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arXiv · 1301.1222

Positron Source Simulations for ILC 1 TeV Upgrade

Andriy Ushakov·Gudrid Moortgat-Pick·Sabine Riemann·Wanming Liu·Wei Gai
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Abstract

The generation and capture of polarized positrons at a source with a superconducting helical undulator having 4.3 cm period and 500 GeV electron drive beam have been simulated. The positron polarization has been calculated for the different undulator K values (up to K = 2.5). Without applying a photon collimator, the maximal polarization of positrons is about 25% for 231 meters active magnet length of undulator with K = 0.7. Using an undulator with K = 2.5 and a collimator with an aperture radius of 0.9 mm results in increase of positron polarization to 54%. The energy deposition, temperature rise and stress induced by high intense photon beam in the rotated titanium-alloy target have been estimated. The maximal thermal stress in the target is about 224 MPa for the source with photon collimation to achieve a positron polarization of 54%.

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Andriy Ushakov, Gudrid Moortgat-Pick, Sabine Riemann, Wanming Liu, Wei Gai. 2013-01-07. Positron Source Simulations for ILC 1 TeV Upgrade. https://arxiv.org/abs/1301.1222

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