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Chan, J.L.H.
Stanford Univ., CA (USA)1977
Stanford Univ., CA (USA)1977
AbstractAbstract
[en] The use of energy spectral information in radiologic measurements was investigated. The energy spectral characteristics of bremsstrahlung radiations filtered by the K-edge absorption of an element were studied by developing suitable models of the filtered spectra. Using the models, the measurement errors caused by the polyenergetic nonlinearity, when such radiations were used as pseudomonoenergetic sources, were investigated. The measurement errors were found to be minimal and simple correction methods were available. A performance criterion was established to determine the optimal energies for measurements. The measurement errors caused by noise from electronic systems and also from limited data accuracies were studied. The noise effects from different types of noise were compared, the effects were shown to be similar and energy values could be chosen so that they were optimal to all types of noise discussed. The optimal energies were also found to be obtainable from a wide variety of filter materials. After the efficacy of the filtered radiations and the determination of the optimal energies were investigated, the rest of this dissertation dealt with the implementation of the measurements. Since radiographic films are the normal recording device in the clinic, their use as detectors and recorders in our measurements was studied
Source
1977; 101 p; University Microfilms Order No. 78-02,143; Thesis (Ph. D.).
Record Type
Report
Literature Type
Thesis/Dissertation
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INIS IssueINIS Issue
AbstractAbstract
[en] The internal bremsstrahlung spectra from the β decay of 185W and 32P were measured using a NaI(Tl) scintillation spectrometer with a standard geometrical arrangement. After making all the necessary corrections the experimental results are compared with the allowed theory of the Knipp, Uhlenbeck, and Bloch (KUB theory) and also with the Coulomb corrected theories of Lewis, Ford, and Nilsson. In the case of 185W it is found that from 78 to 200 keV the experimental distribution is in good agreement with the KUB theory whereas beyond 200 keV and below 78 keV the experimental points are far above even the highest Coulomb corrected theoretical distribution of Nilsson. The internal bremsstrahlung from this isotope has not been previously investigated. In the case of 32P the experimental relative intensity spectrum is compared with the KUB theory and also with the Coulomb corrected theory of Lewis and Ford. Fairly good agreement is obtained from 30 to 200 keV with the KUB theory but in the energy region from 200 to 900 keV, the experimental results deviate positively from both the KUB and Lewis and Ford theories. The experimental excess over the Lewis and Ford theory is 15% on the average
Primary Subject
Record Type
Journal Article
Journal
Phys. Rev., C; v. 13(3); p. 1267-1276
Country of publication
BASIC INTERACTIONS, BETA DECAY, BETA DECAY RADIOISOTOPES, BETA-MINUS DECAY RADIOISOTOPES, DAYS LIVING RADIOISOTOPES, DECAY, ELECTROMAGNETIC RADIATION, EVEN-ODD NUCLEI, HEAVY NUCLEI, INTERACTIONS, ISOMERIC TRANSITION ISOTOPES, ISOTOPES, LEPTONIC DECAY, LIGHT NUCLEI, MINUTES LIVING RADIOISOTOPES, NUCLEI, ODD-ODD NUCLEI, PARTICLE DECAY, PHOSPHORUS ISOTOPES, RADIATIONS, RADIOISOTOPES, TUNGSTEN ISOTOPES, WEAK INTERACTIONS
Reference NumberReference Number
INIS VolumeINIS Volume
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AbstractAbstract
[en] The internal bremsstrahlung spectrum accompanying the non-unique second-forbidden β-decay of 36Cl is measured using the magnetic deflection technique. The true IB spectrum is obtained with the help of the inverse of the detector response matrix. The experimental data in the energy interval 80 to 700 keV are compared with the theoretical spectra of Knipp and Uhlenbeck, and Bloch, Lewis and Ford, and Chang and Falkoff. The agreement between the measurement and theory is not good throughout the energy region of the present investigation, though the experimental points are close to the second-forbidden scalar theory of Chang and Falkoff. (Auth.)
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Record Type
Journal Article
Journal
Nuclear Physics. A; v. 289(1); p. 54-60
Country of publication
BASIC INTERACTIONS, BETA DECAY RADIOISOTOPES, BETA-MINUS DECAY RADIOISOTOPES, CHLORINE ISOTOPES, DECAY, ELECTRON CAPTURE RADIOISOTOPES, ENERGY-LEVEL TRANSITIONS, INTERACTIONS, ISOTOPES, LEPTONIC DECAY, LIGHT NUCLEI, NUCLEI, ODD-ODD NUCLEI, PARTICLE DECAY, RADIOISOTOPES, WEAK INTERACTIONS, YEARS LIVING RADIOISOTOPES
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] A qualitative discussion is given of some important features of the radiation from channeled electrons and positrons, with particular emphasis on the relation to coherent bremsstrahlung (the 'Ueberall effect'). (orig.)
