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TEXONO Research Program on Low Energy Neutrino and Astroparticle Physics. Recent Status of Neutrino Physics TEXONO Collaboration : Overview Kuo-Sheng( 國聖 ) Reactor Neutrino Laboratory ※ Facilities ※ Research Topics R&D Program. Henry T. Wong / 王子敬 Academia Sinica / 中央研究院 - PowerPoint PPT Presentation
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TEXONO Research Program on Low Energy Neutrino and Astroparticle Physics
Recent Status of Neutrino Physics
TEXONO Collaboration : Overview
Kuo-Sheng( 國聖 ) Reactor Neutrino Laboratory
※ Facilities
※ Research Topics
R&D Program Henry T. Wong / 王子敬
Academia Sinica /中央研究院
@ Yong Pyong / 龍平*Taiwan EXperiement On NeutrinO http://hepmail.phys.sinica.edu.tw/~texono/
m2 – : Summary
PDG 2000: 2002
SK atm.
SNO solar
: Consistent Checks to atm. amLAND : picks LMA for solar n
SK
SNO Salt Results …..Solar LMA Solution (before Sept 03)
Neutrino Mass Structures :
m2
※ absolute scale unknown
Solar
Normal Vs Inverted Hierachy ??
Quasi-Degenerate Vs Hierarchical ??
Atm.
TEXONO* CollaborationW.C. Chang, K.C. Cheng, M.H. Chou, H.C. Hsu, C.H. Iong, G.C.Jon, F.S. Lee,
S.C.Lee, H.B. Li, V. Singh, D.S. Su, P.K.Teng, H.T.K.Wong, S.C. Wu Academia Sinica, Taipei, Taiwan
W.P. LaiChung Kuo Institute of Technology, Taipei, Taiwan
C.H. Hu, W.S. Kuo, T.R. YehInstitute of Nuclear Energy Research, Lungtan, Taiwan
H.Y. Liao, S.T. Lin, M.Z. WangNational Taiwan University, Taipei, Taiwan
F.K. LinNational Tsing Hua University, Hsinchu, Taiwan
Z.M. Fang, R.F. SuNuclear Power Station II, Kuosheng, Taiwan
J. Bao, K.J. Dong, S. Jiang, L. Hou, Y.H. Liu, H.Q. Tang, B. Xin, Z.Y. Zhou
Institute of Atomic Energy, Beijing, ChinaJ.Li, Y. Liu, J. Nie, Z.P.Mao, J.F.Qiu, H.Y.Sheng, P.L.Wang,
X.W. Wang, D.X.Zhao, P.P.Zhao, B.A.Zhuang Institute of High Energy Physics, Beijing, China
J.Q. Lu, T.Y. ChenNanjing University, Nanjing, ChinaY. An, D.Z. Liu, Q. Yue, Y.F. Zhu
Tsing Hua University, Beijing, ChinaC.Y. Chang, G.C.C. Chang
University of Maryland, Maryland, U.S.A.
Co-Prinicipal Investigators Ph.D. Students
HISTORYInitiate : Chang Chung-Yung 1996First Collab. Meeting/Official Start : October 1997First Paper : October 1998KS Reactor Experiment Installation : June 2000First Ph.D. : Liu Yan , July 2000First Physics Data Taking : June 2001.First Physics Results: Dec 2002.
TEXONO Overview
Poineering Efforts : “Zero-Background Experiment” ! KS Expt: 1st large-scale particle physics experiment in Taiwan
TEXONO Coll. : 1st big research Coll. % Taiwan & China
[feature report in Science, Vol. 300, 1074 (2003) ]
Program:Kuo-Sheng Reactor Neutrino Laboratory
※ reactor : high flux of low energy electron anti-neutrinos
※ m0 anomalous properties & interactions
※ physics full of surprises , need intense -source
study/constraint new regime wherever experimentally accessible
explore possible new detection channels
R&D Projects
Kuo-Sheng Nuclear Power Plant
KS NPS-II : 2 cores 2.9 GW
KS Lab: 28 m from core#1
Kuo-Sheng Neutrino Laboratory High flux of e (also ….. e )
Modular Design : independent detector, electronics, shielding
high-Z target, large e
Improved detector performance:
good energy & spatial resolution,
low threshold, separation
Elaborate electronics+DAQ+control sys.
complete record of pulse shape + timing info.
Elaborate Shieldings
radon purge & 4cosmic veto
Kuo Sheng Reactor Neutrino Laboratory
Front Gate
Configuration: Modest yet Unique
Flexible Design: Allows different detectors conf. for different physics
Inner Target Volume
Front View (cosmic vetos, shieldings, control room …..)
KS Expt: Period I Detectors
FADC Readout
[16 ch., 20 MHz, 8 bit]
ULB-HPGe [1 kg] CsI(Tl) [46 kg]
Multi-Disks Array [600 Gb]
Kuo Sheng Reactor Neutrino Laboratory : First Res
ults
See Hau-Bin Li ‘s Talk
Citation in AIP’s Physics News Update #631-1 (2003).
