1. Mark Vagins Kavli IPMU, University of Tokyo 2 nd Open Meeting for the Hyper-Kamiokande Project Kashiwa January 14, 2013 Gadolinium for Hyper-K

2. The GADZOOKS! idea is now ten years old. R&D has been under way almost that long. Here’s the UCI setup: 2010 2005 2007 2008

3. After various studies at UCI, Kamioka, KEK, OkayamaU, LSU, UCD, and LLNL, finally a dedicated Gd test facility was built in the Kamioka mine, complete with its own water filtration system, 50-cm PMT’s, and DAQ electronics. This 200 ton-scale R&D project is called EGADS – Evaluating Gadolinium’s Action on Detector Systems. Super-K Water system ５０ｍ EGADS Hall (2500 m^ 3) Super-Kamiokande

4. 200 ton (6.5 m X 6.5 m) water tank (SUS304) 240 50-cm PMT’s Selective Water+Gd Filtration System Transparency Measurement (UDEAL) EGADS Facility In June of 2009 we received full funding (~$4,300,000) for this effort. Gd Pretreatment System

5. Layout of EGADS hall (Hall E) 15m 10m 200-ton test tank 15 m 3 tank Pre-treat UDEAL Pre-treatment system Main water circulation system Resin Gd removal system Membrane flushing system 1.4 m 3 tank Significantly rebuilt/upgraded since last meeting

6. 12/2009 6/2010 2/2010 12/2010 Hall E and EGADS

7. ;. 11/2011 Selective Water+Gd Filtration System 15-ton Gadolinium Pre-treatment Mixing Tank Now, after a decade of extremely promising studies on three continents, EGADS will provide the conclusive final test of GADZOOKS! in FY2013. Main 200-ton Water Tank (232 50-cm PMT’s + 8 HK test tubes to be installed this spring)

8. ;. Hall E We had been using the smaller 15-ton pre-treatment tank for reduced-time Gd filtration studies. After achieving good transparency control of Gd-loaded water, we felt ready to shift operations to the 200-ton main tank. This happened last month.

9. SK-III and SK-IV Ultrapure Water = 74% - 82% We understand the Gd water system’s behavior and can use it to control the transparency of dissolved gadolinium. Efforts to further improve transparency continue, but we are now confident that light loss due to Gd will ultimately be acceptable.

10. We can run stably without measurable Gd loss.

11. 15 ton EGADS Test Tank 3X3 EGADS Selective Filtration System Intake Pump (>4 ton/hr) 5  m 1 st Stage Filter Concentrated Gd NF Reject Lines UV #1 Membrane Degas 0.2  m 2 nd Stage Filter 0.5 ton Collection Buffer Tank Repressurization Pump (>0.6 MPa, >4 ton/hr) Repressurization Pump (>0.6 MPa, >3 ton/hr) Nanofilter #2 Nanofilter #1 Ultrafilter #1 Repressur- ization Pump (>0.9 MPa, >2 ton/hr) TOC 5  m Filter 0.5 ton Buffer Tank RO #1 Ultrafilter #1 Ultrafilter #2 Repressurization Pump (>0.9 MPa, >1.5 ton/hr) DI #2 5  m Filter RO #2 RO Permeate Lines Conveying Pump (~0.35 MPa, >4 ton/hr) Recycles RO Reject Lines Chiller UF#1 Reject Line UF#2 Reject UV #2 0.32% 0.33% 0.01% DI #1 To Drain 8 ℓ/min Nov. 20, 2012 99.67% of Gd, 15 ℓ/m Amberjet

12. EGADSEGADS valuating adolinium’s ction on etector ystems We expect all Gd R&D to be completed during FY2013. But what happens in Hall E after that? E G A D S mploying adolinium to utonomously etect upernovas

13. 13 Recently Funded: Multi-messenger Supernova Astronomy X-ray,  - ray, Optical, Infrared, GW, and Neutrino Approved - June 2012 ~$1.6M for EGADS/IPMU This additional money will allow the conversion of EGADS from an R&D facility into the world’s most advanced water-based supernova neutrino detector.

14. Our target: send announcement within one second of the SN neutrino burst’s arrival in EGADS. ~90,000  events @ Betelgeuse ~30  events @ G.C.

15. An EGADS timeline: 2009 2010 2011 2012 2013 2014 2015 2016 2017 R&D Project Approved Hall E Excavation Build 200-ton Tank Install Water Systems 15-/200-t Pure Water Runs 15-ton Tank Gd Runs 200-ton Tank Pure Water Run w/o PMTs 200-ton Tank Gd Run w/o PMTs 200-ton Tank PMT Installation 200-ton Tank Pure Water Data-taking Run 200-ton Tank Gd Data-taking Run ATM  QBEE Electronics Upgrade Full Galaxy Supernova Sensitivity Fully Automated Instant Supernova Alert Capability

16. So, the gadolinium R&D phase is giving way to the era of useful gadolinium-loaded WC detectors. The technology is reaching maturity. Now water companies can prepare realistic, competitive bids for adding gadolinium to the Hyper-Kamiokande water system.

17. EGADS Selective Filtration System Hyper-K Membrane Rack

18. SCW’s 600 m 3 /hr Hyper-K Selective Filtration System UF1 UF2 RO1 RO2 NF1 NF2 Current design = 24 m (L) X 23 m (W) X 4 m (H) Available space = 32 m (L) X 11 m (W) X 12 m (H)  Two-level water room

19. = ~958,000,000 JPY This exact, bid-ready price is for one HK cavern’s gadolinium-related equipment. It is based on SCW’s experience gained from building and operating EGADS. Adding gadolinium-related water system equipment for the full detector (i.e., both caverns) will therefore add about 1,900,000,000 JPY to the total project cost.

20. This very preliminary price is for the entire Hyper-K water system, including the Gd option and radon-free air. It is based on the original EGADS call for bids. Gadolinium-related equipment comprises roughly half of this total. = ~ $59,000,000

21. In conclusion...  After a decade of studies around the world, gadolinium-in-water R&D is entering its final phases.  Expected within the coming year, results from EGADS will likely affect the future of all future large water Cherenkov detectors.  Now that the needed technologies have been developed and tested, multiple water companies feel confident enough to prepare bid-quality designs and pricing for Gd-capable water systems for Hyper-Kamiokande.  Based on this, it adding gadolinium capability to Hyper-K’s water systems will contribute ~2% to the total project costs.  The HK water system working group will work to refine and include this design and pricing information in the official Hyper- K documentation and upcoming proposal-like-objects.