Dear Pavel and the task force,

I've been thinking about background calculations that could help prepare for prototype tests:

I suggest calculations with an intermediate mass target, most target windows are made of similar materials. I suggest aluminum, 200 um =54 mg/cm2. Beam current of 10 uA. (results can be scaled).

I suggest an intermediate energy=2.4 GeV

Let's begin with a "forward" and backward angle: 60 degrees and 120 degrees.

We should consider an unshielded detector surrounded on five sides with heavy shielding with an adjustable layer on the front side. 5 sides are 5 cm lead with 1 cm iron inside, dimensions of 1 m^3.

The front layer is a minimum of 1 mm steel (particles must exit the scattering chamber) Options include adding 2 mm lead; and 2 cm lead.

Distance to detector face: 1 m, 4 m, 20 m. (to explore different regions)

Dimensions of detectors inside: H x W x D (Depth is along particle trajectory from target)

20cm x 100cm x 2cm plastic scintillator (a standard bar)

10cm x 10cm x 60cm plastic scintillator (a neutron block)

16cm x 16cm x 60cm plastic scintilaltor (a big neutron block)

16cm x 16cm x 5cm plastic scintillator (to explore surface vs volume effect in simulation)

We want to calculate for each of the following particles:

photons, electrons, hadrons, neutrons:

rates of energy deposit in the plastic spanning the following ranges 0.01 MeV (if possible, or some number you prefer) up to 1000 MeV in approx 100 logarithmic steps.

You may suggest different/additional choices,


Bill Hersman, Maurik Holtrop

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11/14/97 / Monte Carlo Suggestions - Hersman/ Last Updated 2/26/99