At Stu's request, I calculated the dependence on
positron bunch current of electron lattice functions and dynamic
apertures for our present operating conditions of
t1-4 positrons on t5-9 electrons at 10 mA/bunch
and compared them to the 8x5 "colliding" case
with 5 mA/bunch.  The electron tunes are held constant wrt positron
bunch current by qtuning the simulation.

4x5 lattice function:
http://www.lns.cornell.edu/~critten/cesr/injection/notes/15may06/bunch_1288

4x5 dynamic aperture:
http://www.lns.cornell.edu/~critten/cesr/injection/notes/15may06/dynap_1288



8x5 lattice function:
http://www.lns.cornell.edu/~critten/cesr/injection/notes/15may06/bunch_1287

8x5 dynamic aperture:
http://www.lns.cornell.edu/~critten/cesr/injection/notes/15may06/dynap_1287


The 8x5 vertical dynamic aperture is smaller (0.35 mm vs 0.55 mm).
The 8x5 horizontal aperture is slightly larger (3.0 mm vs 2.5 mm).


-- jim

========================================================
James Crittenden                   Tel. (607) 255-9424
Wilson Synchrotron Laboratory      Fax  (607) 255-8062
Cornell University
Ithaca, New York 14853-8001
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