Colleagues,
In response to Eddy's request. Presently, the top of the platform is 8 feet (243.84 cm)) above the floor and 2 feet (60.1 cm) below the beam line. The beam line is 10 feet(304.8 cm) from the Hall A floor. Wheels will be added to the base of the platform so that we can push it around using the forklift.(This will change the height.) Presently, you have to lift it with the crane to move it around. The areal dimensions of the top are 6 feet by 6 feet (182.9 x 182.9 cm2). I am not sure of the minimum distance from the target. Its around 1.5 to 2 meters. Since one edge is cantilevered over the support so that you can get this close, you can not put more than 300 pds of shielding in that position. When the final dimensions, after adding the wheels, are determined. I will email or fax more accurate specs. including a more precise closest approach distance.
My present plans are as follows:Hall A moved the platform to about 135 degrees on the hadron side of the beam line at about 3 meters from the target. On Nov 18 and 19'th we will mount three scintillators 1 x 10 x 10 cm3; 10 x 10 x 30 cm3; 10 x 10 x 30 cm3 colinearly with shielding. We are bringing a NIM bin and some electronics from UVA and will set this up in the Hall A counting house so that we can look at signals, calibrate with cosmics, set thresholds and use a qvt to take data. We will have provision to take concidence between scintillators in order to determine what is coming directly from the target and also to vetoe out charged particles. We will measure the count rate as a function of the thresholds under different beam conditions, which will be dictated by the experiment since we still are parasitic. This should all be set up by the time the hall closes to start up the scheduled experiment. This work is being carried out by UVA, Tel Aviv personnel and Bogdan. Anybody around to help with putting the detectors on the top of the stand and putting shielding around it next tuesday and wednesday are welcome. We will start tuesday morning at 8:00 am.
The next step will depend on the outcome of these test.
Your suggestions are welcome.
Regards, Richard Lindgren
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