Ed,
I have been in discussions with Kees and Bogdan about developing a neutron detector. This is approx. a 6 month project, although we may have an early version before that. If there are tests in the 4 to 6 month time frame, we would be interested in placing detectors in.
I don't have detailed kinematics, angle, and/or beam energy requirements. We would work with whatever setup is available. We would choose between two types of reactions: d(e,e'n) where the neutron energy and angle are correlated, and d(e,pn) where the virtual photon is almost real and the electron goes at zero degrees. In one case we set up the neutron detector on the E side and the other we set up on the H side.
We would need a large shielded enclosure in which to place our detectors, and the option of putting anywhere from a few millimeters of iron(steel) to a few centimeters of lead. (Start with the heavy shielding and work down to the thin plates.) The shielding on 5 sides should be at least a cm or more of iron surrounded by 5 to 10 cm of lead or equivalent. The iron cuts down the lead x-rays and (in principle) provides magnetic shielding. I think one meter square, maybe two meters long, would be good. We want to try different flight path lengths, so it should be more or less convenient to move around if possible.
The timing tests we want to perform push the state of the art. We would need both local and remote CAMAC (for constant fraction discriminators) and FASTBUS (for TDC and ADC). We would like to compare relative performance of local and remote electronics (although this could be done off-line, if we can confirm on line I would be happy).
We would want to use the beam pulse synchronization for our timing starts. I believe that exists.
I will know more about the dimensions, thicknesses and locations once Pavel provides background calculations. I asked for some background calculations, but haven't heard back.
I think it would be natural to coordinate this test with tests from another third arm group.
Bill
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