Installing dayabay software

I record here my experiences installing the Daya Bay software locally at Siena. These notes may prove useful to someone else (or myself at a later date: I feel like I've done this all before and lost the info!)

It took a bit of poking around to find what I thought was the correct instructions. Trying to navigate through the wiki from the top level didn't get me very far... all the promisingly named links seemed to point to self proclaimed outdated pages, but no links to the current pages were included.

I finally gave up on trying to navigate the links from the top level and tried searching within the wiki. This also didn't get me anywhere. In fairness, after I found the correct link through other means, revisiting this search, it did sortof find the correct link in one of pages it found (far down the list) about validation software.

The easiest way to get to the correct page was simply doing a google web search for "install dayabay software." The first unsponsored link took me to the correct page.

Submersion tests of potted MACRO tubes

Two potted MACRO photomultiplier tubes, sn 6411 and 7423, were submerged and pressurized to 29.5 psig. After approximately 2 days the pressure was reduced to 0 psig and brought back up (total cycle time ~10 min.) After two more days the pressure was cycled again. The pressure was then maintained at 29.5 for 6 more days until tube 7423 failed, tripping the HV supply. Interestingly this tube (7423) began to work again the next day, although with quite a bit of intermittent noise not seen before the failure. 7423 failed for good at some point in the next few days, and did not recover. When disconnected from HV we discovered water in the HV cable. At this point we depressurized the vessel and opened it up to investigate.

PMT sn 6411 seemed to perform normally during the entire test.

Photos

The photos above (click for a better look) show the feedthrough region of the tube that failed, sn 7423. Although it looks like water may have made it past the first two ribs of the feedthrough seal, it is difficult to say if water made it past the third sealing rib. There is no indication of water anywhere else in the base, other than it coming out the end of the HV cable.

Surprisingly, the tube that did not fail (sn 6411) has visible water in it. These photos show standing water between the glass and the plastic shell. The blue inside is the B20 cap on the pin end of the PMT.