Weather conditions remained good at Pole this week as we approached the holiday weekend. The temperature hovered around -40 degrees, with a slight warming trend during the week. There were a couple of flight delays due to weather in McMurdo, but on the whole the flights have been coming in regularly at the rate of about four per day. The IceCube population is up to 51. Because of the holiday, this is a 5-day work week. Drilling is down to a skeleton crew for Saturday and Sunday.
This week is Safety week and we confirmed the plan and the date for next week's Multiple Casualty Exercise. This exercise will test the RPSC rescue teams' ability to handle simultaneous emergencies at different locations on the ice. IceCube will also test its procedures for evacuation and muster. The scope of this drill will also expand to IceCube in Madison and to the NSF. We plan to review and revise the Incident Reporting Process for the communication path between UW and the NSF in the event of an actual emergency. The RPSC rescue teams have completed their Safety Tours through the Drill Camp and the ICL. They toured this past week in order to get a handle on the logistics/layout of each site. Further, they reviewed the safety equipment on site. The tours went well. The RPSC rescue teams were very appreciative of the effort. Our weekly safety meetings have begun at the Drill Camp. With each shift, we potential sources of injury and other hazards. Individuals have the opportunity too raise their own safety issues or questions. All IceCube fire extinguishers at the Drill Camp, ICL (IceCube Lab), and in the OML (Optical Module Lab) have been weighed and inspected for the season. Three extinguishers found to be low in charge have been replaced. All CO/Fire detectors have been installed and tested, with new batteries being inserted at the Drill Camp, ICL and at the OML.
Of the approximately 207,000 lbs of IceCube repair or upgrade cargo scheduled for delivery to Pole week ending November 24 we had about 177,000 lbs. delivered. We now have all of the 14 Surface Cables and the first four Surface to DOM Cables are on site along with four spools of Drill Supply Hose. Drill equipment that is urgently needed has been identified and "Hot Listed" for delivery to Pole. Delivery of DAQ (Data Acquisition) components has been delayed until the snow ramp is constructed at the ICL to facilitate delivery to the first deck. All IceTop tanks and refurbish or repair equipment has been delivered. DOMs are arriving within scheduled timeframes.
The drill setup is continuing to progress as the drill team inspects the pumps and hoses that may have suffered damage over the winter. Repairs have been made or are underway. All the frozen hoses have been thawed and are back in circuit. The firn drill has been inspected, and despite extensive damage, we are in the process of repairing it and hope to have it operational again by either Monday or Tuesday of next week. The major activities remaining at the moment before we can complete the SES setup and begin debugging are to install the water tank filters and the remaining heater Y-strainers. We have just received the remaining water tank filter screens which will allow us to complete setup of those tanks and the remaining pumps. We hope to receive the Y-strainers on Monday which will allow us to complete the setup in MHP 1 and 3 and then commence water flow and testing of the entire SES.
The Tower site setup is also nearing completion. We have the main hose in place, covered and heated. The TOS (Tower Operation System) and Tower have been positioned and setup is proceeding on those buildings. The main cable reel and return water hose reels are in place and the anchor locations marked out. We still need to add a section of hose to the hose reel, but are waiting for the temperature to increase a little more before doing so. While the target date of drilling on Dec 1 still looks like a possibility, we are still hopeful of a start date somewhere near the scheduled date.
After starting on schedule, we continued to test DOMs (Digital Optical Modules) with relatively few problems. Due to shipping delays we started building a buffer, and have 1 string of DOMs in reserve now. Pallets began to arrive and we have tested DOMs for strings 63 and 64. The second cycle of IceTop DOMs is being tested now These DOMs will be retested later in the season. We have constructed a tent to shelter the DOMs from direct sunlight, and attached the breakout boxes to the structure for ease of connection. We've dubbed this the 'DOM milking barn'.
Cable inventory of the ICL is completed, all of the SJBs (Surface Junction Boxes) are on site and cable/ICL shipments are coming in. The first floor of the ICL has been cleared and reorganized to serve as a useful working place during the season and for DNF (do Not Freeze) storage and use by the winterovers later. Some posters are already on display, and more are expected. We plan to use this space to brief the Distinguished Visitor tour on November 28 before taking them upstairs to see the event display and their trip to the drill camp. An attractive and effective on-line event display is set to play back in near real time events in which more than 10 per cent of the DOMs in IceCube-22 are hit. This display will be the focal point of the briefing for DVs and other visitors to IceCube.
During the past week ten more DOMs were mounted for a total of 20. Five pairs of tanks were set in trenches and we installed 20 DOMs in the ten tanks The 10 FCUs (Freeze Control Units) sent from Delaware have passed their calibration check and are ready to install. Two of the 2006 units have passed the calibration check and are ready to install. The checkout of the remaining units will proceed on schedule.
A humidifier has been installed for testing in the science building to bring the humidity of the air passing through the data taping system to within specification of the tape drives. Concerns have been raised that the extra moisture would cause ice build up on the inside of the windows of the optical experiments locate in B2. No increase near the optical experiments above the baseline of about 4%RH was observed. A water line will be run to the humidifier for continuous operation. Assuming continuous operation also does not affect the optical experiments, the taping system will be moved to the science building. Maintenance work on a core server continued, in conjunction with upgrades of work stations. The bulk of IT cargo is expected this coming week, which includes new DOM Hubs, and supporting equipment such as UPSs (Uninterruptible Power Supplies).
The first phase of on-ice AMANDA work ends November 26. The intention is to leave AMANDA TWR running in 2007 mode. Extensive repair and upgrading took place in a short time. The whole AMANDA group would like to thank everybody for the support during our four week stay. This season was really successful, and we have now a detector, that is as stable, as never before! Thanks a lot for setting up new computers, taking care of the hardware, searching and transporting packages, to the Winterover crew, to all IceCubers and to the great station people!
