Summary
This work presents a general quantitative description of the bremsstrahlung linear polarization on the basis of original experimental data and available theoretical calculations. The results give the dependence of the polarization ona) the initial electron kinetic energy,T 0, in a range from 10−2 to 103 MeV,b) the photon energy in a range from 0.1T 0 toT 0,c) the photon emission angle in a range from 0 to 180 degrees, andd) the atomic number of the target in a range from 4 to 79. The experimental data were obtained for a range of electron energies from 0.05 to 1.0 MeV with beryllium, aluminum, and gold targets. Theoretical estimates of the polarization were calculated from the Sommerfeld-Kirkpatrick-Wiedmann results for the non-relativistic energy region, the Olsen-Maximon results for the extreme relativistic energy region, and the Gluckstern-Hull (Born approximation) results for the intermediate energy region. Final results are expressed in terms of the peak polarization and the corresponding peak angle as a function of the electron and photon energies, and best estimates of the polarization are given on the basis of the combined experimental and theoretical data.
Riassunto
Nel presente lavoro si espone una descrizione quantitativa generale della polarizzazione lineare di bremsstrahlung sulla base dei dati sperimentali originali e dei calcoli teorici disponibili. I risultati danno la dipendenza della polarizzazione da:a) l’energia cinetica iniziale dell’elettrone,T 0, nel campo da 10−2 a 103 MeV;b) l’energia dei fotoni nel campo fra 0.1T 0 eT 0;c) l’angolo di emissione dei fotoni nel campo fra 0° e 180°, ed) il numero atomico del bersaglio nel campo fra 4 e 79. I dati sperimentali sono stati ottenuti per una zona di energie dell’elettrone da 0.05 a 1.0 MeV con bersagli di berillio, alluminio ed oro. Le valutazioni teoriche della polarizzazione furono dedotte dai risultati di Sommerfeld-Kirkpatrick-Wiedmann per la regione non-relativistica di energia, dai risultati di Olsen-Maximon per la regione relativistica estrema, e dai risultati di Gluckstern-Hull (approssimazione di Born) per la regione intermedia. I risultati finali sono espressi in termini della polarizzazione di picco e il corrispondente angolo di picco come funzione delle energie dell’elettrone e del fotone, e le migliori valutazioni della polarizzazione sono espresse sulla base dei risultati sperimentali e teorici combinati.
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Motz, J.W., Placious, R.C. Bremsstrahlung linear polarization. Nuovo Cim 15, 571–598 (1960). https://doi.org/10.1007/BF02724990
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DOI: https://doi.org/10.1007/BF02724990