Download or read book Astronomical Polarimetry written by Jaap Tinbergen and published by Cambridge University Press. This book was released on 2005-08-22 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: Radiation from astronomical objects generally shows some degree of polarization. Although this polarized radiation is usually only a small fraction of the total radiation, it often carries a wealth of information on the physical state and geometry of the emitting object and intervening material. Measurement of this polarized radiation is central to much modern astrophysical research. This handy volume provides a clear, comprehensive and concise introduction to astronomical polarimetry at all wavelengths. Starting from first principles and a simple physical picture of polarized radiation, the reader is introduced to all the key topics, including Stokes parameters, applications of polarimetry in astronomy, polarization algebra, polarization errors and calibration methods, and a selection of instruments (from radio to X-ray). The book is rounded off with a number of useful case studies, a collection of exercises, an extensive list of further reading and an informative index. This review of all aspects of astronomical polarization provides both an essential introduction for graduate students, and a valuable reference for practising astronomers.

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 Working Papers written by National Research Council and published by National Academies Press. This book was released on 1991-02-01 with total page 347 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains working papers on astronomy and astrophysics prepared by 15 non-National Research Council panels in areas ranging from radio astronomy to the status of the profession.

Download or read book Adaptive Optics for Astronomical Telescopes written by John W. Hardy and published by Oxford Optical and Imaging Sci. This book was released on 1998 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book by one of the leaders in adaptive optics covers the fundamental theory and then describes in detail how this technology can be applied to large ground-based telescopes to compensate for the effects of atmospheric turbulence. It includes information on basic adaptive optics components and technology, and has chapters devoted to atmospheric turbulence, optical image structure, laser beacons, and overall system design. The chapter on system design is particularly detailed and includes performance estimation and optimization. Combining a clear discussion of physical principles with numerous real-world examples, this book will be a valuable resource for all graduate students and researchers in astronomy and optics.

Download or read book Scientific Requirements for Extremely Large Telescopes IAU S232 written by International Astronomical Union. Symposium and published by Cambridge University Press. This book was released on 2006-06-15 with total page 552 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings volume for researchers and graduate students of astronomy, covering the most exciting science and key ELT projects.

Download or read book Orthogonal Polynomials of Several Variables written by Charles F. Dunkl and published by Cambridge University Press. This book was released on 2014-08-21 with total page 439 pages. Available in PDF, EPUB and Kindle. Book excerpt: Updated throughout, this revised edition contains 25% new material covering progress made in the field over the past decade.

Download or read book Index to Theses with Abstracts Accepted for Higher Degrees by the Universities of Great Britain and Ireland and the Council for National Academic Awards written by and published by . This book was released on 2006 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt: Theses on any subject submitted by the academic libraries in the UK and Ireland.

Download or read book Brown Dwarf Companions to Young Solar an written by Stanimir Metchev and published by Universal-Publishers. This book was released on 2006-02 with total page 255 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present results from an adaptive optics survey conducted with the Palomar and Keck telescopes over 3 years, which measured the frequency of stellar and sub-stellar companions to Sun-like stars. The survey sample contains 266 stars in the 3-10000 million year age range at heliocentric distances between 8 and 200 parsecs and with spectral types between F5-K5. A sub-sample of 101 stars, between 3-500 million years old, were observed in deep exposures with a coronagraph to search for faint sub-stellar companions. A total of 288 candidate companions were discovered around the sample stars, which were re-imaged at subsequent epochs to determine physical association with the candidate host stars by checking for common proper motion. Benefitting from a highly accurate astrometric calibration of the observations, we were able to successfully apply the common proper motion test in the majority of the cases, including stars with proper motions as small as 20 milli-arcseconds/year. The results from the survey include the discovery of three new brown dwarf companions (HD 49197B, HD 203030B, and ScoPMS 214B), 43 new stellar binaries, and a triple system. The physical association of an additional, a priori-suspected, candidate sub-stellar companion to the star HII 1348 is astrometrically confirmed. The newly-discovered and confirmed young brown dwarf companions span a range of spectral types between M5 and T0.5, and will be of prime significance for constraining evolutionary models of young brown dwarfs and extra-solar planets. Based on the 3 new detections of sub-stellar companions in the 101 star sub-sample and following a careful estimate of the survey incompleteness, a Bayesian statistical analysis shows that the frequency of 0.012-0.072 solar-mass brown dwarfs in 30-1600 AU orbits around young solar analogs is 6.8% (-4.9%, +8.3%; 2-sigma limits). While this is a factor of 3 lower than the frequency of stellar companions to G-dwarfs in the same orbital range, it is significantly higher than the frequency of brown dwarfs in 0-3 AU orbits discovered through precision radial velocity surveys. It is also fully consistent with the observed frequency of 0-3 AU extra-solar planets. Thus, the result demonstrates that the radial-velocity "brown dwarf desert" does not extend to wide separations, contrary to previous belief.

