<p>21/02/15</p>
<p>1230: Developing the software to check synchronisation between DAQs. Below line runs program on aidas1 - sends data from TapeServer to BELEN.</p>
<p> ./DataRelayFilter -n 10.32.6.196 -p 10307 -I 2</p>
<p>1500: Investigating pulser peak FWHMs as function of bias voltage.</p>
<p> Constant shaping time of 0x3, slow comp thresh 0x20, fast comp thresholds of 0xff. All other setting as standard. Detector MSL BB18 2977-20.</p>
<p> Results summarised in table directly below.</p>
<table width="789" cellspacing="1" cellpadding="1" border="1" height="155">
<tbody>
<tr>
<td width="38"> </td>
<td width="698" valign="middle" align="center" colspan="9">Pulser peak FWHM (ch)</td>
</tr>
<tr>
<td width="38"> </td>
<td width="86"> </td>
<td width="132" align="center" colspan="2">nnaida1</td>
<td width="156" align="center" colspan="2">nnaida3</td>
<td width="164" align="center" colspan="2">nnaida6</td>
<td width="160" align="center" colspan="2">nnaida8</td>
</tr>
<tr>
<td width="38">Bias (v)</td>
<td width="86">Leakage current (uA)</td>
<td width="63">1.9.L</td>
<td width="69">2.10.L</td>
<td width="68">1.9.L</td>
<td width="88">2.9.L</td>
<td width="72">2.10.L</td>
<td width="92">3.11.L</td>
<td width="80">2.10.L</td>
<td width="80">3.9.L</td>
</tr>
<tr>
<td width="38">75</td>
<td width="86">10.700</td>
<td width="63">166</td>
<td width="69">133</td>
<td width="68">174</td>
<td width="88">156</td>
<td width="72">176</td>
<td width="92">168</td>
<td width="80">271</td>
<td width="80">285</td>
</tr>
<tr>
<td width="38">100</td>
<td width="86">10.905</td>
<td width="63">165</td>
<td width="69">131</td>
<td width="68">174</td>
<td width="88">158</td>
<td width="72">168</td>
<td width="92">166</td>
<td width="80">272</td>
<td width="80">285</td>
</tr>
<tr>
<td width="38">125</td>
<td width="86">11.090</td>
<td width="63">167</td>
<td width="69">151</td>
<td width="68">175</td>
<td width="88">158</td>
<td width="72">167</td>
<td width="92">160</td>
<td width="80">271</td>
<td width="80">285</td>
</tr>
<tr>
<td width="38">150</td>
<td width="86">11.410</td>
<td width="63">179</td>
<td width="69">140</td>
<td width="68">178</td>
<td width="88">158</td>
<td width="72">169</td>
<td width="92">166</td>
<td width="80">271</td>
<td width="80">283</td>
</tr>
<tr>
<td width="38">200</td>
<td width="86">12.275</td>
<td width="63">-----</td>
<td width="69">------</td>
<td width="68">175</td>
<td width="88">159</td>
<td width="72">------</td>
<td width="92">------</td>
<td width="80">272</td>
<td width="80">
<p>286</p>
</td>
</tr>
</tbody>
</table>
<p> At bias of -200V nnaida1+6 stopped outputting data but continued to produce SYNCs. Good event rate dropped from ~few thousand per sec to ~300 per sec.</p>
<p> After returning bias to -150V, nnaida1+6 started producing data again. No effect was seen in nnaida3+8.</p>
<p> nnaida8 peaks are not particularly Gaussian in shape. Look more skewed with one rolling edge and one side a relatively sharp drop.</p>
<p> No obvious trends with changing bias voltage. Will return to -100V.</p>
<p>1545: Investigating pulser peak FWHMs as function of shaping time.</p>
<p> Bias returned to -100V, with leakage current 11.000uA.</p>
<p> Settings for all nnaida: slow comp thresh = 0x20, fast comp thresh = 0xff, hold time = 0x4 if shaping time <= 0x8, 0x8 if shaping time > 0x8.</p>
