1. Physics Program of TEXONO: Highlights
TEXONO Overviews
Kuo-Sheng Reactor Neutrino Laboratory
 Results on Neutrino Magnetic Moment
 Other Analysis Subjects being Pursued
 Present Status and Plans
R&D Program
Henry T. Wong / 王子敬
Academia Sinica / 中央研究院
@ IHEP + CIAE
September 2003

2. Congratulations to 2003 TEXONO Degrees
Ph.D.s :
Yue Qian 岳骞, IHEP (now at THU)
Xin Biao 辛標, CIAE (remains at CIAE)
M.Sc :
Liu Da-Zhi 劉大治, THU (now at MIT)

3. Poineering Efforts : “Zero-Background Experiment” !
TEXONO Overview
Program:
Kuo-Sheng Reactor Neutrino Laboratory
※ reactor : high flux of low energy electron anti-neutrinos
※ mn0  anomalous n properties & interactions
※ n physics full of surprises , need intense n-source
 study/constraint new regime wherever experimentally accessible
 explore possible new detection channels
R&D Projects
Poineering Efforts : “Zero-Background Experiment” !
KS Expt: 1st particle physics experiment in Taiwan
TEXONO Coll. : 1st big research Coll. % Taiwan & China
[feature report in Science, Vol. 300, 1074 (2003) ]

4. 

5. TEXONO* Collaboration
W.C. Chang¶, K.C. Cheng, M.H. Chou, C.H. Iong, G.C. Jon, F.S. Lee, S.C. Lee, H.B. Li,
D.L. Lin, F.K. Lin, S.T. Lin, V. Singh, D.S. Su, P.K. Teng, H.T.K. Wong†, S.C. Wu
Academia Sinica, Taipei, Taiwan
W.P. Lai
Chung Kuo Institute of Technology, Taipei, Taiwan
C.H. Hu, J.M. Huang, W.S. Kuo, T.R. Yeh
Institute of Nuclear Energy Research, Lungtan, Taiwan
M.Z. Wang¶
National Taiwan University, Taipei, Taiwan
J.H. Chao, J.H. Liang
National Tsing Hua University, Hsinchu, Taiwan
Z.M. Fang, R.F. Su
Nuclear Power Station II, Kuosheng, Taiwan
J. Bao, M. He, S. Jiang, L. Hou, Y.H. Liu, H.Q. Tang, B. Xin, Z.Y. Zhou¶
Institute of Atomic Energy, Beijing, China
J. Li†, Y. Liu, Z.P. Mao, J. Nie, J.F. Qiu, H.Y. Sheng, P.L. Wang, X.W. Wang,
D.X. Zhao, J.W. Zhao, P.P. Zhao, S.Q. Zhao, B.A. Zhuang
Institute of High Energy Physics, Beijing, China
Z.S. Liu, Z.Y. Zhang
Institute of Radiation Protection, Taiyuan, China
T.Y. Chen
Nanjing University, Nanjing, China
J.P. Cheng, D.Z. Liu, Q. Yue, Y.F. Zhu
Tsing Hua University, Beijing, China
C.Y. Chang, G.C.C. Chang†
University of Maryland, Maryland, U.S.A.
† Co-Prinicipal Investigators
¶ Project Leaders
Ph.D. Students
*Taiwan EXperiement On NeutrinO
Home
HISTORY
Initiate : Chang Chung-Yung 1996
First Collab. Meeting/Official Start : October 1997
First Paper : October 1998
KS Reactor Experiment Installation : June 2000
First Ph.D. : Liu Yan , July 2000
First Physics Data Taking : June 2001.

6. Kuo-Sheng Nuclear Power Plant
KS NPS-II : 2 cores  2.9 GW
KS n Lab: 28 m from core#1

7. Kuo Sheng Reactor Neutrino Laboratory
Front Gate
Front View (cosmic vetos, shieldings, control room …..)
Configuration: Modest yet Unique
Flexible Design: Allows different detectors conf. for different physics
Inner Target Volume

8. ULB-HPGe + Anti-Comptons
KS Expt. : Period I Configuration
Period I : June 01 – April 02 (60 days OFF)
Shielding & Veto [one side]
ULB-HPGe + Anti-Comptons
CsI(Tl) Array (46 kg)

9. KS Expt: Period I Detectors
ULB-HPGe [1 kg]
CsI(Tl) [46 kg]
FADC Readout
[16 ch., 20 MHz, 8 bit]
Multi-Disks Array [600 Gb]

10. mn with Reactor ne mn Experimental Probe:
 parametrize possible niL njR + g vertices
  both i = j “diagonal” &
i  j “transition” moments
Experimental Probe:
 Study ne + e-  nX + e-
 Focus on low recoil energy
※ sm  T–1
※ decouples SM “background”
[ ……… LE reactor f(ne) not accurately known]
 Look for Excess in Reactor ON/OFF
Neutrino Radiative Decay (Gn):
 sm & Gn related:
 same vertices – real g for Gn
Electron Recoil Spectra

