Agenda and Summary:

1) Update on 1.6mrad extraction line for 1TeV CM -- for SLAC-BNL-UK-France taskforce, Yuri Nosochkov
2) Activities and plans towards the MARS-GEANT4 BDIR-SiD interface -- Igor Tropin
3) SLAC RP current activities in radiation simulation and possible extension to ILC -- Alberto Fasso, Noriaki Nakao and Heinz Vincke

Extraction line for 1TeV CM:

Yuri presented the status of extraction line design for 1TeV CM "2mrad IR", being done by the SLAC-BNL-UK-France task force. The present version is actually optimized for 1.6mrad crossing angle. It has FD which is able to go to 1TeV, based on NbTi, and has r=35mm aperture of QD0. The version require further optimization, however. Beam clearance at QEX1 is very tight. Going back to 2mrad (which seem to be possible) will help. The beam profile at secondary focus is distorted due to sextupoles of the extraction line -- need to optimize this further. There are some losses of disrupted beam (~40W) in the case when beams have 100nm offset. Next step would be to modify this version for 2mrad crossing angle. 

Activities and plans towards the MARS-GEANT4 BDIR-SiD interface:

Igor described activities toward simulation the beam delivery - detector interface with the goal to find response of the ILC sub-detectors to background radiation, including both machine-related backgrounds and radiation from the collision point. Tools involved in these simulations are STRUCT, MARS, GEANT4 etc.  The hope is to have first results at Snowmass.

SLAC RP current activities in radiation simulation and possible extension to ILC:

Alberto, Noriaki and Heinz described work performed by SLAC Radiation Physics group for LCLS and NLC and discussed possible tasks for ILC.  The group then engaged in discussion of possible first steps toward this work. Updating the linac models, finding what was done for TESLA design, getting existing civil layouts of linac and beam delivery, studying the needed shielding between IRs, designing the beam containment system which allows people working in one IR while another is running, evaluating RP issues of single vs two tunnels, and many other, are all considered important steps to start from.


Andrei Seryi, 08/03/05