Design of an interaction region with head-on collisions for the ILC

Journal article

An interaction region (IR) with head-on collisions is considered as an alternative to the baseline configuration of the International Linear Collider (ILC) which includes two IRs with finite crossing-angles (2 and 20 mrad). Although more challenging for the beam extraction, the head-on scheme is favoured by the experiments because it allows a more convenient detector configuration, particularly in the forward region. The optics of the head-on extraction is revisited by separating the e+ and e- beams horizontally, first by electrostatic separators operated at their LEP nominal field and then using a defocusing quadrupole of the final focus beam line. In this way the septum magnet is protected from the beamstrahlung power. Newly optimized final focus and extraction optics are presented, including a first look at post-collision diagnostics. The influence of parasitic collisions is shown to lead to a region of stable collision parameters. Disrupted beam and beamstrahlung photon losses are calculated along the extraction elements.

Authors: Appleby, R; Angal-Kalinin, D; Jackson, F; Alabau-Pons, M; Bambade, P

• Publisher: European Physical Society Accelerator Group (EPS-AG)
• Journal: Conf.Proc.C
• Volume: 060626
• Pages: 682-684
• Publication date: 2006-09-28
• Language: English
• Keywords: physics.acc-ph