Hi Paul,

We have a similar target for more forward angles.  The length of the current cell is 25cm.  I don't see a problem with extending it another 5 cm.  The cell model is attached.  Obviously the cell block would need to be modified.  The cell has the feature of being 2 cm wide and thus is fairly narrow reducing the amount of D2 that the exiting particles have to pass through.  The cell has vertical flow as well making it suitable for parity experiments.  This cell has a knife edge similar to a ConFlat that is proprietary Target Group design.  Just kidding but it does hold He at inverse pressure over 300 psi.  It also was designed using ASME D2 as much as possible.  I have the calcs somewhere along with our testing.  The cost was reasonable as well.

It sounds like you could use the current target with some minor plumbing modifications and a new cell block.  If the power to the target is low enough that is.  Call me if you need more details.

Dave