Author : Heikki Ilmari Helava
Publisher :
Page : 170 pages
File Size : 47,90 MB
Release : 1975
Category : Cygnus Loop (Constellation)
ISBN :
Author :
Publisher :
Page : 680 pages
File Size : 18,21 MB
Release : 1976
Category : Nuclear energy
ISBN :
Author : S. Böhme
Publisher : Springer Science & Business Media
Page : 655 pages
File Size : 30,27 MB
Release : 2013-11-11
Category : Science
ISBN : 3662123045
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 averagetime interval between the date of receipt of the original literature and publication ofthe 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. Volume 17 contains literature published in 1976 and received before August 15, 1976; some older 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, who surveyed journals and publications in the Czech languageand supplied us with abstracts in English,and by the Common wealth Scientific and Industrial Research Organization (C.S.I.R.O.), Sydney, for providing titles and abstracts of papers on radio astronomy. We want to acknowledge valuable contributions to this vol ume by Zentralstelle fur Atomkernenergie-Dokumentation, Leopoldshafen, which supported our ab stracting service by sending us retrospective literature searches.
Author : C.B. Cosmovici
Publisher : Springer Science & Business Media
Page : 378 pages
File Size : 26,39 MB
Release : 2012-12-06
Category : Science
ISBN : 940102166X
This conference is a tribute to those astronomers who pioneered the investigation of this subject such a short time ago and who carried it through to its present state. (H. Arp, Concluding Remarks of the Conference) A previous conference, covering mainly the observational aspects of Supernovae, was held at the Haute Provence Observatory in September 1963. In the following ten years this field of research has considerably increased; it seemed, therefore, the right time to organize an international conference on Supernovae taking into account that in the meantime important discoveries, such as the Pulsars, had been made, and new techniques of observation were available. This book contains the proceedings of this conference held at Porto Cesareo (Lecce), Italy, during the period May 7 through 11, 1973. About one hundred participants from eighteen countries attended the conference. It was also the first attempt to hold an international conference in the Salento, the southernmost region of Apulia, in whose capital, Lecce, the newly founded Faculty of Sciences of the University of Lecce is located. The program of the conference included the results and techniques of Supernova surveys, photometric and spectral studies, statistics of Supernovae, Supernova Rem nants, and finally, theories on Supernovae and Supernova Remnants.
Author : H. Bradt
Publisher : Springer Science & Business Media
Page : 323 pages
File Size : 48,74 MB
Release : 2012-12-06
Category : Science
ISBN : 9401025851
The IAU Symposium No. 55 on 'X-Ray and Gamma-Ray Astronomy' has occurred, not entirely by coincidence, at an important moment in the development of these new branches of observational astronomy. In X-ray astronomy the data from the first X-ray observatory UHURU have contributed to a new view of the X-ray sky and a new conception of the nature and properties of galactic and extragalactic X-ray sources. In gamma-ray astronomy the exciting and often controversial nature of the results underlines the importance of the forthcoming launch of SAS-B, the first orbiting y-ray observatory. As Bruno Rossi reminds us (p. I), the Symposium occurred almost exactly ten years after the first detection of the X-ray star Sco X-I. During this time we have moved from the detection of a handful of the nearest and brightest sources to the detailed study of the nature of stellar sources in the farthest reaches of our own galaxy and in external galaxies of the local group. The detection of pulsating X-ray sources in bi nary systems permits the measurement of pulsation periods, and orbital parameters with precisions comparable to any yet achieved with traditional observational techniques. The strong indications that most X-ray sources are extremely compact objects give us confidence that X-ray astronomy will playa significant and possibly decisive role in the study of stars near the end point of stellar evolution.
Author : R. Giacconi
Publisher : Springer Science & Business Media
Page : 456 pages
File Size : 42,22 MB
Release : 2012-12-06
Category : Science
ISBN : 9401021058
It was about fourteen years ago that some of us became intrigued with the idea of searching the sky for X-ray and gamma-ray sources other than the Sun, the only celestial emitter of high-energy photons known at that time. It was, of course, clear that an effort in this direction would not have been successful unless there occurred, somewhere in space, processes capable of producing high-energy photons much more efficiently than the processes responsible for the radiative emission of the Sun or of ordinary stars. The possible existence of such processes became the subject of much study and discussion. As an important part of this activity, I wish to recall a one-day conference on X-ray astronomy held at the Smithsonian Astrophysical Observatory in 1960. The theoretical predictions did not provide much encouragement. While several 'unusual' celestial objects were pin-pointed as possible, or even likely, sources of X-rays, it did not look as if any of them would be strong enough to be observable with instru mentation not too far beyond the state of the art. Fortunately, we did not allow our selves to be dissuaded. As far as I am personally concerned, I must admit that my main motivation for pressing forward was a deep-seated faith in the boundless re sourcefulness of nature, which so often leaves the most daring imagination of man far behind.
Author : Richard James Borken
Publisher :
Page : 304 pages
File Size : 44,50 MB
Release : 1973
Category :
ISBN :
Author :
Publisher :
Page : 378 pages
File Size : 39,7 MB
Release : 1973
Category : Orbiting astronomical observatories
ISBN :
Author : Columbia University
Publisher :
Page : 72 pages
File Size : 16,44 MB
Release : 1975
Category :
ISBN :
Author : Vincent Smedile
Publisher :
Page : 0 pages
File Size : 34,73 MB
Release : 2023
Category :
ISBN :
Historically, the Cygnus Loop has been observed in multiple pointings and either large field of view soft X-ray instruments with poor resolution or highly resolved instruments that boast only moderate fields of view of 1 sqaure degree or less. I present both a source model for the Cygnus Loop Supernova Remnant (Cygnus Loop SNR) and the potential spectra recorded by the Rocket for Extended-source X-Ray Spectroscopy (tREXS), which is a sounding rocket with experimental optics created at Penn State. Given the expected timescales for the SNR. The source model is a two-temperature Non-equilibrium Ionization model. The model presented has a reduced chi-sqaure of 1.502. Despite an attempt to fit a Non-equilibrium Ionization and Collisional Ionization Equilibrium model, the two-temperature Non-equilibirum Ionization model proved to fit best. The spectra used for this model were taken from a single 3-degree diameter pointing by HaloSat using the SDD38 and SDD54 detectors. The resulting source model was then treated as a source spectra and run through a ray-tracing instrument simulation model of tREXS to determine what the tREXS optic would observe in the field. The instrument model yielded a high-resolution spectrum, particularly around the lower wavelengths, with strong predicted transition lines at O VII, O VIII, N VII, and C VI. The model predicts a high-intensity ratio between O VII and O VIII, as well as depletions for C, N, and O abundances. Cygnus Loop currently has yet to have a soft X-Ray observation that encompasses the full width of the SNR with a single pointing. These models provide new insight into what a full 3-degree diameter field of view observation of Cygnus Loop SNR with tREXS is and bolster predictions for the spectral observations made by the novel passive focuser optic the rocket employs.
