Log entry time 01:32:32 on October 01, 2010

Entry number 333278

Followups:

• 333280 10/01/10 01:55 efuchey Compton rates: beam in chicane 2

Here is what I did. I put the detector at lowest vertical position, and lift it up, step by step, while HV applied and coda running, to observe the counting rates. I did it for HV = 1400 V (Fig 1), 1500 V (Fig 2), 1600 V (Fig 3), and 1650 V (Fig 4). For the highest voltage applied to the PMT (1650 V), the rates are about 1e3 Hz, whereas they're at about 1e2 Hz for the lowest voltage (1400 V). Again, I did not dare going further than 1650 V.

Figure 1

Figure 2

Figure 3

Figure 4