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, , , , , The Daya Bay Reactor Neutrino Experiment Liangjian Wen On behalf of the Daya Bay Collaboration Institute of High Energy Physics Daya Bay Detectors Known: Unknown : LA: 40 ton Baseline: 500m Overburden: 112m Muon rate: 0.73Hz/m 2 Far: 80 ton 1600m to LA, 1900m to DYB Overburden: 350m Muon rate: 0.04Hz/m 2 DYB: 40 ton Baseline: 360m Overburden: 98m Muon rate: 1.2Hz/m 2 calibration system PMT Inner acrylic vessel (3m φxH) Stainless steel vessel Bottom reflector Top reflector 5m Mineral Oil LS Gd-LS Outer acrylic vessel (4m φxH) 5m Daya Bay experiment will use 200 ton 0.1% Gd-doped LS and 200 ton normal LS Gd-TMHA + LAB + 3g/L PPO + 15mg/L bis-MSB To ensure IDENTICAL detectors, all Gd-LS will be produced in multiple 4-ton batches and mixed in reservoir on-site. March 2009, a batch of 4 ton Gd-LS was produced successfully. LS production has been started in Oct. 2010 0.1% Gd-LS fluor-LAB Gd-LAB LS hall move SSV SSV sits in pit clean SSV inside insert bottom reflector insert outer AV insert Inner AV close outer AV lid test Gd-LS filling probe lift PMT ladder install top reflector close SSV lid install ACUs Waterproof 8” PMTs: Potting and production finished. Water filtration and circulation system ready for installation. Have begun installing Tyvek and PMTs. Production and testing for all 1600 RPC s have been completed. More than 85% of RPC modules (2 RPCs x 4 layers) have been assembled and most of them tested. Modules for DYB hall will be ready soon. Support structure for DYB hall has been installed and tested. Gas system RPC module 2 n e a r + f a r ( 3 y e a r s ) arXiv:0907.1896: actual arXiv:0907.1896: actual dates differ dates differ ● Shenzhen 55km Hong Kong Goal: Sin 2 2 θ 13 < 0.01 @ 90% CL in 3 years Redundancy is a unique feature for this experiment: Identical antineutrino detector modules to reduce errors and cross check. Multiple muon veto: Two zones of Cerenkov detector + RPC at the top. Total efficiency > (99.5 0.25) %. Daya Bay Layout Daya Bay Sensitivity Liquid Scintillator 5x40ton Gd-LS storage tank 2x200 ton storage pool Mixing N2 room Fillin g QC room LS hall layout Target mass measurement Detectors Assembly October 2010, first AD pair complete, Dry-Run tests finished October 2010, Daya Bay Near Hall Occupancy Daya Bay Hall: data taking, Fall 2011 Ling Ao and Far Halls: data taking, Fall 2012 Tentative Schedule 2012 … … Reach the goal ! Water Cerenkov Detector Progress RPC Detector Progress Daya Bay Experiment Is Hunting for θ 13 Neutrino mixing: where , 1 0 0 0 0 0 0 cos sin 0 sin cos 0 0 0 1 cos 0 sin 0 1 0 sin 0 cos 1 0 0 0 cos sin 0 sin cos 2 1 23 23 23 23 13 13 13 13 12 12 12 12 i i i i PMNS e e e e U | | 2 32 m 32 2 2 sin 21 2 2 sin 2 21 m ? ) 0 ( 2 32 m 13 2 2 sin CP Value of θ 13 is critical for studying CP violation and neutrino mass hierarchy. If Sin 2 2 θ 13 <0.01, long baseline experiments with conventional beam have little chance to determine CP violation. Determining θ 13 by observing electron antineutrino disappearance at reactor. Clean signal, only related to θ 13 . Relative measurement with near and far detectors. Near Far he 11 th International Workshop on Next generation Nucleon Decay and Neutrino Detectors Toyama, Japan December 13 –16, Light from LEDs can be observed as well as Cherenkov light caused by cosmic ray muons passing acrylic. calibration LED PMT Charge (PE) with LED flashing LED Flashing Dry Run of the first AD pair Muon Off-axis LED e ~ Consistent performance of AD pair LED ACU A full end-to-end test of the fully instrumented Antineutrino Detectors prior to filling them with liquid scintillator. Double pulse LED to mimic even mass PMNS f v U v T e f v v v v } , , { T mass v v v v } , , { 3 2 1
description
install top reflector. clean SSV inside. test Gd-LS filling probe. insert outer AV. The Daya Bay Reactor Neutrino Experiment. Top reflector. calibration system. calibration LED. PMT. Inner acrylic vessel (3m φ xH). - PowerPoint PPT Presentation
Transcript of , ,
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The Daya Bay Reactor Neutrino ExperimentLiangjian Wen On behalf of the Daya Bay Collaboration Institute of High Energy Physics
Daya Bay Detectors
Known:
Unknown:
LA: 40 tonBaseline: 500mOverburden: 112mMuon rate: 0.73Hz/m2
Far: 80 ton1600m to LA, 1900m to DYBOverburden: 350mMuon rate: 0.04Hz/m2
DYB: 40 tonBaseline: 360mOverburden: 98mMuon rate: 1.2Hz/m2
calibration systemPMT
Inner acrylic vessel (3m φxH)
Stainless steel vessel
Bottom reflector
Top reflector
5m
Mineral OilLS
Gd-LS
Outer acrylic vessel (4m φxH)
5m
Daya Bay experiment will use 200 ton 0.1% Gd-doped LS and 200 ton normal LSGd-TMHA + LAB + 3g/L PPO + 15mg/L bis-MSB
To ensure IDENTICAL detectors, all Gd-LS will be produced in multiple 4-ton batches and mixed in reservoir on-site.March 2009, a batch of 4 ton Gd-LS was produced successfully.
