Convection Cell
from Peter Dolph, Al Tobias, Gavalya
email 1
As a first step toward A1N target development, it was agreed to produce two (2) prototype all glass cells of convection style. As a first step toward a prototype design, I am sending you some preliminary drawings. The first drawing contains nominal dimensions of our current convection cell. The second and third drawings show a cell with larger pumping chamber and larger target chamber, respectively.
1) Can a convection cell of dimensions shown in the first drawing fit into
the JLab target oven?
2) What is the largest pumping chamber the current JLab target oven can
handle?
3) We may want to extend the length of the transfer tubes, so that the
distance between the pumping chamber and target chamber is greater than
the amount shown in all of the attached drawings. What limit would be
imposed given the current JLab target?
I've attached 3 drawings for the convection cell. The first is the same drawing that was sent to Mike 2.5 years ago. The next two have slight modifications (a larger PC and a larger TC).
Here are a few more views to help. The largest unobstructed opening (window) is 3.13 inches. The target was angled at about 41 degrees to allow vertical pumping (EPR_COIL_IN_OVEN_SECTION_CUT attached) so moving the target in line with the oven requires moving the support over with respect to the design position. We may not have space to do this. There are probably more considerations to be found in the future.
http://www.jlab.org/~zwzhao/polhe3/ccell
from Yi Qiang
The designs are pretty good to me. I'm thinking about another variation with narrower transfer tube for the wall effect. The inside dimension of the current oven which holds the pumping chamber is 6.4 inch (W) x 6.4 in (L) x 7.0 in (H). The side windows which allow laser passing through are 3.8 inch in diameter, they are horizontally centered on each side, and vertically, their centers are 2.625 inch above the bottom of the volume. So in principle it should be large enough to hold all your designs with maximum 2 inch pull-offs, but the room for the laser spot is really tight. Also, a new bottom piece needs to be designed to mount the new cells. More drawings of the current oven and the Transversity/d2n cells can be found here: http://www.jlab.org/~esp/Transversity/Target_Ladder_with_Oven_Rev-/CS85_Oven_Assy_RevC/
