Download or read book Imaging at High Angular Resolution of Stellar Surfaces and Close Environment written by Nicolas Nardetto and published by EDP Sciences. This book was released on 2019-09-26 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: Imaging at high angular resolution (HRA) is a ?ourishing discipline. High performance instruments like the spectro-polarimeter SPHERE at VLT/ESO has recently been implemented. A harvest of splendid results is continuously coming from interferometry with PIONIER, MATISSE, and now GRAVITY (all at VLTI/ESO), VEGA and JouFlu (CHARA), and at longer wavelengths with ALMA at VLTI/ESO and NOEMA/IRAM. The future is already underway with the very close launch of JWST/NASA, and the development of ELT at ESO. HRA provides a unique way to study regions of stellar formation, proto-planetary discs as well as the surfaces of stars and their environments. This volume offers lectures given by world experts in the ?eld during the EvrySchatzman School on Stellar Physics (EES 2017) held in Roscoff, France. The addressed topics include a course of introduction to optical/IR interferometry covering the history and basic principles, a course on diffraction-dominated observational astronomy, and a course presenting the principles and instrumentation of optical long baseline interferometry. This book will be a valuable reference for researchers and students in the coming years.
Download or read book Imaging at High Angular Resolution of Stellar Surfaces and Close Environment written by Nicolas Nardetto and published by . This book was released on 2019 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Very High Angular Resolution Imaging written by J.G. Robertson and published by Springer Science & Business Media. This book was released on 2013-12-01 with total page 505 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 1990s are proving to be a very exciting p&iod for high angular resolution astronomy. At radio wavelengths a combination of new array instruments and pow erful imaging algorithms have generated images of unprecedented resolution and quality. In the optical and infrared, the great technical difficulties associated with constructing separated-aperture interferometers have been largely overcome, and many new instruments are now operating or are being developed. As these pro grams start to produce observational results they will be able to draw extensively on the experience gained by the radio-interferometry community. Thus it seemed that the time was ripe for a meeting which would bring together workers from all wavelength ranges to discuss the details of the science and art of "Very High Angular Resolution Imaging" . While the main emphasis of Symposium No. 158 was on high resolution tech niques from the radio, mm-wave, infrared and optical bands, it also provided an opportunity for presentation of astronomical results from these techniques. As well as giving our colleagues from the Northern Hemisphere a break from midwinter, the location of the Symposium in Australia recognised the continuing development of astronomical interferometry in this country, especially the recent completion of the Australia Telescope radio array, and the progress toward com missioning of the Sydney University Stellar Interferometer. A number of the par ticipants visited these instruments during the post-symposium tour.
Download or read book Astronomy at High Angular Resolution written by Henri M. J. Boffin and published by Springer. This book was released on 2016-08-24 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book offers an essential compendium of astronomical high-resolution techniques. Recent years have seen considerable developments in such techniques, which are critical to advances in many areas of astronomy. As reflected in the book, these techniques can be divided into direct methods, interferometry, and reconstruction methods, and can be applied to a huge variety of astrophysical systems, ranging from planets, single stars and binaries to active galactic nuclei, providing angular resolution in the micro- to tens of milliarcsecond scales. Written by experts in their fields, the chapters cover adaptive optics, aperture masking imaging, spectra disentangling, interferometry, lucky imaging, Roche tomography, imaging with interferometry, interferometry of AGN, AGN reverberation mapping, Doppler- and magnetic imaging of stellar surfaces, Doppler tomography, eclipse mapping, Stokes imaging, and stellar tomography. This book is intended to enable a next generation of astronomers to apply high-resolution techniques. It informs readers on how to achieve the best angular resolution in the visible and near-infrared regimes from diffraction-limited to micro-arcsecond scales.
