Download or read book Observations of the Jet of the Quasar 3C 273 written by Amy J. Lovell and published by . This book was released on 1990 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book New Chandra Observations of the Jet in 3C273 1 Softer X ray Than Radio Spectra and the X ray Emission Mechanism written by and published by . This book was released on 2006 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: The jet in 3C273 is a high-power quasar jet with radio, optical and X-ray emission whose size and brightness allow a detailed study of the emission processes acting in it. We present deep Chandra observations of this jet and analyze the spectral properties of the jet emission from radio through X-rays. We find that the X-ray spectra are significantly softer than the radio spectra in all regions of the bright part of the jet except for the first bright ''knot A'', ruling out a model in which the X-ray emission from the entire jet arises from beamed inverse-Compton scattering of cosmic microwave background photons in a single-zone jet flow. Within two-zone jet models, we find that a synchrotron origin for the jet's X-rays requires fewer additional assumptions than an inverse-Compton model, especially if velocity shear leads to efficient particle acceleration in jet flows.

Download or read book Deep Sky Wonders written by Sue French and published by Firefly Books. This book was released on 2020-10 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The quality of the deep-sky images is outstanding--a tribute to the various photographers as well as the book's printer. But it's the written word that will make or break a book like this, and Sue's writing is superb... [For] an occasional stargazer, a serious observer, or anyone in between, you won't go wrong with Deep-Sky Wonders. This is a great introduction to deep-sky stargazing for novice and experienced amateur astronomers alike." --Mercury, publication of the Astronomical Society of the Pacific Sue French writes the popular column "Deep-Sky Wonders" for Sky and Telescope magazine and also teaches deep sky observation. She has earned a loyal following among enthusiasts and is welcomed by beginners for her skill at presenting astronomy in an understandable way. After selling 10,000 copies of Deep-Sky Wonders in hardcover, we expect a good response for this paperback edition at an accessible price. Deep-Sky Wonders is a collection of 100 of French's best "Deep-Sky Wonders" columns originally published in Sky and Telescope, which has a monthly readership exceeding 100,000. The book is organized by season and subdivided into months for a total of 100 in-depth tours of the deep sky. Each deep sky tour illuminates little-known seasonal wonders that lie off the beaten path. Features include: Full-color photographs and detailed sketches of each deep sky tour Descriptions of double and variable stars, star clusters, nebulae, galaxies and exotics Historical and scientific background of particular interest A tabular listing of the deep-sky sites Color charts showing the position of each target in the night sky An index to all of the deep-sky objects covered. Deep-Sky Wonders also features a variety of challenging objects that encourage observers to test the limits of their equipment and skills. Suitable for beginner and intermediate small-scope astronomers as well as large-scope viewers and astrophotographers, this book will be greeted enthusiastically by all Sky and Telescope readers. It is also an outstanding introduction to deep-sky viewing for novice observers.

Download or read book Relativistic Jets from Active Galactic Nuclei written by Markus Boettcher and published by John Wiley and Sons. This book was released on 2012-02-13 with total page 425 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by a carefully selected consortium of researchers working in the field, this book fills the gap for an up-to-date summary of the observational and theoretical status. As such, this monograph includes all used wavelengths, from radio to gamma, the FERMI telescope, a history and theory refresher, and jets from gamma ray bursts. For astronomers, nuclear physicists, and plasmaphysicists.

Download or read book Death from the Skies written by Philip C. Plait and published by Penguin. This book was released on 2008 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt: It's only a matter of time before a cosmic disaster spells the end of the Earth. But how concerned should we about about any of these catastrophic scenarios? And if they do post a danger, can anything be done to stop them?

Download or read book Relativistic Astrophysics and Cosmology Einstein s Legacy written by Bernd Aschenbach and published by Springer Science & Business Media. This book was released on 2007-10-20 with total page 527 pages. Available in PDF, EPUB and Kindle. Book excerpt: The year 2005, which marked the 100th anniversary of the 'annus mirabilis', the year in which Albert Einstein published three of his most important scientific papers, was the perfect opportunity to review and to present the current scientific understanding of relativistic topics. This book provides an up-to-date reference on the theory of gravity, relativistic astrophysics and cosmology. It is a useful reference tool for both the expert and the new-comer in these fields.