Download or read book Star Formation at High Angular Resolution written by International Astronomical Union. Symposium and published by Astronomical Society of the Pacific. This book was released on 2004 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book National Science Foundation NSF Forum on Optical Science and Engineering written by William H. Carter and published by . This book was released on 1995 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Instrumentation in Astronomy VII written by David Livingstone Crawford and published by SPIE-International Society for Optical Engineering. This book was released on 1990 with total page 550 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1972 with total page 1070 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optics in Astrophysics written by Renaud Foy and published by Springer Science & Business Media. This book was released on 2006-01-14 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt: Astrophysics is facing challenging aims such as deep cosmology at redshift higher than 10 to constrain cosmology models, or the detection of exoplanets, and possibly terrestrial exoplanets, and several others. It requires unprecedented ambitious R&D programs, which have definitely to rely on a tight cooperation between astrophysics and optics communities. The book addresses most of the most critical interdisciplinary domains where they interact, or where they will do. A first need is to collect more light, i.e. telescopes still larger than the current 8-10 meter class ones. Decametric, and even hectometric, optical (from UV to IR wavelengths) telescopes are being studied. Whereas up to now the light collecting surface of new telescopes was approximately 4 times that of the previous generation, now this factor is growing to 10 to 100. This quantum leap urges to implement new methods or technologies developed in the optics community, both in academic labs and in the industry. Given the astrophysical goals and technological constraints, new generation adaptive optics with a huge number of actuators and laser guide stars devices have to be developed, from theoretical bases to experimental works. Two other newcomers in observational astrophysics are interferometric arrays of optical telescopes and gravitational wave detectors. Up-to-date reviews of detectors and of spectrographs are given, as well as forefront R&D in the field of optical coatings and of guided optics. Possible new ways to handle photons are also addressed, based on quantum physics. More and more signal processing algorithms are a part and parcel of any modern instrumentation. Thus finally the book gives two reviews about wavefront processing and about image restoration and deconvolution algorithms for ill conditioned cases.

Download or read book Principles of Stellar Interferometry written by Andreas Glindemann and published by Springer Science & Business Media. This book was released on 2011-01-04 with total page 359 pages. Available in PDF, EPUB and Kindle. Book excerpt: The imaging process in stellar interferometers is explained starting from first principles on wave propagation and diffraction. Wave propagation through turbulence is described in detail using Kolmogorov statistics. The impact of turbulence on the imaging process is discussed both for single telescopes and for interferometers. Correction methods (adaptive optics and fringe tracking) are presented including wavefront sensing/fringe sensing methods and closed loop operation. Instrumental techniques like beam combination and visibility measurements (modulus and phase) as well as Nulling and heterodyne interferometry are described. The book closes with examples of observing programmes linking the theory with individual astrophysical programmes.

Download or read book Ground based Solar Research written by National Research Council (U.S.). Task Group on Ground-based Solar Research and published by National Academies. This book was released on 1998 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book New Worlds New Horizons in Astronomy and Astrophysics written by National Research Council and published by National Academies Press. This book was released on 2011-02-04 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: Driven by discoveries, and enabled by leaps in technology and imagination, our understanding of the universe has changed dramatically during the course of the last few decades. The fields of astronomy and astrophysics are making new connections to physics, chemistry, biology, and computer science. Based on a broad and comprehensive survey of scientific opportunities, infrastructure, and organization in a national and international context, New Worlds, New Horizons in Astronomy and Astrophysics outlines a plan for ground- and space- based astronomy and astrophysics for the decade of the 2010's. Realizing these scientific opportunities is contingent upon maintaining and strengthening the foundations of the research enterprise including technological development, theory, computation and data handling, laboratory experiments, and human resources. New Worlds, New Horizons in Astronomy and Astrophysics proposes enhancing innovative but moderate-cost programs in space and on the ground that will enable the community to respond rapidly and flexibly to new scientific discoveries. The book recommends beginning construction on survey telescopes in space and on the ground to investigate the nature of dark energy, as well as the next generation of large ground-based giant optical telescopes and a new class of space-based gravitational observatory to observe the merging of distant black holes and precisely test theories of gravity. New Worlds, New Horizons in Astronomy and Astrophysics recommends a balanced and executable program that will support research surrounding the most profound questions about the cosmos. The discoveries ahead will facilitate the search for habitable planets, shed light on dark energy and dark matter, and aid our understanding of the history of the universe and how the earliest stars and galaxies formed. The book is a useful resource for agencies supporting the field of astronomy and astrophysics, the Congressional committees with jurisdiction over those agencies, the scientific community, and the public.

Download or read book Literature 1980 Part 1 written by Siegfried Böhme and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 949 pages. Available in PDF, EPUB and Kindle. Book excerpt: Astronomy and Astrophysics Abstracts, which has appeared in semi-annual volumes since 1969, is de voted to the recording, summarizing and indexing of astronomical publications throughout the world. It is prepared under the auspices of the International Astronomical Union (according to a resolution adopted at the 14th General Assembly in 1970). Astronomy and Astrophysics Abstracts aims to present a comprehensive documentation of literature in all fields of astronomy and astrophysics. Every effort will be made to ensure that the average time interval between the date of receipt of the original literature and publication of the abstracts will not exceed eight months: This time interval is near to that achieved by monthly abstracting journals, com pared to which our system of accumulating abstracts for about six months offers the advantage of greater convenience for the user. I, 1980; some older Volume 27 contains literature published in 1980 and received before August literature which was received late and which is not recorded in earlier volumes is also included. We acknowledge with thanks contributions to this volume by Dr. J. Bouska, Prague, who surveyed journals and publications in Czech and supplied us with abstracts in English.