Download or read book Electronic Imaging in Astronomy written by Ian S. McLean and published by Springer Science & Business Media. This book was released on 2008-06-25 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt: The second edition of Electronic Imaging in Astronomy: Detectors and Instrumentation describes the remarkable developments that have taken place in astronomical detectors and instrumentation in recent years – from the invention of the charge-coupled device (CCD) in 1970 to the current era of very large telescopes, such as the Keck 10-meter telescopes in Hawaii with their laser guide-star adaptive optics which rival the image quality of the Hubble Space Telescope. Authored by one of the world’s foremost experts on the design and development of electronic imaging systems for astronomy, this book has been written on several levels to appeal to a broad readership. Mathematical expositions are designed to encourage a wider audience, especially among the growing community of amateur astronomers with small telescopes with CCD cameras. The book can be used at the college level for an introductory course on modern astronomical detectors and instruments, and as a supplement for a practical or laboratory class.
Download or read book High Angular Resolution Imaging with VSOP written by Nihon Tenmon Gakkai and published by . This book was released on 2006 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High Resolution Imaging written by Swapan K. Saha and published by CRC Press. This book was released on 2015-01-28 with total page 590 pages. Available in PDF, EPUB and Kindle. Book excerpt: Interferometric observations need snapshots of very high time resolution of the order of (i) frame integration of about 100 Hz or (ii) photon-recording rates of several megahertz (MHz). Detectors play a key role in astronomical observations, and since the explanation of the photoelectric effect by Albert Einstein, the technology has evolved rather
Download or read book Scientific Drivers for ESO Future VLT VLTI Instrumentation written by J. Bergeron and published by Springer Science & Business Media. This book was released on 2002-08-06 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the start of a long process to ultimately operate new advanced capabilities at Paranal that can keep up with the evergrowing need for larger and more complex astrophysical data sets. A modern instrument represents a very significant investment in cash, human resources and time. Such a meeting gives us a precious yardstick to evaluate the competitiveness of 1st-generation instruments and associated current and forthcoming proposals for 1st-generation upgrades. This is also crucial to orient the large research and development effort that will provide the very foundation on which 2nd-generation VLT instrumentation can be built. Finally, it represents a significant step towards defining the hopes and goals for the future Extremely Large Telescope to come. The first outcome of this meeting, already in progress, is outlined in the epilogue.
Download or read book Diffraction Limited Imaging with Very Large Telescopes written by D.M. Alloin and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt: A few years ago, a real break-through happened in observational astronomy: the un derstanding of the effect of atmospheric turbulence on the structure of stellar images, and of ways to overcome this dramatic degradation. This opened a route to diffraction-limited observations with large telescopes in the optical domain. Soon, the first applications of this new technique led to some outstanding astrophysical results, both at visible and infrared wavelengths. Yet, the potential of interferometric observations is not fully foreseeable as the first long-baseline arrays of large optical telescopes are being built or cOIIllnissioned right now. In this respect a comparison with the evolution of radio-astronomy is tempting. From a situation where, in spite of the construction of giant antennas, low angular resolution was prevailing, the introduction of long baseline and very long baseline interferometry and the rapid mastering of sophisticated image reconstruction techniques, have brought on a nearly routine basis high dynamic range images with milliarcseconds resolution. This, of course, has completely changed our views of the radio sky.
Download or read book High Resolution Optical Imaging Through the Atmosphere written by Robert W. Noyes and published by . This book was released on 1989 with total page 57 pages. Available in PDF, EPUB and Kindle. Book excerpt: This program has concentrated on three major areas: the application of high angular resolution image reconstruction techniques to the reconstruction of solar surface features; speckle imaging of a wide range of astronomical sources; and the implementation of adaptive optics for faint object imaging. In this project, we have made substantial modifications to a technique for reconstruction of high resolution images from single short exposure solar frames, blind iterative deconvolution (IDC). We have been testing these improvements using numerical simulation data. Analysis of speckle data of the supernova SN1987A has detected a new bright source, 0.9 arcseconds south of the SN, as well as substantial structure in the region surrounding the SN. We also have new results on several Young Stellar Objects and supergiants. In the area of adaptive optics, an AOA wavefront sensor has been set up and tested using an image intensifier which increases its sensitivity by three orders of magnitude. Faint object image active tilt correction has also been tested with some important enhancements, including new highly linear and sensitive CCD quad cells developed by Cal Tech and Tektronix, and an off-the-shelf high speed 2-D tilting mirror with greatly improved specifications. The effects of only partially correcting atmospheric turbulence have been theoretically analyzed and numerically simulated.
