1. Eun-Ju Jeon Sejong Univ. Sept. 09, 2010 Status of RENO Experiment Neutrino Oscillation Workshop (NOW 2010) September 4-11, 2010, Otranto, Lecce, Italy

2. Outline  Overview of the RENO Experiment - YongGwang Power Plant - Experimental Setup - Statistical & Systematic Uncertainties - Expected  13 Sensitivity - Schedule  Construction Status of the RENO Experiment - Tunnel - Detector - DAQ & Data Analysis Tools

3. RENO Collaboration (13 institutions and 40 physicists)  Chonnam National University  Chonbuk National University  Dongshin University  Gyeongsang National University  Kyungpook National University  Pusan National University  Sejong University  Seokang Information University  Seokyeong University  Seoul National University  Sungkyunkwan University  Institute of Nuclear Research RAS (Russia)  Institute of Physical Chemistry and Electrochemistry RAS (Russia) +++ http://neutrino.snu.ac.kr/RENO

4.  Located in the west coast of southern part of Korea  ~250 km from Seoul  6 reactors are lined up in roughly equal distances and span ~1.3 km  Total average thermal output ~16.4GW th (2 nd largest in the world) YongGwang Nuclear Power Plant YongGwang( 靈光 ): = glorious[splendid] light

5. RENO Experimental Setup

6. Google Satellite View of Experimental Site

7. 100m300m 70m high 200m high 1,380m290m Far Detector Near Detector Reactors Schematic View of Underground Facility

8. RENO Detector  354 10” Inner PMTs : 14% surface coverage  67 10” Outer PMTs

9. 2.73 GW per reactor ⅹ 6 reactors 1.21x10 30 free protons per targets (16 tons) Near : 1,280/day, 468,000/year Far : 114/day, 41,600/year 3 years of data taking with 70% efficiency Near : 9.83x10 5 ≈ 10 6 (0.1% error) Far : 8.74x10 4 ≈ 10 5 (0.3% error) Expected Number of Neutrino Events at RENO

10. Systematic SourceCHOOZ (%)RENO (%) Reactor related absolute normalization Reactor antineutrino flux and cross section 1.9< 0.1 Reactor power0.70.2 Energy released per fission0.6< 0.1 Number of protons in target H/C ratio0.80.2 Target mass0.3< 0.1 Detector Efficiency Positron energy0.80.1 Positron geode distance0.10.0 Neutron capture (H/Gd ratio)1.0< 0.1 Capture energy containment0.40.1 Neutron geode distance0.10.0 Neutron delay0.40.1 Positron-neutron distance0.30.0 Neutron multiplicity0.50.05 combined2.7< 0.5 Expected Systematic Uncertainty

11. RENO Expected Sensivity 90% CL Limits Discovery Potential” (3  ) 10 times better sensitivity than the current limit

12. Schedule Excavation & Underground Facility Construction Detector Commissioning Detector Construction Geological Survey & Tunnel Design Activities Detector Design & Specification 2006200720082009 369 12 369 369 3 69 2010 369 12 Activities  Tunnel facility, detector structure & buffer steel tanks completed  June 2010 : Acrylic containers installed  Aug. 2010 : PMT test completed  Sep. 2010 : Installation of PMTs, veto tyvek and liquid handling system  Oct. 2010 : Installation of DAQ & HV and filling with liquid scintillator  Nov. 2010 : Closing and detector commissioning  Dec. 2010 : Start data taking

13. Comparison of Reactor Neutrino Experiments ExperimentsLocation Thermal Power (GW) Distances Near/Far (m) Depth Near/Far (mwe) Target Mass (tons) Cost (US $) # of people Double-CHOOZFrance8.7410/1050115/30010/10?> 160 RENOKorea17.3290/1380120/45016/16~10M40 Daya BayChina11.6360(500)/1985(1613)260/910 40  2/80 ?> 230

14. Summary of Construction Status 03~11, 2007 : Geological survey and tunnel design are completed. 06~12, 2008 : Construction of both near and far tunnels are completed. 12, 2008 ~ 06, 2009 : Veto tanks and peripheral facilities (electricity, air circulation, drainage, network, etc.) are completed. 11, 2008 : SK new electronics were adopted and ready. 06~11, 2009 : Buffer steel tanks are installed 06, 2010: Acrylic containers are installed. 08, 2010: PMT test is completed PMT installation is underway. Both near and far detectors are expected to be ready for data-taking in late 2010.

15. Tunnel Construction (2008.6~2008.12) by Daewoo Eng. Co. Korea

16. Near & far tunnels are completed by Daewoo Eng. Co. Korea (2008.6~2009.3) Near site Far site

17. by NIVAK Co. Korea Vertical detector halls & steel structure are ready (2008. 12~2009. 06)

18. Experimental Hall

19. by NIVAK Co. Korea Buffer steel tanks are installed (2009.6~2009.11)

20. Installation of Acrylic Vessels (2010. 6)

21. PMT Holder (2009. 10~12) and Mounting (2010. 9)

24. Summary  RENO is suitable for measuring  13 (sin 2 (2  13 ) > 0.02)  RENO is near completion.  Data –taking is expected to start in late 2010. Thank you!

25. Backup

26. New Reactor Neutrino  13 Experiment  Lower background - Improved detector design - Increased overburden  CHOOZ : R osc = 1.01 ± 2.8% (stat) ± 2.7% (syst)  Larger statistics - More powerful reactors (multi-core) - Larger detection volume - Longer exposure  Smaller experimental errors - Identical multi detectors → Obtain ~1% precision !!!

27. νeνe νeνe νeνe νeνe νeνe νeνe Distance Probabilité ν e 1.0 1200 to 1800 meters Obseved flux before oscillation Oscillations observed as a deficit of anti-neutrinos sin 2 2θ 13 Experimental Method of  13 Measurement  Find disappearance of e fluxes due to neutrino oscillation as a function of energy using multiple, identical detectors to reduce the systematic errors in 1% level.

28. Detection of Reactor Neutrinos data from CHOOZ hep-ex/0301017v1 (1) 0.7<E prompot <9MeV (2) 5<E delayed <11MeV (3) 1μs<ΔT <200μs e + energy n capture energy

29. Near detector site: - tunnel length : 110m - overburden height : 46.1m Far detector site: - tunnel length : 272m - overburden height : 168.1m (2007.3~2007.8) Rock Quality Map

30. Design of Tunnels Experimental hall Wing tunnel(L) Wing tunnel(R) Detector Wing tunnel(R) Access tunnel Detector vertical hall (2007.9~2007.11) Design of Tunnel