11. PDG Limit : 1.5 X mB
(indirect seach from SK spectral shape)
an allowed solution for the solar neutrino data (before KamLAND)

12. KS/P1/Ge : Spectra & Residual
Based on 196/52 days of Reactor ON/OFF data
No anomalous structures or residuals

13. KS/P1/Ge/mn : Results (LHB Thesis)
Total 4712/1250 hours ON/OFF
 No residual observed
Range of O(1 cpd) background
c/f Dark Matter expt.
Fit OFF spectra to p5
Measure [fOFF;dfOFF ]
c2/dof = 80/96 )
Fit ON spectra to
fOFF + fSM + k2 fMM [10-10 mB]
Fit Results c2/dof = 48/49 ):
k2 = -0.4  1.3 (stat.)  0.4 (sys.)
Limits derived :
mn < 1.3 (1.0)  mB
@ 90(68)% C.L.
H.B. Li et al., TEXONO Coll., Phys. Rev. Lett. 90, (2003)

14. Reactor mn(ne) Sensitivities
Gn Sensitivities

15. Kuo Sheng Reactor Neutrino Laboratory : First Results

16. Citation in AIP’s Physics News Update :
2003
Related websites
Physics News Graphics
Physics News Links
American Institute of Physics
Online Journal Publishing Service
Back to Physics News Update
Number 631 #1, April 2, 2003 by Phil Schewe, James Riordon, and Ben Stein
The First-Ever Large China-Taiwan Scientific Collaboration
The first-ever large China-Taiwan scientific collaboration has carried out a reactor experiment which puts a new upper limit on the neutrino magnetic moment. Consider first the electron; it not only has electrical charge but also spin, which means that it will act like a tiny magnet. Even a neutral atom, because of its internal distribution of negative and positive charge, can have a nonzero magnetic moment. Consequently neutral atoms can be controlled, to some extent, by magnetic fields. But what about a neutrino? Neutrinos may well possess a small amount of mass, But what about magnetism? Can they effectively have a tiny bit of charge or internal structure? A nonzero neutrino magnetic moment provides the neutrino with a way to interact electromagnetically with the world; generally the neutrino is thought to interact only via the weak nuclear force. Evidence for nonzero magnetic moment would show up in several ways: in anomalous electron-neutrino scattering, in radiative decays in which the neutrino casts off a gamma ray, and in various astronomical settings, such as supernovas. The TEXONO collaboration, using neutrinos from the 2.9-GW Kuo-Sheng Nuclear Power Station in Taiwan, looked for a characteristic anomalous electron energy spectrum arising from electron-neutrino scattering. They did not see any such evidence, and from this they derive the best direct-laboratory upper limit on neutrino magnetic moment, 1.3 x times the magnetic moment of the electron (a unit also known as the Bohr magneton). The team also derives an indirect bound on neutrino radiative decays. (Li et al., Physical Review Letters, 4 April 2003; contact Henry Wong, Academia Sinica, Taiwan, ) The TEXONO Collaboration is supported by several research institutions and their respective funding agencies from Taiwan and China. An efficient flow of students and scientists moves in both directions.
Back to Physics News Update

17. Doppel-Null Neutrino bleibt unmagnetisch
                           Dienstag,                                                                                                                                                                                                                    
                                                                                                                
Doppel-Null Neutrino bleibt unmagnetisch
Auch Nicht-Ergebnisse liefern Physikern Einsichten – zum Beispiel der Versuch, an Neutrinos ein magnetisches Moment zu messen. Ein solches Moment kann theoretisch auch bei neutralen Teilchen wie Neutrinos entstehen, wenn eine Eigendrehung die negativen und positiven Ladungsanteile herumwirbelt. Deshalb suchten die Forscher nach subtilen Abweichungen von der – ohnehin extrem schwachen – Wechselwirkung von Neutrinos aus einem Kernreaktor mit Elektronen. Ihr Resultat: Null, wie bei früheren Experimenten. Allerdings haben sie die Null genauer vermessen; die Fehlergrenze liegt etwa beim zehnmilliardsten Teil des magnetischen Moments des Elektrons ( Physical Review Letters, Bd.90, Nr , 2003). Somit hält sich das Neutrino an die etablierte Theorie: Die elektromagnetische Wechselwirkung lässt es völlig kalt. Wärmer wurde hingegen das Verhältnis der beteiligten Forscher. Sie stammten aus der Volksrepublik China und aus Taiwan.