<table width="789" cellspacing="1" cellpadding="1" border="1" height="155">
<tbody>
<tr>
<td width="740" valign="middle" align="center" colspan="9">Pulser peak FWHM (ch)</td>
</tr>
<tr>
<td width="87"> </td>
<td width="144" align="center" colspan="2">nnaida1</td>
<td width="165" align="center" colspan="2">nnaida3</td>
<td width="174" align="center" colspan="2">nnaida6</td>
<td width="170" align="center" colspan="2">nnaida8</td>
</tr>
<tr>
<td width="87">Shaping time (Hex)</td>
<td width="71">1.9.L</td>
<td width="73">2.10.L</td>
<td width="72">1.9.L</td>
<td width="93">2.9.L</td>
<td width="76">2.10.L</td>
<td width="98">3.11.L</td>
<td width="85">2.10.L</td>
<td width="85">3.9.L</td>
</tr>
<tr>
<td width="87">0x0</td>
<td width="71">254</td>
<td width="73">172</td>
<td width="72">151</td>
<td width="93">160</td>
<td width="76">172</td>
<td width="98">164</td>
<td width="85">287</td>
<td width="85">293</td>
</tr>
<tr>
<td width="87">0x1</td>
<td width="71">237</td>
<td width="73">167</td>
<td width="72">176</td>
<td width="93">172</td>
<td width="76">184</td>
<td width="98">176</td>
<td width="85">328</td>
<td width="85">367</td>
</tr>
<tr>
<td width="87">0x2</td>
<td width="71">193</td>
<td width="73">146</td>
<td width="72">184</td>
<td width="93">168</td>
<td width="76">180</td>
<td width="98">175</td>
<td width="85">306</td>
<td width="85">321</td>
</tr>
<tr>
<td width="87">0x4</td>
<td width="71">149</td>
<td width="73">119</td>
<td width="72">171</td>
<td width="93">152</td>
<td width="76">159</td>
<td width="98">155</td>
<td width="85">252</td>
<td width="85">261</td>
</tr>
<tr>
<td width="87">0x8</td>
<td width="71">129</td>
<td width="73">122</td>
<td width="72">154</td>
<td width="93">147</td>
<td width="76">139</td>
<td width="98">137</td>
<td width="85">195</td>
<td width="85">201</td>
</tr>
<tr>
<td width="87">0xb</td>
<td width="71">133</td>
<td width="73">129</td>
<td width="72">160</td>
<td width="93">148</td>
<td width="76">137</td>
<td width="98">135</td>
<td width="85">184</td>
<td width="85">188</td>
</tr>
<tr>
<td width="87">0xf</td>
<td width="71">139</td>
<td width="73">139</td>
<td width="72">169</td>
<td width="93">159</td>
<td width="76">141</td>
<td width="98">142</td>
<td width="85">184</td>
<td width="85">183</td>
</tr>
</tbody>
</table>
<p> Visual 'analysis' suggested 0xb to be the optimal value so used that as shaping time in further tests.</p>
<p> (Graph to follow)</p>
<p>1900: Investigating effect of changes to slow comparator thresholds.</p>
<p> Settings: bias = -100V, hold timing = 0x8, shaping time = 0xb, fast comp thresholds = 0xff. Otherwise, standard settings.</p>
<table width="789" cellspacing="1" cellpadding="1" border="1" height="155">
<tbody>
<tr>
<td width="740" valign="middle" align="center" colspan="9">Position of threshold (ch)</td>
</tr>
<tr>
<td width="87"> </td>
<td width="144" align="center" colspan="2">nnaida1</td>
<td width="165" align="center" colspan="2">nnaida3</td>
<td width="174" align="center" colspan="2">nnaida6</td>
<td width="170" align="center" colspan="2">nnaida8</td>
</tr>
<tr>
<td width="87">Slow comp threshold</td>
<td width="71">1.9.L</td>
<td width="73">2.10.L</td>
<td width="72">1.9.L</td>
<td width="93">2.9.L</td>
<td width="76">2.10.L</td>
<td width="98">3.11.L</td>
<td width="85">2.10.L</td>
<td width="85">3.9.L</td>