Download or read book Lessons from the Local Group written by Kenneth Freeman and published by Springer. This book was released on 2016-09-10 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Our understanding of galaxy formation comes mostly from two sources: sensitive observations at high angular resolution of the high-redshift Universe, where galaxies are observed to be forming, and detailed observations of individual stars and clouds in the Local Group, where telltale remnants from its formative time remain and similar processes operate at a low level today. The current conference focusses on key aspects of the Local Group, composed of the Milky Way, Andromeda and Triangulum Spiral Galaxies, the Large and Small Magellanic Cloud galaxies, numerous dwarf and irregular galaxies, and intergalactic gas. Topics include the halo and thick disk of the Milky Way with its first stars and stellar streams; the Milky Way bar, bulge and outer edge; interstellar dust and turbulence; star formation processes and stellar scattering in spiral arms; views through the infrared Eyes of the Spitzer Space Telescope; globular clusters; the Local Gould Belt; stellar metallicities and elemental abundances; the environment and black hole in the Milky Way nucleus; orbits of the Magellanic Clouds and galaxy dwarfs; interstellar dust and turbulence; the outer disks and halos of the Andromeda and Triangulum galaxies; ripples from a collision in Andromeda; and arcs of carbon stars in the Triangulum and intergalactic clouds. This volume also discusses surveys of planetary nebulae, galaxy morphology at low and high redshift, cosmic evolution of star and galaxy formation and gas accretion, Lyman alpha emitting galaxies, ultra-low surface brightness imaging, and more. Readers are given a clear and comprehensive view of this wide range of topics written by specialists in each field. This is the proceedings of an International Conference at the Seychelles archipelago in May 2014, on the occasion of the 60th birthday of David Block and the millionth (base two) birthday of Bruce Elmegreen.
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 High Angular Resolution Spectroscopic and Polarimetric Imaging of the Galactic Center in the Near infrared written by Andreas Eckart and published by . This book was released on 1995 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Planetary Sciences written by National Academy of Sciences and published by National Academies Press. This book was released on 1991-02-01 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains the proceedings from a workshop on planetary sciences sponsored by the Academy of Sciences of the USSR and the National Academy of Sciences. The proceedings include papers written by American and Soviet scientists who examine the current theoretical understanding of how the planets were formed and how they evolved to their present state. They assess the type of observations and experiments that are needed to advance understanding of the formation and evolution of the solar system based on the current theoretical framework.
Download or read book Extending the Limits of Direct High Angular Resolution Infrared Astronomical Imaging written by Richard Brockie and published by . This book was released on 1998 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Active Close Binaries written by Cafer Ibanogammalu and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 898 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the 1970s symposia or colloquia devoted to recent research on close binaries have been held around the world almost annually. At meetings of the General Assembly of the International Astronomical Union this topic has also been discussed in detail at presentations in various commission meetings and also as invited talks by leading astronomers in the field. In recent years, fundamental changes have taken place in the study of close binaries due to the improvements in observational techniques, extension of observations from X-ray to radio regions of the electromagnetic spectrum, and advances in theoretical studies. For more than a decade, a group of astronomers at Ege University Observatory has been concentrating on active close binaries with particular emphasis on the behaviour of the light curves of chromospherically active systems. Thus, we decided to organize an international meeting in Western Anatolia, where this part of Turkey had been the cradle for great developments in science during antiquity. KUljadasi, located only minutes away from Ephesus, one of the seven wonders of the world, was selected to be the meeting site. Close binary systems constitute a very rich source of information about the physical properties of the component stars. Some systems are eclipsing variables, where periodic recurrences of eclipses are observed as comparatively brief decreases in the total brightness of the binary system. Precise methods of photometric observations make it possible to obtain the light variations of these systems because of eclipses and other phenomena.
Download or read book Close Binaries in the 21st Century New Opportunities and Challenges written by Alvaro Gimenez and published by Springer Science & Business Media. This book was released on 2007-04-05 with total page 349 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is the proceedings of an international conference entitled "Close Binaries in the 21st Century: New Opportunities and Challenges", held in Syros island, Greece, June 27-30, 2005. The papers collected in this volume detail the latest achievements in the field and reflect the state of the art of the dynamically evolving area of binary star research.