Source
8. international conference on atomic collisions in solids; Hamilton, Canada; 13 - 17 Aug 1979
Record Type
Journal Article
Literature Type
Conference; Progress Report
Journal
Nuclear Instruments and Methods; ISSN 0029-554X;
; v. 170(1-3); p. 1-5

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INIS VolumeINIS Volume
INIS IssueINIS Issue
Tippmann, Marc; Knoetig, Max; Appel, Simon; Beischler, German; Kaindl, Jill; Lewke, Timo; Meindl, Quirin; Moellenberg, Randolph; Oberauer, Lothar; Pfahler, Patrick; Prade, Ludwig; Stempfle, Tobias; Winter, Juergen; Zimmer, Vincenz
AGUNA-LENA working group2013
AGUNA-LENA working group2013
AbstractAbstract
[en] LENA (Low Energy Neutrino Astronomy) is a next-generation liquid-scintillator neutrino detector with 50kt target mass. The broad spectrum of physics goals ranging from the sub-MeV to the GeV regime sets high demands on the photosensors. Currently, photomultipliers (PMTs) are the sensor of choice. However, besides detecting photons, they also emit light through bremsstrahlung or fluorescence induced by the electron avalanche in the dynode chain, which can produce further pulses in the same PMT or adjacent sensors. In order to study these effects and their connection to afterpulses occurring in the PMT, measurements of light emission and fast afterpulses have been carried through in collaboration with the CTA project. Both bremsstrahlung and fluorescence have been observed, with the first also being the origin of a type of fast afterpulses.
Primary Subject
Source
77. Annual meeting with ordinary general meeting of the DPG and 2013 Spring meeting with the divisions hadrons and nuclei, particle physics, the working teams equal opportunities, energy, the working groups information, young DPG, philosophy of the physics, physics and disarmament; 77. Jahrestagung der DPG mit Ordentlicher Mitgliederversammlung und DPG-Fruehjahrstagung 2013 mit den Fachverbaenden Physik der Hadronen und Kerne, Teilchenphysik den Arbeitskreisen Chancengleichheit, Energie den Arbeitsgruppen Information, junge DPG, Physik und Abruestung; Dresden (Germany); 4-8 Mar 2013; Available from http://www.dpg-verhandlungen.de; Session: T 109.6 Mo 18:05; No further information available; Also available as printed version: Verhandlungen der Deutschen Physikalischen Gesellschaft v. 48(2)
Record Type
Journal Article
Literature Type
Conference
Journal
Verhandlungen der Deutschen Physikalischen Gesellschaft; ISSN 0420-0195;
; CODEN VDPEAZ; (Dresden 2013 issue); [1 p.]

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External URLExternal URL
Voss, K.E.; Fisch, N.J.
Princeton Univ., NJ (United States). Plasma Physics Lab. Funding organisation: USDOE, Washington, DC (United States)1991
Princeton Univ., NJ (United States). Plasma Physics Lab. Funding organisation: USDOE, Washington, DC (United States)1991
AbstractAbstract
[en] For certain predominantly one-dimensional distribution functions, an analytic inversion has been found which yields the velocity distribution of superthermal electrons given their Bremsstrahlung radiation. 5 refs
Primary Subject
Secondary Subject
Source
Oct 1991; 4 p; CONTRACT AC02-76CH03073; OSTI as DE92001937; NTIS; INIS; US Govt. Printing Office Dep
Record Type
Report
Report Number
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] Usually the triennial control of radiation protection devices such as survey meters are made by using radioactive sources for instance a Cs"1"3"7 source set at various distances to get a range of dose rates. A new method that does not use radioactive source has been developed, this method uses the Bremsstrahlung radiation emitted by an electron beam passing through a solid target. The photons that form the Bremsstrahlung radiation are emitted with a broad continuous spectrum of energy that can cover all the application domain of a survey meter. The proportional relationship between the dose rate of the photon beam and the intensity of the primary electron beam allows the measurement of the survey meter's response to the whole dose range by only acting on the parameters of the electron accelerator, no more need to move the survey meter or the radioactive source. (A.C.)
Original Title
Verification de l'etalonnage de radiametres, sans sources radioactives
Primary Subject
Source
2 refs.
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Journal Article
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AbstractAbstract
[en] The spectral intensity of bremsstrahlung from a pair plasma is calculated with fluctuation theory and particle orbit theory. The predictions given by the two theories agree with each other in the low frequency region. However, the fluctuation theory gives invalid results in the high frequency region because of the failure of the assumption made in the theory. Particle orbit theory shows that in the high frequency region the spectral intensity of bremsstrahlung from a pair plasma depends on the radiation frequency ω through the exponential factor exp(-ℎω/2T), where T is the plasma temperature.
Primary Subject
Source
S0741-3335(08)90644-8; Available from http://dx.doi.org/10.1088/0741-3335/50/12/125004; Country of input: International Atomic Energy Agency (IAEA)
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Journal Article
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Iwamoto, Naoki
Funding organisation: United States (United States)2001
Funding organisation: United States (United States)2001
AbstractAbstract
[en] The energy-loss rates of degenerate neutron-star matter due to thermal bremsstrahlung of pseudoscalar particles and axions via neutron-proton collisions together with the mean-free path and the energy spectrum from neutron-neutron, neutron-proton, and neutron-neutron processes are calculated. Analytic expressions for these quantities are obtained in the general case where the pseudoscalar particle couples to the proton and neutron with different strengths and the protons and the neutrons have different Fermi momenta. These rates are compared with those of other authors
Primary Subject
Source
Othernumber: PRVDAQ000064000004043002000001; 063112PRD
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Journal Article
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AbstractAbstract
[en] Using an electron-atom crossed beam apparatus, free from solid-state effects, dependence of the position of maximum in the measured angular distributions of bremsstrahlung induced by 3 to 15 keV electron bombardment of argon, krypton and xenon has been investigated as a function of incident electron energy, atom number and observed photon frequency. While calculations of Tseng et al and of Sommerfeld serve as good descriptions of angular distribution of bremsstrahlung, both theories over estimate the position of the maximum intensity. (author)
Secondary Subject
Record Type
Journal Article
Journal
Doga Bilim Dergisi. Seri: A1; CODEN DBAME; v. 9(2); p. 105-112
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