2011/03/07

Piecing Together the Source Holder

Figure 1: From left to right: lead disk of thickness 0.063“ and diameter 0.375”; Am-241 source of activity 1 μCi; Al foil to block alpha particles; lead disk with 0.008“ (0.2 mm) diameter hole for collimation; pin to hold lead disk in place as hole for collimation is off-centre; and copper can to hold source.

Figure 2: Four Am-241 sources in their housings, all of activity 1 μCi.

Figure 3: Am-241 sources attached to plate, which in turn is attached to the source holder body

Figure 4: Thermometer attached to spare source holder plate

Crystal Inspection

Figure 5: Large scratch on electrode side. Initially caught us by surprise, but noticed that this has been documented in detector elog entry 1343. Slight scratch seen 60°-90° to the left of the more prominant one, across outermost electrode. Wire bonds look intact.

Tower Assembly

Figure 6: Connect spool to crystal. Bottom lid was reattached prior to this procedure.

Figure 7: Remove bottom lid and attach source holder. Cover with bottom lid. Secure with threaded rods (not shown).

Figure 8: Orientation of Schuba extender plugs looks correct on left, but pins miss holes due to lip on tower.

Figure 9: Confirmation that Schuba extender plugs should be orientated as shown in left image of Figure 8.

Figure 10: Wait! Things are not so simple. Both orientations cannot be attached to the side coax. The protectors on the side coax in the right image can be removed, but this will allow the channels to come into contact with the schuba connector, thus shorting them to ground.