High Energy - Engineering Working Group IceCube PY8 Spring Collaboration Meeting Apr 29, 2009 Jim Baccus

HE86

HE110

Closeup of HE110

IceCube Spring Collaboration Meeting High Energy Working Group April 29, Overview and Topics Group of the following people has been meeting once / wk to prepare engineering baseline information for a High Energy design proposal: –Bob Paulos, Jim Haugen, Perry Sandstrom, Andy Laundrie, Tom Hutchings, Tom Ham, Tim Murray, Paul Wisniewski, and Mark Krasberg Two phases of High Energy –HE86: Nine strings in SW corner IceCube, installed in / 2011 season. –HE110: Additional 24 (?) strings north of IceCube installed in 2011 / 2012 & 2012 / 2013 seasons.

IceCube Spring Collaboration Meeting High Energy Working Group April 29, HE86 Assuming HE86 is approved, the following tasks need to be completed in order to make this happen: –Successful testing of DOM / DOR communications extended length (to 3850 m) –Surface Cable extension cable order, mfg, and delivery to the pole –Minor changes to drill (discussed in later slides) –Verification of longer drill reach capabilities Surface Cable Extensions: –These orders would look exactly like Surface Cable orders to Ericsson.  Approximately 7 cables  Lengths 200 m – 600 m

IceCube Spring Collaboration Meeting High Energy Working Group April 29, HE 110 – Counting House Topics discussed –Counting Houses:  One counting house between two rings is best design option  Power / comms likely from Building #61 (next to MAPO) One possible layout shown here…  12 ft x 24 ft  Serves both HE rings  24 hubs for InIce (3 racks)  3 hubs, 7 pwr supplies, IceTop RS485 module (1 rack)  4 patch panel racks  Transformer & air handling equipment

IceCube Spring Collaboration Meeting High Energy Working Group April 29, HE 110 – Strings, DOMs, Locations –String configuration:  # of strings = 24 – 32  # of DOMs / string = 32 – 48  Final numbers will be determined by physics vs. cost tradeoff –DOM design:  High QE PMTs, all else same –Cable design:  No DOMs in dust layer  Reduce # of quads if possible –Hole location:  Keep holes off runway & away from old station

IceCube Spring Collaboration Meeting High Energy Working Group April 29, HE 110 – Potential Cable Orders Surface to DOM Cables –24 – 32 Surface to DOM Cables –Exactly the same as previous Surface to DOM Cables Surface Cables –Design not finalized…  Probably 24 – 32 Surface Cables  Chance that Surface Cables would not be used and we would go to clock & power cables. This is the DOM Hub at the hole configuration.

IceCube Spring Collaboration Meeting High Energy Working Group April 29, Communications Test Plan The greatest risk to be mitigated is communications with DOMs over longer cable lengths (up to 3850m). Here is the current proposed test plan: –Test limits:  Still in the process of refining these  TCal RMS jitter < 5 ns  Successful moat at greatest lengths –Chamberlin Hall system tests:  Various lengths –SPTS PSL) tests:  800m m, 1600m m –South Pole:  Test over Surface Cables with loopbacks on unused special device quads  Lengths TBD

EHWD Reach 4/27 TLB

EHWD Reach FactorsPossible Solutions 1200’ (366m) Adopted standardNone 1500’ (457m) Realistic limit Need extension power cables Have most material at Pole 2400’ (732m) High risk limit of current system, moderate technical challenge to reduce risk Voltage drop (power) Voltage drop (E-stop) Need more hose Return H2O pump marginal Standalone TOS generator Step-Up/Down transformers E-stop remote base station Wireless network Boost pump for return H2O? 2400’ (732m) + Not possible with current system, moderate to major technical challenges to overcome Voltage drops Need more hose Reduced supply flow (slower drilling) Return H2O pump undersized Standalone TOS generator E-stop remote base station or alt cable Wireless network Boost pump for return H2O Fork out $$$ for extra fuel

With a target reach in mind, what tests can be done in 09/10 to validate system capabilities? Test e-stop reach – hook 2 x 1500’ cables in series Build and add extension TOS power cable Test Crrel generator for TOS standalone power (and backup solution – white Gen?) Simulate longer reaches on return H2O line to test limits of pump – install pressure gauge at RWHR for feedback and throttle line Test effect of lower supply flow/temp on nozzle selection and drill speed Some of these activities require engineering and procurement ASAP