<p>Performed pulser measurements with test setup at Daresbury lab, with main purpose of remembering how to operate the system! The status is similar to what Chris observed in Elog entry #14. Confirmed ASIC settings as in entry#4 of elog.</p>
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<div>The pulser spectra shows FWHM of ~ 13.5 ch for all FEE64 cards with no DSSD connected to the system (i.e. Kapton cables unplugged). Some channels in a few FEE64 cards show two peaks on the pulse spectra, but still narrow and only slightly wider distribution for the two peak combined (~ 15 ch, see Figure 1).</div>
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<div>With the DSSD connected, the pulser spectra shows a double peak structure with FWHM ~ 250 ch for each peak (Figure 2). </div>
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<div>However, for NNAIDA#11 and #12 a few ASICs had high level of noise, and were therefore used in the 1GeV range to become quiet (ASIC3 for nnaida#11, ASIC1 and 2 for nnaida#12). Figure 3 and 4 show sample of these noisy channels.</div>
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<div>A good question brought up by Patrick is if the true noise level with a biased DSSD corresponds to these 'noisy' ASICs, or to the ones that are much more quiet (maybe some signal path disconnected for these?). Measurements with a radioactive source could clarify this.</div>
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<div>Figure 1: pulser, no DSSD connected</div>
<div><a href="141024_155940/nnaida13_1.2.L_pulser_noDSSD.png?lb=AIDA"><img border="0" alt="nnaida13_1.2.L_pulser_noDSSD.png" src="141024_155940/nnaida13_1.2.L_pulser_noDSSD.png?lb=AIDA&thumb=1" name="att0" id="att0" /></a></div>
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<div>Figure 2: double peak structure for pulser spectra for NNAIDA13 (similar spectra seen in the other FEE64 cards)</div>
<div> <a href="141024_160035/pulser_nnaida13_sample.png?lb=AIDA"><img border="0" alt="pulser_nnaida13_sample.png" src="141024_160035/pulser_nnaida13_sample.png?lb=AIDA&thumb=1" name="att1" id="att1" /></a></div>
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<div>Figure 3: spectra for NNAIDA#11 with biased DSSD connected, and no pulser signal going into the system (only noise)</div>
<div> <a href="141024_160124/noise_nnaida11_DSSD_sample2.png?lb=AIDA"><img border="0" alt="noise_nnaida11_DSSD_sample2.png" src="141024_160124/noise_nnaida11_DSSD_sample2.png?lb=AIDA&thumb=1" name="att2" id="att2" /></a></div>
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<div>Figure 4: spectra for NNAIDA#12 with biased DSSD connected, and no pulser signal going into the system (only noise)</div>
<div> <a href="141024_160208/noise_nnaida12_DSSD_sample.png?lb=AIDA"><img border="0" alt="noise_nnaida12_DSSD_sample.png" src="141024_160208/noise_nnaida12_DSSD_sample.png?lb=AIDA&thumb=1" name="att3" id="att3" /></a></div>
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