T9 test setup at Daresbury was powered up and noise levels were checked using a pulser peak.
A 1V peak was used. For most channels this corresponded to a peak position at around +-11000 from the zero point at 9000.
An example of this is shown in attachment 1 showing the peak in nnaider 11, ASIC 4, ADC 11.
It was also observed that for both nnaider 11 and 12 (FEE modules corresponding to negative signals) that channels 2, 56 and 59 were not contributing to the rate. See attachment 2.
Upon investigating the missing channels ADC spectra the only apparent issue appeared in nnaida 11 ASIC 4, ADC 8. Which is plot 4.7.L. Here we see the peak much higher coming in at around channel 63000. See attachment 3.
The remaining missing channels in the rate plot appear to have normal amplitudes with maybe slightly higher noise. FWHM of ~60 as oppposed to ~18. Discussed more below.
Also done was a noise measurement across the all the ASICs. To do this an ADC was chosen belonging to each of the ASICs and the pulser peak location and FWHM was recorded. The reaults are as shown below.
FEE# ASIC/ADC Centroid Location FWHM
11 1.8 42951 19.38
11 2.8 41012 17.48
11 3.8 41929 20.01
11 4.8 41302 17.88
12 1.8 41830 17.38
12 2.8 41119 16.01
12 3.8 42669 18.30
12 4.8 41811 15.21
13 1.8 24329 15.05
13 2.8 24034 13.64
13 3.8 24209 15.79
13 4.8 24607 13.29
14 1.8 24650 16.19
14 2.8 24618 14.12
14 3.8 23934 15.04
14 4.8 22584 14.36
14 4.8 22584 14.36
It was seen that the noise was fairly low which is to be expected as there were no dtectors connected and only a short length of kapton cables connected to the board. |