Reactor (e) Sensitivities
Sensitivities
KS Physics Program : Period I & II
HPGe [1 kg] : : x2 more data from PRL improved background & analysis study e flux from reactor dominated by 51Cr : ~ 10-3 (prelim.)
study possible nuclear transitions
e.g. 73Ge* decays by 2’s separated by =4.6 s
CsI(Tl) [186 kg] : attempt measurement of Standard Model (ee-)
sinw at MeV range
Prototype ULE-HPGe [5 g] : threshold < 300 eV ~ 100 eV explore potentials on N coherent scattering & CDM
ee
Reactor Neutrino Interaction Cross-Sections
P3+: Coh. (N) < 1 keV
P1: MM (e) 1-100 keV
P2: SM (e) > 2 MeV
Reactor as e Source
Fission Material
Fission Products
Neutrons
odd-odd nuclei
Structural
materials of reactor
Electron capture or + decay ( neglected )
νe Emission
CapturedCaptured
Mostly rich in
neutrons
¯ Decay back to stable valley
Anti-neutrino Emisson
Tagging of 73Ge ½- 2 transitions: Event-by-Event background-free tag with PSD
To do : Reactor ON/OFF analysis on the system ~1 s before the transition
To look for : possible -induced nuclear transitions
CsI(Tl) Array : Highlights
40 cm length (longest commercial prod.)
Energy+3D info: 10% FWHM at 660 keV
(z) <2 cm @ E>250 keV
Detector Threshold ~ 20 keV
PSD for : > 99%
Intrinsic Purity : 238U/
232Th < 10
-12 g/g (equil.)
40K < 10
-10 g/g
cosmic muon events on-site @ 46 kg target
Full Detector:
186 kg target on-site for Period-II
DAQ with large dynamic range
Period-2 CsI(Tl) Array : 186 kg, 93 crystals
Single Crystal QL Vs QR
(Raw Data)
Region of Interest for SM e)
Z = 0 cm
Z =40 cm
208Tl
40K 137Cs
Venktesh Singh‘s Talk
“Ultra-Low-Energy” HPGe Prototype
mass 5 g ; can be constructed in multi-array form
threshold <100 eV after modest PSD
background measurement on-site Nov 03
study appl. in coherent scattering and Dark Matter searches
Hau-Bin Li & Qian Yue’s Talk
ULE-HPGe Prototype Results
PSD Cut
Threshold ~ 100 eV
Signal Band
Threshold < 100 eV
R&D Projects Explore New Detectors Scenarios (LE, CDM …)
other crystal scintillators
ultra low energy HPGe [ O(100 eV) threshold ]
Feasibility Studies on CsI(Tl) for Dark Matter Searches
Approved Experiment @ Korea by KIMS Coll.
Upgrading FADCs (+ FPGA etc. capabilities…..)
for LEPS @ SPring8
Trace Radio-purity with AMS ( Accelerator Mass Spectrometry)
1st goal : sensitivity of 10-14 g/g in 40K
Sono-Luminescence Project (inter-disciplinary)
CsI(Tl) for CDM Searches(Feasibility Studies : TEXONO-CosPa Pr
oject) Potential Merits:
Better PSD for separation than NaI(Tl)
Minimal passive materials
Large target mass possible (c/f em-calor. 40 tons)
KIMS Expt. :
200 kg CsI(Tl) for CDM
in S. Korea
Highlights of R&D Program:
Quenching Factor measurements with neutron beam
lowest threshold data
1st direct measurement of diff. cross section in heavy nuclei
PSD studies with Neural Net. & Max. Likelihood
improve conventional methods
40 MHz ; 12 bit ; 32 ch/module @ 9 U VME [ c/f KS FADC : 20 MHz ; 8 bit ; 16 ch/module ] On-board processing with FPGA 1000 channels used in TPC in LEPS Expt. @ SPring8
TPC for LEPS @ SPring8
40 MHz sampling rate.10 bits resolution with 2Vp-p dynamic range.Clock distribution with Phase Lock Loop circuit.On Board digital signal delay and Real-Time ZERO-Suppression.High capacity First In First Out Memory.
Easy to use with high density connector.
Mixed signal FADC Adapter Board
TEXONO/KS FADC for SPring8/LEPS
(cosmic muon)
Trace Radio-purity with AMS
Based at AMS facilities @CIAE with 13 MV Tandem
Potential Merits:
small samples, quick
versatile on sample choice
sensitive to emitters
sensitive to stable isotope & extrapolate (e.g. 39K)
>103 improvements over ICP-MS
[.. once prescriptions are known. ]
Status : demonstrate 129I/127I < 10-12 g/g
measure 40K~10-10 g/g in CsI (powder)
Sensitivity goal : 10-14 g/g
Future : different bases e.g. liquid scintillator
87Rb …… [238U / 232Th series after Tandem upgrade]
Sonoluminescence Project a frontier subject with possible surprises
new directions : to explore subjects we do not know
Table-top experiments, pursue-able in several labs
balance the other big & long time-scale projects
use HEP approaches
Status :
produce steady SL
integrate DAQ
study physics
identify research topics ……..
SL Typical Set-Up SL Typical Cycle
SonoLum Pulse
Also ………. Geographically possible for medium baseline experiment for “13” :
Easy reach from city Access to Plant established Road tunnel at 2 km 100 m rock overburdenContacts with International Team
IHEP’s 13 Proposal at Daya Bay near Hong Kong (Li Jin’s talk)
TEXONO Collaboration: Built-Up and Growing Kuo-Sheng Neutrino Lab.: Established & Operational ※ Modular & Flexible Design Physics Data Taking since June 01 ※ Unique HPGe Low Energy Data ※ Bkg Level ~ Underground CDM Expt.
Results published on () Other analyses under way Period-II DAQ Improved HPGe Conf. 186 kg CsI(Tl) [(e) …] LEGe: study potentials for coh(N) Diversified R&D Program in parallel
TEXONO STATUS
Summary & Outlook
Neutrinos are important but strange objects history of physics full of surprises ! Strong evidenceS of massive ’s & finite mixings Physics Beyond the Standard Model ! More experiments & projects coming up EVEN MORE EXCITEMENT ! TEXONO is also a (modest) part of it Tremendous Pleasure & Pressure !