Download or read book High resolution Multi wavelength Study of the Jet in 3C273 written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The jet in 3C273 is one of only a few extragalactic optical synchrotron jets which are large and bright enough to be studied in detail. We present new broad-band observations of this jet at the unprecedented common resolution of 0.3' which have been obtained with the Very Large Array at radio and the Hubble Space Telescope at infrared, optical and ultraviolet wavelengths. These observations reveal a flattening of the high-frequency spectrum of the jet, a surprising feature which cannot be accounted for by any single-population synchrotron model. Both the observed flattening of the high-frequency spectrum and the X-ray emission from the jet can be explained by a model in which two distinct electron populations contribute to the jet's emission. We fit spatially resolved synchrotron spectra for the jet and determine the run of the maximum particle energy. The decrease of the maximum particle energy along the jet is much slower than expected from the observed synchrotron emission. We find no evidence for localised acceleration or loss sites. We show that relativistic beaming and/or sub-equipartition magnetic fields cannot remove the discrepancy between light-travel time along the jet and the shorter lifetime of electrons emitting optical synchrotron radiation. We consider this further evidence in favour of a distributed electron acceleration process.

Download or read book Astronomy and Astrophysics Abstracts written by S. Böhme and published by Springer Science & Business Media. This book was released on 2013-12-14 with total page 930 pages. Available in PDF, EPUB and Kindle. Book excerpt: Astronomy and Astrophysics Abstracts aims to present a comprehensive documen tation of the literature concerning all aspects of astronomy, astrophysics, and their border fields. It is devoted to the recording, summarizing, and indexing of the relevant publications throughout the world. Astronomy and Astrophysics Abstracts is prepared by a special department of the Astronomisches Rechen-Institut under the auspices of the International Astronomical Union. Volume 34 records literature published in 1983 and received before February 17, 1984. Some older documents which we received late and which are not surveyed in earlier volumes are included too. We acknowledge with thanks contributions of our colleagues all over the world. We also express our gratitude to all organiza tions, observatories, and publishers which provide us with complimentary copies of their publications. Starting with Volume 33, all the recording, correction, and data processing work was done by means of computers. The recording was done by our technical staff members Ms. Helga Ballmann, Ms. Mona El-Choura and Ms. Monika Kohl. Mr. Martin Schlotelburg and Mr. Ulrich Oberall supported our task by careful proofreading. It is a pleasure to thank them all for their encouragement. Heidelberg, March 1984 The Editors Contents Introduction . . . . . . . . . . . . Concordance Relation: ICSU-AB-AAA 3 Abbreviations 10 Periodicals, Proceedings, Books, Activities 001 Periodicals . . . . . . . . . . . 15 002 Bibliographical Publications, Documentation, Catalogues, Atlases 50 003 Books ...... . 58 004 History of Astronomy 67 005 Biography . . 71 006 Personal Notes 73 007 Obituaries . . .

Download or read book Ninth Texas Symposium on Relativistic Astrophysics written by Jürgen Ehlers and published by . This book was released on 1980 with total page 624 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Parsec Scale Radio Jets written by J. Anton Zensus and published by Cambridge University Press. This book was released on 1990-08-16 with total page 430 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quasars and active galaxies are the most powerful emitters of radiation in the universe. Modern radio telescope arrays have shown that the ultimate energy source resides in the central few parsecs of the galactic nucleus, and powers the emitting regions by way of two oppositely-directed relativistic jets of energy. This volume presents the latest observations and theories of these remarkable objects. Topics discussed include superluminal motions, the physics of jets and shock fronts in jets, related optical observations, and cosmic evolution. Particular attention is given to the "unified theories," which attempt to show that many of the phenomena in powerful extragalactic objects are different aspects of a single, basic mechanism; the main difference in their appearance is a result of their different orientation with respect to the observer.

