first book's to describe one of today's most important problems in cosmology - the formation of galaxies. The book tackles this great puzzle by discusses the beginnings of the process from cosmological observations and calculations, considers the broad features of galaxies that we need to explain and what we know of their later history. The author compares the competing theories for galaxy formation and considers the progress expected from new generations of powerful telescopes both on earth and in space. An intriguing text on one of today's greatest and most profound puzzles.

Author: Ralf Bender
Publisher: Springer Science & Business Media
ISBN: 9783540002055
Category : Science
Languages : en
Pages : 394

Get Book Here

Book Description
Measuring the masses of galaxies as a function of redshift is perhaps one of the most challenging open issues in current astronomical research. The evolution of the baryonic and dark matter components of galaxies is not only a critical test of the hierarchical formation paradigm, but ultimately also provides new clues on the complex interplay between star formation, the cooling and heating of gas and galaxy merging processes. This book reviews current techniques to measure the baryonic (stellar) and dark masses of nearby galaxies, and focusses on ongoing attempts to measure theses same quantities in galaxies at higher and higher redshifts. It also gives room to future perspectives, with special emphasis on new survey projects and satellite missions.

Author: David N. Schramm
Publisher: World Scientific
ISBN: 9789810220242
Category : Science
Languages : en
Pages : 750

Get Book Here

Book Description
This volume of important papers by one the world's leading astrophysicists provides a sweeping survey of the incisive and exciting applications of nuclear and particle physics to a wide range of problems in astrophysics and cosmology.The prime focus of the book is on Big Bang cosmology and the role of primordial nucleosynthesis in establishing the modern consensus on the Big Bang. This leads into the connection of cosmology to particle physics and the constraints put on various elementary particles by astrophysical arguments. Big Bang Nucleosynthesis has also led to the argument for nonbaryonic dark matter and is thus related to the major problem in physical cosmology today, namely, structure formation. The nuclear-particle interface with astrophysics also extends to the other topics of major interest such as the age of the universe, cosmic rays, supernovae, and solar neutrinos, each of which will be discussed in some detail. Each section contains historical papers, current papers, and frequently a popular article on the subject which provides an overview of the topic.This volume is testimony to the success of the integration of nuclear and particle physics with astrophysics and cosmology, and to the ingenuity of the work in this area which has earned the author numerous prestigious awards. The book, which is accessible to beginning graduate students, should be of particular interest to researchers and students in astronomy, astrophysics, cosmology and gravitation, and also in high energy and nuclear physics.