Page History

...

to use to align the top and bottom to our best precision.  The drawings indicate

a change of 4.5 mm up when cold.  The tolerance of these drawings is 0.5 mm.

2.) Survey in cave using LN2 in nose and magnet.  This would be a partly
open survey with a special nose put on with transparent windows on either
side for optical survey.  The nitrogen shield and beam widows on the
vacuum are left off for this.  This survey in the cave will be of the
magnet aperture, the target insert along X, Y, Z, and the outside
fiducials (can and top flange and reference locations in the cave). 
Crosshairs will be use in the front and back of the target cell to help
determine degree of twisting in the cell.  Cross hairs in the can windows
can also be use to set the rotational alignment of the can.  The target
insert carbon fiber is not expected to contract very much but the aluminum
ladder can.  The primary goal of this survey is to compare to calculations
of contraction and measure positioning of target cell with respects to
magnet aperture and also with respect to the beamline.  There should be a
hard stop setup on the actuator that positions the top target exactly in
the beam line (to test repeatability of the string potentiometer and gears).

...