<p>The main experiment changed to a carbon reaction target at F8 (similar thickness of CH2 previously used), and retuned the ZDS. First BigRIPS run after retuning is 40Mg_1093 (at 2:29 am, Nov 30th)</p>
<p>The background at F11 has increased. The neutron backgroun incresead by a factor of ~10. The rates of visual scalers also increased; for example Si Top/Bottom from about 50 Hz to 300 Hz (see attachment 1).</p>
<p>One possible explanation are higher light particle rate at F11. By comparing the PID for C target (attachment 2) with that of CH2 target setting (e.g. https://elog.ph.ed.ac.uk/AIDA/492), it looks like the new conditions have a higher transmission for A/Q=3 fragments (3H et al). Also, in the new setting the Si isotopes are also transmitted to F11.</p>
<p>The implantation depth is still good; same as we had for C target at F8 (compare 40Al distribution in attachment 3 with what we had before).</p> |