Download or read book Dynamics and Evolution of the Jet from Quasar 3C273 written by Dana Leigh Roberts and published by . This book was released on 1983 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Astronomy Reports written by and published by . This book was released on 1993 with total page 762 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Literature 1984 Part 1 written by S. Böhme and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 947 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Astroparticle Particle Space Physics and Detectors for Physics Applications written by S. Giani and published by World Scientific. This book was released on 2012 with total page 1100 pages. Available in PDF, EPUB and Kindle. Book excerpt: The exploration of the subnuclear world is done through increasingly complex experiments covering a wide range of energy and performed in a large variety of environments ranging from particle accelerators, underground detectors to satellites and the space laboratory. Among recent advances one has to indicate, for instance, first results obtained from space and LHC experiments and progress done in preparation of the latter experiments upgrades, including plans for the LHC machine upgrade. The achievement of these research programs calls for novel techniques, new materials and instrumentation to be used in detectors, often of large scale. Therefore, fundamental physics is at the forefront of technological advance and also leads to many applications. Among these, medical applications have a particular importance due to health and social benefits they bring to the public. Sample Chapter(s). Science highlights from the Fenni Observatory (5,046 KB). Contents: Space Experiments and Cosmic Rays Observations; Production and Propagation of Cosmic Rays in the Galaxy and Heliosphere; Dark Matter Searches, Underwater and Underground Experiments; High Energy Physics Experiments; Tracker and Position Sensitive Detectors; Calorimetry; Advanced Detectors, Particles Identication, Devices and Materials in Radiation; Broader Impact Activities, Treatments and Software Application. Readership: Post-graduate students, researchers and engineers.

Download or read book Astrophysical Jets and Beams written by Michael D. Smith and published by Cambridge University Press. This book was released on 2012-02-16 with total page 241 pages. Available in PDF, EPUB and Kindle. Book excerpt: An up-to-date study of astrophysical jets that will appeal to students and researchers in all areas of astrophysics.

Download or read book Stellar Astrophysics written by K.S. Cheng and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 349 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Pacific Rim Conferences for the first decade from the mid 1980's to the mid 1990's were primary concerned with binary stars research. The Conference expanded to all areas of Stellar Astrophysics for the last two meetings in Hong Kong; at Hong Kong University of Science and Technology in 1997 and at the Hong Kong University in 1999. At the conclusion of the very successful Pacific Rim Conference on Stellar Astrophysics held in Hong Kong University, members of the Sci entific Organizing Committee began planning for the next conference. We approached Professor Tan Lu of Nanjing University and Professor Tipei Li of the Institute of High Energy Physics about hosting a con ference in China. The city of Xi'an in Shaanxi province and a city in Yunnan province, were considered to be the most likely locations. It be came crucial to find the right person to serve as Chair (or Co-chairs) for the Local Organizing Committee. Initially, Professor Lu was the logical choice but he declined for personal reasons. Professor Li was invited to lead a new department of Astrophysics at Tsinghua University so he could not take on the additional load of chairing the LOC. Professor Gang Zhao of Beijing Astronomical Observatory was approached to take on the task but he also declined. This has been a busy time for Chinese astronomers. The SOC decided to have the conference dedicated to honor Dr. Helmut A.

Download or read book Stellar Astrophysics written by Ka Lok Cheng and published by Springer Science & Business Media. This book was released on 2003-11-30 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Pacific Rim Conferences for the first decade from the mid 1980's to the mid 1990's were primary concerned with binary stars research. The Conference expanded to all areas of Stellar Astrophysics for the last two meetings in Hong Kong; at Hong Kong University of Science and Technology in 1997 and at the Hong Kong University in 1999. At the conclusion of the very successful Pacific Rim Conference on Stellar Astrophysics held in Hong Kong University, members of the Sci entific Organizing Committee began planning for the next conference. We approached Professor Tan Lu of Nanjing University and Professor Tipei Li of the Institute of High Energy Physics about hosting a con ference in China. The city of Xi'an in Shaanxi province and a city in Yunnan province, were considered to be the most likely locations. It be came crucial to find the right person to serve as Chair (or Co-chairs) for the Local Organizing Committee. Initially, Professor Lu was the logical choice but he declined for personal reasons. Professor Li was invited to lead a new department of Astrophysics at Tsinghua University so he could not take on the additional load of chairing the LOC. Professor Gang Zhao of Beijing Astronomical Observatory was approached to take on the task but he also declined. This has been a busy time for Chinese astronomers. The SOC decided to have the conference dedicated to honor Dr. Helmut A.