Diffraction-Limited Imaging with Very Large Telescopes PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Diffraction-Limited Imaging with Very Large Telescopes PDF full book. Access full book title Diffraction-Limited Imaging with Very Large Telescopes by D.M. Alloin. Download full books in PDF and EPUB format.
Author: D.M. Alloin
Publisher: Springer Science & Business Media
ISBN: 9400923406
Category : Science
Languages : en
Pages : 444
Get Book Here
Book Description
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.
Author: D.M. Alloin
Publisher: Springer Science & Business Media
ISBN: 9400923406
Category : Science
Languages : en
Pages : 444
Get Book Here
Book Description
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.
Author: Swapan K Saha
Publisher: World Scientific
ISBN: 9814475130
Category : Science
Languages : en
Pages : 633
Get Book Here
Book Description
This book deals with the fundamentals of wave optics, polarization, interference, diffraction, imaging, and the origin, properties, and optical effects of turbulence in the Earth's atmosphere. Techniques developed during the last few decades to overcome atmospheric image degradation (including passive methods, speckle interferometry in particular, and active methods such as adaptive optics), are highlighted. Also discussed are high resolution sensors, image processing, and the astronomical results obtained with these techniques.
Author:
Publisher:
ISBN:
Category : Astronautics
Languages : en
Pages : 490
Get Book Here
Book Description
Author: D.M. Rabin
Publisher: Springer Science & Business Media
ISBN: 9401119260
Category : Science
Languages : en
Pages : 587
Get Book Here
Book Description
Infrared Solar Physics contains the proceedings of the 154th Symposium of the International Astronomical Union held in Tucson, Arizona, March 2--5, 1992. Aimed at active workers and graduate students in solar physics, this volume provides the first comprehensive view of a rapidly expanding discipline that gives us a new perspective on the sun. Measurements across the wide infrared spectral range -- here, from 1 mum to 1 mm -- can probe the solar atmosphere from below the visible surface through the outer reaches of the corona. Taking full advantage of revolutionary advances in detector technology, infrared observations from the ground, aircraft and space have led to a better understanding of solar magnetic fields, atmospheric structure and activity, and elemental abundances. The infrared has also provided new interpretive challenges, such as the appearance of the 12-mum emission lines of magnesium. These and other developments are discussed here by the leading contributors to the field, who also give their perspectives on the future of this rich field of study.
Author: Jan Olof Stenflo
Publisher: Springer Science & Business Media
ISBN: 9400910614
Category : Science
Languages : en
Pages : 546
Get Book Here
Book Description
Solar and stellar photospheres constitute the layers most accessible to observations, forming the interface between the interior and the outside of the stars. The solar atmosphere is a rich physics laboratory, in which the whole spectrum of radiative, dynamical, and magnetic processes that tranfer energy into space can be observed. As the fundamental processes take place on very small spatial scales, we need high· resolution observations to explore them. On the other hand the small-scale processes act together to form global properties of the sun, which have their origins in the solar interior. The rapid advances in observational techniques and theoreticallllodelling over the past decade made it very timely to bring together scientists from east and west to the first lAU Symposium on this topic. The physics of the photosphere involves complicated interactions between magnetic fields, convection, waves, and radiation. During the past decade our understanding of these gener ally small-scale structures and processes has been dramatically advanced. New instrumen tations, on ground and in space, have given us new means to study the granular convection. Diagnostic methods in Stokes polarimetry have allowed us to go beyond the limitations of spatial resolution to explore the structure and dynamics of the subarcsec magnetic struc tures. Extensive numerical simulations of the interaction between convection and magnetic fields using powerful supercomputers are providing deepened physical insight. Granulation, magnetic fields, and dynamo processes are being explored in the photospheres of other stars, guided by our improved understanding of the solar photosphere.
Author: Jack O. Burns
Publisher:
ISBN:
Category : Astronomical instruments
Languages : en
Pages : 300
Get Book Here
Book Description
Part 1 is an introduction. Part 2 is a description of current and planned ground-based interferometers. Part 3 is a description of potential space-based interferometers. Part 4 addresses the potential for interferometry on the moon. Part 5 is the report of the workshop's working groups. Concluding remarks, summary, and conclusions are presented in Part 6.
Author: Francesco Paresce
Publisher: Springer Science & Business Media
ISBN: 354069398X
Category : Science
Languages : en
Pages : 414
Get Book Here
Book Description
It has always been ESO's aim to operate the VLT in an interferometric mode (VLTI) which allows the coherent combination of stellar light beams col lected by the four 8-m telescopes and by several smaller auxiliary telescopes. In December 1993, in response to financial difficulties, the ESO Council de cided to postpone implement at ion of the VLTI, Coude trains and associated adaptive optics for all the UTs but included provisions for continuing tech nological and development programmes devoted to the aim of reintroducing these capabilities at the earliest possible date. The desirability of carrying out the full VLTI programme as originally envisaged at the earliest possible moment has not, however, diminished, es pecially in view of VLTI's exceptional capabilities and resulting potential for new and exciting discoveries. In recent years, interferometric projects have begun to playa central role in ground-based high-resolution astronomy, and numerous instruments have been completed or are in the process of construc tion. Several large-aperture interferometers will probably co me on-line near the turn of the century. The impending presence of these new instruments represents an important incentive both for clarifying the scientific cases for various VLTI implementation plans and for ensuring VLTI's competitiveness in the international context over the next 1O~20 years.
Author: Thomas Wilson
Publisher: Springer Science & Business Media
ISBN: 3540851216
Category : Science
Languages : en
Pages : 520
Get Book Here
Book Description
Four signi?cant factors have led us to update this text. The ?rst is the breathtaking progress in technology, especially in receiver and digital techniques. The second is the advance of radio astronomy to shorter wavelengths, and the increased availab- ity of astronomical satellites. The third is a need to reorganize some of the chapters in order to separate the basic theory, that seldom changes, from practical aspects that change often. Finally, it is our desire to enhance the text by including problem sets for each chapter. In view of this ambitious plan, we have expanded the number of authors. In the reorganization of this edition, we have divided Chap. 4 of the 4th edition into two Chaps. 4 and 5. The ?rst remains Chap. 4, with a slightly different - tle, Signal Processing and Receivers: Theory. This was expanded to include digital processing and components including samplers and digitizers. In Chap. 5, Prac- cal Receiver Systems. we have relegated the presentations of maser and parametric ampli?er front ends, which are no longer commonly used as microwave receivers in radio astronomy, to a short section on “historical developments” and We have retained and improved the presentations of current state-of-the-art devices, cooled transistor and superconducting front ends. We have also included descriptions of local oscillators and phase lock loops. Chapters 5 and 6 in the 4th edition has now become Chap. 6, Fundamentals of Antenna Theory and Chap.
Author: Paulo J.V. Garcia
Publisher: Springer Science & Business Media
ISBN: 9401701571
Category : Science
Languages : en
Pages : 313
Get Book Here
Book Description
A JENAM 2002 Workshop, Porto, Portugal, 3-5 September 2002
Author: David F. Buscher
Publisher: Cambridge University Press
ISBN: 1107042178
Category : Science
Languages : en
Pages : 287
Get Book Here
Book Description
A practically focused guide to optical interferometry, bringing together core concepts needed to plan observations, analyse data and reconstruct images.