</tr>
<tr>
<td width="87">0x20</td>
<td width="71">32164</td>
<td width="73">32378</td>
<td width="72">33102</td>
<td width="93">32990</td>
<td width="76">32427</td>
<td width="98">32261</td>
<td width="85">33433</td>
<td width="85">33433</td>
</tr>
<tr>
<td width="87">0x18</td>
<td width="71">32271</td>
<td width="73">32481</td>
<td width="72">32997</td>
<td width="93">32890</td>
<td width="76">32529</td>
<td width="98">32369</td>
<td width="85">33334</td>
<td width="85">33349</td>
</tr>
<tr>
<td width="87">0x10</td>
<td width="71">32389</td>
<td width="73">32589</td>
<td width="72">32898</td>
<td width="93">32788</td>
<td width="76">32648</td>
<td width="98">32449</td>
<td width="85">33225</td>
<td width="85">33260</td>
</tr>
<tr>
<td width="87">0xd</td>
<td width="71">32420</td>
<td width="73">32596</td>
<td width="72">32858</td>
<td width="93">32755</td>
<td width="76">------ ?</td>
<td width="98">----- ?</td>
<td width="85">----- ?</td>
<td width="85">----- ?</td>
</tr>
</tbody>
</table>
<p> With threshold at 0xd, threshold position was very hard to determine for nnaida6+8, assume discirminator is running in the noise. Will ignore data for 0xd.</p>
<p> Assuming central position of 32768 and energy per channel of 0.7 keV, below table gives approximate position of threshold in keV.</p>
<table width="789" cellspacing="1" cellpadding="1" border="1" height="155">
<tbody>
<tr>
<td width="740" valign="middle" align="center" colspan="9">Position of threshold (ch)</td>
</tr>
<tr>
<td width="87"> </td>
<td width="144" align="center" colspan="2">nnaida1</td>
<td width="165" align="center" colspan="2">nnaida3</td>
<td width="174" align="center" colspan="2">nnaida6</td>
<td width="170" align="center" colspan="2">nnaida8</td>
</tr>
<tr>
<td width="87">Slow comp threshold</td>
<td width="71">1.9.L</td>
<td width="73">2.10.L</td>
<td width="72">1.9.L</td>
<td width="93">2.9.L</td>
<td width="76">2.10.L</td>
<td width="98">3.11.L</td>
<td width="85">2.10.L</td>
<td width="85">3.9.L</td>
</tr>
<tr>
<td width="87">0x20</td>
<td width="71">423</td>
<td width="73">273</td>
<td width="72">234</td>
<td width="93">155</td>
<td width="76">239</td>
<td width="98">355</td>
<td width="85">467</td>
<td width="85">467</td>
</tr>
<tr>
<td width="87">0x18</td>
<td width="71">348</td>
<td width="73">201</td>
<td width="72">160</td>
<td width="93">85</td>
<td width="76">167</td>
<td width="98">279</td>
<td width="85">396</td>
<td width="85">407</td>
</tr>
<tr>
<td width="87">0x10</td>
<td width="71">265</td>
<td width="73">125</td>
<td width="72">91</td>
<td width="93">14</td>
<td width="76">84</td>
<td width="98">223</td>
<td width="85">320</td>
<td width="85">344</td>
</tr>
</tbody>
</table>
<p> Thus (very roughly), between 0x10 and 0x20, the above table shows the threshold moving by about 10 keV per increment in the threshold.</p>
<p> With the threshold at 0x10, the data rate show on the TapeServer window was ~3Mb/s (uncompressed?).</p>
<p> This was with 1 detector (BB18 2977-20) connected to 4 FEE64s with above settings, a 25Hz pulser and 241Am+207Bi sources (activities in ELog entry 40).</p>
<p> The Good Events rate averaged around 30,000-60,000/s per FEE64 card, with only a few Pause/Resumes coming through.</p>
<p> Example stats screen and hit patterns included below for final configuration.</p> |