Karsten Heeger, Univ. of Wisconsin UW, June 3, 2010 The DM-Ice Test Detector Detector Concept Mechanical Assembly Vessel Options Logistics Considerations Schedule

Karsten Heeger, Univ. of Wisconsin UW, June 3, 2010 DM-Ice Test Detector stainless or titanium cylinder main electronics boards for 2 PMTs IceCube cable copper plate (2”?) penetrator HV boards backfilled with nitrogen 5” PMT light guides NAIAD detector package HV cable breakout cable mechanical suspension below DOM m Teflon mechanical supports for NAIAD crystals+light guide+PMT assembly IceCube cable breakout Conceptual Overview

Karsten Heeger, Univ. of Wisconsin UW, June 3, 2010 NAIAD Detector Detectors existing detectors (PMTs, light guide, crystal) from previous experiment, will be retrieved from Boulby mine in UK in July will need to replace optical coupling grease will integrate detectors into new housing design for deployment with IceCube strings 79 or 80.

Karsten Heeger, Univ. of Wisconsin UW, June 3, 2010 DM-Ice Test Detector Components 2x 5” PMTs 2x light guides 1 NAIAD crystal 2x mainboards 2x HV boards copper shielding as required 1 or more penetrators + cable 1 suspension system Weight 1 stainless or Ti pressure housing ??? negligible ~100 lbs ~20 lbs ~ lbs for stainless options ~ lbs for Ti options

Karsten Heeger, Univ. of Wisconsin UW, June 3, 2010 DM-Ice Test Detector Suspension –suspended from steel cables below DOM 60 –in addition or instead of weight stack at bottom of string –weight may range from lbs based on design choice Electrical Connections –special device connector at breakout 30 above DOM 59 –8pin + ground –signal to be transmitted into ICL via surface junction box –connect to dor card in ICL

Karsten Heeger, Univ. of Wisconsin UW, June 3, 2010 Test Detectors for Feasibility Study 2 identical detectors, strings 79 and 80

Karsten Heeger, Univ. of Wisconsin UW, June 3, 2010 DM-Ice Test Detector Housing Options Under Consideration Option A “mushroom” Option B “straight cylinder” Option C “cylinder+DOM”

Karsten Heeger, Univ. of Wisconsin UW, June 3, 2010 DM-Ice Test Detector Housing Options Under Consideration Option A “mushroom” Mechanical Suspension –Attach to end of IceCube string below last DOM. –15-20m below end of string –Suspend from end of IceCube cable with stainless cable or chains Electronics and Cabling –One special breakout cable from end of Icecube cable to DM-Ice detector. –Only one penetrator into DM-Ice pressure vessel. –Use IceCube mainboard for waveform capture and HV board –All HV is internal to pressure vessel. Housing –Shield radioactive background of electronics from detectors with copper plate (~2”) –Backfill with nitrogen for humidity and moisture control. –reduce diameter of long cylinder to save weight and material –No neutron detector, just NAIAD crystal

Karsten Heeger, Univ. of Wisconsin UW, June 3, 2010 DM-Ice Test Detector Housing Options Under Consideration same considerations as Option A except straight cylinder for ease of fabrication and simplicity slightly heavier because of material used in pressure housing Option B “straight cylinder”

Karsten Heeger, Univ. of Wisconsin UW, June 3, 2010 DM-Ice Test Detector Housing Options Under Consideration Mechanical Suspension –Attach to end of IceCube string below last DOM. –15-20m below end of string –Suspend from end of IceCube cable with stainless cable or chains Electronics and Cabling –Use DOM sphere to house mainboards –One special breakout cable from end of Icecube cable to DOM –Multiple penetrators in and out of DOM sphere –HV boards could be in DOM sphere (requires HV through penetrator) or in detector cylinder Housing –Backfill with nitrogen for humidity and moisture control. –reduce diameter of detector cylinder to save weight and material –No neutron detector, just NAIAD crystal Option C “cylinder+DOM”

Karsten Heeger, Univ. of Wisconsin UW, June 3, 2010 DM-Ice Test Detector Housing Comparison Option A “mushroom” Option B “straight cylinder” Option C “cylinder+DOM” – compact mechanical design – minimum number of feedthroughs and penetrators – ease of handling, single object – heavier (tot weight lbs) – more feedthroughs and penetrators – multiple objects, handling possibly more complicated – lightest option (370 lbs)

Karsten Heeger, Univ. of Wisconsin UW, June 3, 2010 Logistics of DM-Ice Detector Shipment –by air from Madison by Oct 22, 2010 –special shipping box, expected total weight ~ lbs per detector –constrains on shipping box (pallet size) Storage –on surface, do not worry about cosmic activation for feasibility study –temperature variations from +30 to -40 deg C OK Pre-deployment tests at Pole –unpacking from shipping box and visual inspection of outside –suspend detector from lifting eyes or set up in stand –HV electrical test and readout of detector’s PMT signal in test station Handling at Pole –forklift with boom for positioning –frame or crate with wheels for easy of movement –winch inside tents for pre-deployment tests and for deployment? Anticipated deployment date –Dec 15, 2010

Karsten Heeger, Univ. of Wisconsin UW, June 3, 2010 Special Equipment for DM-Ice Detector Deployment Equipment Needs for Transport and Handling –watertight shipping and storage box –frame with wheels for handling and positioning –boom for forklift? –frame or winch in test tent for detector handling during pre-deployment tests –frame or winch in TOS for detector handling during deployment activities Equipment Needs for Pre-Deployment Tests –power supply –DAQ –computer setup at Pole –can we use existing facilities for predeployment tests? ICL OML

Karsten Heeger, Univ. of Wisconsin UW, June 3, 2010 Logistics of DM-Ice Detector Assumptions in planning transport and handling of detector for feasibility study –ensure mechanical integrity of detector –maximize integration and testing time in Madison to minimize risk of failure –do not worry about cosmogenic activation during air shipment for this feasibility study –allow pre-deployment functionality tests at Pole –minimize storage time on ice (as much as reasonably possible)

Karsten Heeger, Univ. of Wisconsin UW, June 3, 2010 Schedule Overview Overview design decisions by end of June ready for integration in Sep shipment by Oct 22, weeks until shipment

Karsten Heeger, Univ. of Wisconsin UW, June 3, 2010 Schedule Details Design Phase to be completed by end of June design decisions by end of June

Karsten Heeger, Univ. of Wisconsin UW, June 3, 2010 Schedule Details Procurement FabricationPhase July/August ready for integration in Sep

Karsten Heeger, Univ. of Wisconsin UW, June 3, 2010 Schedule Details Integration Phase September/October shipment by Oct 22, 2010