18. 科學人雜誌
(Scientic American/Chinese)
2003年5月號

20. Prototype ULE-HPGe [5 g] :
Status & Plans
HPGe [1 kg] :
mn + Gn : x2 more data
improved background & analysis
study ne flux from reactor
dominated by 51Cr : ~ (prelim.)
study possible nuclear transitions
e.g. 73Ge* decays by 2g’s separated by t1/2=4.6 ms
CsI(Tl) [186 kg] :
attempt measurement of Standard Model s(nee-)
 sin2qw at MeV range
Prototype ULE-HPGe [5 g] :
threshold < 300 eV  ~ 100 eV
explore potentials on nN coherent scattering & CDM

21. Reactor Neutrino Interaction Cross-Sections
P2: SM (ne) > 2 MeV
P1: MM (ne) keV
P3+: Coh. (nN) < 1 keV

22. Reactor as ne Source (Xin Biao’s Thesis) Fission Material
Fission Products
Neutrons
odd-odd nuclei
Structural materials of reactor
Electron capture or + decay ( neglected )
νe Emission
Captured
Mostly rich in neutrons
¯ Decay back to  stable valley
Anti-neutrino Emisson

23. Tagging of 73Ge ½- 2g 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 n-induced nuclear transitions

24. CsI(Tl) Array : Highlights
40 cm length (longest commercial prod.)
Energy+3D info:  10% FWHM at 660 keV
 s(z) <2 cm @ E>250 keV
Intrinsic Detector Threshold ~ 20 keV
PSD for g/a : > 99%
Intrinsic Purity :  238U/232Th < g/g (equil.)
 40K < g/g
Status:
186 kg target on-site for Period-II
DAQ with large dynamic range

25. Period-2 CsI(Tl) Array : 186 kg, 93 crystals
Single Crystal QL Vs QR (Raw Data)
Region of Interest for SM s(ne)

26. KS/P2:
93-Element
CsI(Tl) Array
(to be optimized)

27. 137Cs contamination in CsI ~556 events/day/kg
Background Spectra
(with all cuts; 1 module/ 2 kg ; about 1 week ; NOT fully optimized yet )
137Cs contamination in CsI ~556 events/day/kg
==> 2.3 X g/g (prelim.)

28. “Ultra-Low-Energy” HPGe Prototype
mass 5 g ; can be constructed in multi-array form
55Fe+Ti back-scattered Spectra : noise edge at 200 eV
threshold <100 eV after modest PSD
background measurement on-site Oct 03
study appl. in nN coherent scattering and Dark Matter searches

29. ULE-HPGe Prototype Results
Threshold ~ 200 eV
PSD Cut
Signal Band
Threshold < 100 eV

30. R&D Projects Upgrading FADCs (+ FPGA etc. capabilities…..)
Explore New Detectors Scenarios (LEn, CDM …)
 other crystal scintillators
 ultra low energy HPGe [ O(100 eV) threshold ]
CsI(Tl) for Dark Matter Searches
 CsI(Tl) CDM Korea by KIMS Coll.
Upgrading FADCs (+ FPGA etc. capabilities…..)
 for SPring8
Trace Radio-purity with AMS ( Accelerator Mass Spectrometry)
 1st goal : sensitivity of g/g in 40K
Sono-Luminescence Project (inter-disciplinary)

31. CsI(Tl) for CDM Searches
Potential Merits:
Better PSD for g/a separation than NaI(Tl)
Minimal passive materials
Large target mass possible (c/f em-calor. 40 tons)
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
N KIMS Expt. (apprd.) :
 kg CsI(Tl) for CDM
in S. Korea

32. TEXONO/KS FADC for SPring8/LEPS
40 MHz ; 12 bit ; 32 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 SPring8
TPC for SPring8
Mixed signal FADC Adapter Board
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.
(cosmic muon)

33. Trace Radio-purity with AMS
Based at AMS with 13 MV Tandem
Potential Merits:
 small samples, quick
 versatile on sample choice
 sensitive to a/b emitters
 sensitive to stable isotope & extrapolate (e.g. 39K)
 >103 improvements over ICP-MS
[.. once prescriptions are known. ]
Status :  demonstrate 129I/127I < g/g
 measure 40K~10-10 g/g in CsI (powder)
Sensitivity goal : g/g
Future :  different bases e.g. liquid scintillator
 87Rb …… [238U / 232Th series after Tandem upgrade]

34. 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 Cycle
SL Typical Set-Up

35. SonoLum Pulse

36. Also ………. Road tunnel at 2 km 100 m rock overburden
Geographically possible for medium baseline experiment for “ q13 ’’ search :
Easy reach from city
Access to Plant established
Road tunnel at 2 km
100 m rock overburden

37. Summary & Outlook 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 mn (Gn)  Other analyses under way
Period-II DAQ  Improved HPGe Conf.
 186 kg CsI(Tl) [s(ne) …]
 study potentials for scoh(nN) ……
Diversified R&D Program in parallel

38. TEXONO at present is rather like ..............
Thank You for Making This Happen !!!!
Hope WE can further Achieve Higher Grounds Together !