Author: A.W. Saenz
Publisher: Springer Science & Business Media
ISBN: 3642511856
Category : Science
Languages : en
Pages : 246
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Book Description
Energetic electromagnetic radiation finds frequent uses in science (e. g. , for expe riments in nuclear and elementary - particle physics), in technology (for materials testing), and in medicine (for medical X-rays). The most common method of genera ting such radiation is via the process of "bremsstrahlung" (a German term coined by A. Sommerfeld, meaning "braking radiation") in which a beam of electrons is direc ted into matter (e. g. , a metal target), losing energy during its collisions with the atoms and releasing this energy in the form of emitted radiation. The character of such radiation may be drastically changed by the use of a tar get with periodic structure (most commonly, a crystal target). The coherent waves emitted from individual crystal atoms interfere with each other, monochromatizing and polarizing the radiation and often increasing its intensity manifold, thereby creating a powerful radiation source of high quality for purposes of scientific and technical applications. This is true both for the well - established "coherent bremsstrahlung" process in which the interfering radiation is emitted while the electrons cross a succession of crystal planes, as well as for the more recently discovered process of "channeling radiation" (generating radiation of even higher intensity, but lower energy) in which the radiation is emitted while the electrons propagate along a crystal plane, or a crystal axis, in an oscillatory fashion.
Author: A.W. Saenz
Publisher: Springer
ISBN: 9783642511875
Category : Science
Languages : en
Pages : 235
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Book Description
Energetic electromagnetic radiation finds frequent uses in science (e. g. , for expe riments in nuclear and elementary - particle physics), in technology (for materials testing), and in medicine (for medical X-rays). The most common method of genera ting such radiation is via the process of "bremsstrahlung" (a German term coined by A. Sommerfeld, meaning "braking radiation") in which a beam of electrons is direc ted into matter (e. g. , a metal target), losing energy during its collisions with the atoms and releasing this energy in the form of emitted radiation. The character of such radiation may be drastically changed by the use of a tar get with periodic structure (most commonly, a crystal target). The coherent waves emitted from individual crystal atoms interfere with each other, monochromatizing and polarizing the radiation and often increasing its intensity manifold, thereby creating a powerful radiation source of high quality for purposes of scientific and technical applications. This is true both for the well - established "coherent bremsstrahlung" process in which the interfering radiation is emitted while the electrons cross a succession of crystal planes, as well as for the more recently discovered process of "channeling radiation" (generating radiation of even higher intensity, but lower energy) in which the radiation is emitted while the electrons propagate along a crystal plane, or a crystal axis, in an oscillatory fashion.
Author: P. Sprangle
Publisher:
ISBN:
Category :
Languages : en
Pages : 48
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Book Description
In recent years, there has been considerable renewed interest in the development of novel devices for the production of high power coherent electromagnetic radiation. This interest has been motivated largely by the realization that, with existing technology, certain processes utilizing relativistic electron beams can produce coherent electromagnetic radiation at power levels far in excess of those achieved by conventional electron devices. This paper will review the current status of this rapidly developing field, with emphasis on two generic devices. The major thrust in the recent development of electron beam driven radiation sources has been directed towards achieving shorter wavelengths, greater power and higher efficiencies. Shortly after the development of such successful sources as the magnetron, kylstron and various traveling wave devices, it became clear that, in their original form, they were limited in their ability to produce high levels of radiation efficiently at short wavelengths. To circumvent the inherent limitations of these conventional coherent radiation sources, many new concepts and mechanisms, as well as variations on conventional concepts, were proposed. This paper is concerned primarily with two devices which are, relatively speaking, newcomers to the list of coherent classical radiation sources. They are the free electron laser and the cyclotron resonance maser (CRM); one well known type of CRM is the gyrotron.
Author: כרן פרדכן-כשי
Publisher:
ISBN:
Category :
Languages : iw
Pages : 214
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Book Description
Author: Keren Fradkin-Kashi
Publisher:
ISBN:
Category :
Languages : en
Pages : 107
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Book Description
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 5
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Book Description
Higher frequency radiation sources and their detectors have many potential uses--especially if they are compact, variable, efficient and have high brightness. We discuss some possibilities together with various impediments to their realization. The differences between bound and free electrons are studied from the standpoint of the frequencies that are practicably achievable. With the ansatz that the transport physics with Maxwell's Equations are valid but modified by the material properties, a number of analogs exist between these two basic sources of radiation. In many cases, the differences are between macro and micro implementations e.g. between klystrons and klystrinos (micro or nano) or solid state and semiconductor lasers or rare-earth doped transistors. Cases with no apparent analogs are ones due to unique quantum effects e.g. radiation at 3 kT{sub c} in superconductors. This is well above magnetic resonance imaging MRI around 0.4 meV but well below room temperature at 25 meV. Bound and free possibilities for planar, micro undulators over this range are studied using FDTD techniques. To our knowledge, there have been no implementations of either possibility.
Author: Chi Keng Chen
Publisher:
ISBN:
Category : Particles, Relativistic
Languages : en
Pages : 218
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Author: Wolfram Helml
Publisher:
ISBN:
Category :
Languages : en
Pages : 126
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Author: Majid Ebrahim-Zadeh
Publisher: Springer Science & Business Media
ISBN: 140206439X
Category : Science
Languages : en
Pages : 630
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Book Description
Covering fundamental principles and the state of the art, this is a collection of reviews from experts in mid-infrared (mid-IR) coherent sources. Among the sources covered are optical parametric oscillators, difference frequency generators, and the most recent broadband crystalline, quantum cascade, and fiber lasers. The authors show how advances in mid-IR science and technology make these sources indispensable for a variety of applications.
Author: Chi Keng Chen
Publisher:
ISBN:
Category :
Languages : en
Pages : 109
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Book Description