LS production has been started in Oct. 2010
0.1% Gd-LS fluor-LAB Gd-LAB
LS hall
move SSV SSV sits in pit clean SSV inside insert bottom reflector
insert outer AV
insert Inner AV
close outer AV lid test Gd-LS filling probe
lift PMT ladder
install top reflector close SSV lid install ACUs
Waterproof 8” PMTs: Potting and production finished.Water filtration and circulation system ready for installation.Have begun installing Tyvek and PMTs.
Production and testing for all 1600 RPC s have been completed.More than 85% of RPC modules (2 RPCs x 4 layers) have been assembled and most of them tested.Modules for DYB hall will be ready soon.Support structure for DYB hall has been installed and tested.
Gas system
RPC module
2 n
ear +
far (3
years)
arXiv:0907.1896: actual dates differarXiv:0907.1896: actual dates differ
●
Shenzhen
55km
Hong Kong
Goal: Sin22 θ13 < 0.01 @ 90% CL in 3 years
Redundancy is a unique feature for this experiment:
Identical antineutrino detector modules to reduce errors and cross check.
Multiple muon veto:Two zones of Cerenkov detector + RPC at the top.Total efficiency > (99.5 0.25) %.
Daya Bay Layout Daya Bay Sensitivity
Liquid Scintillator
5x40ton Gd-LS storage tank
2x200 ton storage pool
Mixing
N2 roomFilling
QC room
LS hall layoutTarget mass measurement
Detectors Assembly
October 2010, first AD pair complete, Dry-Run tests finishedOctober 2010, Daya Bay Near Hall Occupancy
Daya Bay Hall: data taking, Fall 2011Ling Ao and Far Halls: data taking, Fall 2012
Tentative Schedule
2012 … … Reach the goal !
Water Cerenkov Detector Progress RPC Detector Progress
Daya Bay Experiment Is Hunting for θ13
Neutrino mixing: where ,
100
00
00
cossin0
sincos0
001
cos0sin
010
sin0cos
100
0cossin
0sincos2
1
2323
2323
1313
1313
1212
1212
i
i
i
i
PMNS e
e
e
e
U
|| 232m 32
2 2sin 212 2sin 2
21m
?)0( 232 m
132 2sin CP
Value of θ13 is critical for studying CP violation and neutrino mass hierarchy.If Sin22 θ13 <0.01, long baseline experiments with conventional beam have little chance to determine CP violation. Determining θ13 by observingelectron antineutrino disappearance at reactor.Clean signal, only related to θ13.Relative measurement with near and far detectors.
NearFar
The 11th International Workshop on Next generation Nucleon Decay and Neutrino Detectors Toyama, Japan December 13 –16, 2010
Light from LEDs can be observed as well as Cherenkov light caused by cosmic ray muons passing acrylic.
calibration LED
PMT Charge (PE) with LED flashing
LED Flashing
Dry Run of the first AD pair
MuonOff-axis LED
e~
Consistent performance of AD pair
LED
ACU
A full end-to-end test of the fully instrumented Antineutrino Detectors prior to filling them with liquid scintillator.
Double pulse LED to mimic events
massPMNSf vUv Tef vvvv },,{ T
mass vvvv },,{ 321
