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Advantages of axially aligned crystals used in positron production at future linear colliders

X. Artru·R. Chehab·M. Chevallier·V. Strakhovenko
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Abstract

The characteristics of the electron-photon showers initiated by 2 to 10 GeV electrons aligned along the <111>-axis of tungsten crystals are compared with those for the amorphous tungsten . In this energy range, as known, the positron yield at the optimal target thicknesses is larger in a crystal case only by several percent. However, the amount of the energy deposition in a crystal turns out to be considerably (by 20 - 50 %) lower than in an amorphous target providing the same positron yield, while the peak energy-deposition density is approximately of the same magnitude in the both cases.

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X. Artru, R. Chehab, M. Chevallier, V. Strakhovenko. 2003-07-03. Advantages of axially aligned crystals used in positron production at future linear colliders. https://doi.org/10.1103/physrevstab.6.091003

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