South Pole Weekly Report, February 08, 2009

The current IceCube population stands at 13 and this is the final Construction Report for the 2008-09 on-ice season. All IceCube personnel (except our two winterovers of course) are scheduled to leave on/before Friday, Feb 13th.

Two of the three main generators require rear seal replacements. This week one was completed by RPSC mechanics and relocated to the SES. The 3rd and final generator is to be completed and delivered to the SES next week.

No strings were deployed this week. This week there were no reportable injuries and no new incident reports. This marks 99 days on-ice without injury/incident.

The IceTop tanks were closed by Monday and we removed the FCUs of another 9 stations and tied their power and communication cables to the survey poles. We did one FCU removal using the snowmobiles to train the winterovers since they need to remove the FCUs from tanks that will not be frozen by the end of next week. There are still 6 stations left with their FCUs connected but we hope to remove another 4 of them within the next week. All the other stations are completely ready for the winter. We repaired all the sun-shades and prepared the WeatherPort for the winter. The rest of the week we helped with the commissioning of the IceTop DOMs. The low-level commissioning has been completed and we are currently working on the integration of the IceTop DOMs into the data acquisition system. We also took about 9 hours of test data to calibrate the IceTop thresholds.

The End-of-Summer IceCube "Night Shift" takes a break from detector commissioning activities in B2 and the ICL for a group photo at the Geographic Pole.

Photo by J. Jacobsen

The last of the Promise RAID arrays was upgraded on Tuesday without a snag. Thanks to everyone who helped coordinate downtime on critical systems and made it seem easy. Two workstations, one in B2 and one in the ICL, now intelligently switch between using the standard satellites when they are available and the Iridium OpenPort array when they are not. Hopefully this will be useful to the winterovers in case of emergency. Temperatures in the ICL stabilized at a good temperature with the help of two facilities engineers who will winter at the pole. We met with them and a few other facilities representatives to discuss cooling plans for the immediate and distant future. While cooling all the servers we squeeze into the ICL will remain a challenge, plans seem headed in the right direction. Goals for the upcoming week include helping tune Zenoss alerts so that they're not overwhelming the winterovers, connecting a few remaining keyboard, video, and remote management interfaces, documenting changes made in the last few weeks, and heading home to get out of the winterovers' way.

Four new strings were commissioned this week and integrated into pDAQ on Feb. 1, with a successful four-hour IC53 run quickly followed by the usual verification activities. As a bonus, a half-hour run with soft local coincidence (SLC) was also run on IC53. The SLC data is still being looked at; if it proves OK, this represents a big milestone and accomplishment for the DAQ.

Betelnut continues to be used for IC40 and integration runs. The DAQ group diagnosed and fixed a problem with the calibration trigger; the fix was checked by the Verification team. Verification runs are now being taken with an updated version of pDAQ (Boulevard_RC1). IceTop minbias hit calibration runs were taken with pDAQ this week. The method was trouble-free and looks very promising as a default run mode for IC53. IceTop threshold calibration runs were carried out on February 6 and were mostly successful; the lowest thresholds generated a total event rate of roughly 4kHz, which is currently too much for pDAQ. A workaround is planned for February 7, but eventually improvements to the Event Builder will likely be required to handle such a high rate. The first IceCube Live operator documentation was circulated to the winterovers on February 6, with a training session planned for the evening of February 7. The training session will include contingency strategies for dealing with hardware failures and similar problems. The temperature in the ICL spiked briefly on February 6. In order to make information about ICL temperatures more widely available, IceCube Live now has an 'environment' page which reports current and recent temperatures and air flow speed measured at various points in the ICL. Email alerts or pages to the winterovers are possible but are not yet activated, pending decision about what our higher-level operational strategy should be to handle temperature fluctuations in the ICL.

Commissioning for IceTop DOM has been done. No unexpected issues were found. Three DOMs have higher rates. These DOMs are former in-ice DOMs which have been known to be noisy. We still have to add IceTop DOMs into the offline database and create config files for pDAQ. Commissioning of the 6 remaining strings (17-26-27-28-37-83) has begun. Commissioning of strings 2 - 3 - 4 will be redone because we added the QUADs which were unplugged last week.

On February 3 the AMANDA data acquisition system was shut down after backing up all data. We completed the disassembly of the AMANDA hardware in MAPO, still useful equipment was packed and is on its way back to Mainz. Other equipment was sent to surplus.

It's a busy little airport as summer personal are moved out and station fuel is topped off.