View source for Minutes SHMS MC 7

= Minutes of SHMS MC working group meeting 11/15/2011 =

Participants: Dave, Dipangkar, Mark and Peter

1. Mark showed plots that demonstrated why the delta acceptance of the SNAKE and COSY models were looking different 
as observed during the previous meeting. The reason was the difference were the cuts in the detector HUT which were
not being applied in the SNAKE model. Once those cuts are in place, the COSY and SNAKE distributions agree very well. The x at the focal plane agree remarkably well, although at different intermediate apertures in the dipole they can look somewhat different. The y distribution at the FP agree but have an offset of few cm.
(see 

2. Dipangkar showed the plots of focal plane x vs y distributions where the current apertures were compared with the apertures from pre-2006 model. In the pre 2006 model there were no HB apertures, no mechanical entrance and exit for the Quads and dipole apertures were also different. It seems the largest effect is from the Quad mechanical apertures. Without the quad mechanical apertures, the focal place distributions resemble the 2007-2009 distributions we have been trying to reproduce. However, the acceptance is still only about 4.6 msr still smaller than the 5 msr reported during 2007-2009.