1. The TEXONO Program in Neutrino and Astroparticle Physics: Overview and Plans
V. Singh (On behalf of the TEXONO Collaboration) Institute of Physics Academia Sinica, Taipei Taiwan
u Introduction u Kuo-Sheng Period – I Program - CsI Array, photos, performance etc. u Kuo-Sheng Period – II Program - New HPGe configurations + first results, Period I HE spectra and SM curve - CsI Array, photos, performance, background etc. u R & D Programs u Summary

2. TEXONO: Personnel Highlights 2002-03
l Ph.D. for Li Hau-Bin, NTU (June 2002) on neutrino magnetic moment analysis l Ph.D. due in   - Yue Qian, IHEP, on Dark Matter Feasibility Studies  
- Xin Biao, CIAE, on reactor electron neutrino calculation and analysis l New Ph.D. student : Lin Shin-Ted, NTU l Postdoc Chen Chin-Ping :   - faculty appointment at Peking U. l Beijing Tsing Hua University joined   - participation of M.Sc students l under discussion : joining of a Mexican cosmic-ray group

3. Kuo-Sheng Nuclear Power Plant
KS NPS-II : 2 cores X 2.9 GW
KS n Lab: 28 m from core#1 108 m from core#2 Overburden ~ 10 m concrete Flux=5.6*10^12/cm^2 s

4. Kuo-Shung Expt.: Period I (June01-April02) Detectors
ULB-HPGe [1 kg]
CsI(Tl) [46 kg]
FADC Readout
[16 ch., 20 MHz, 8 bit]
Multi-Disks Array [600 Gb]

5. Kuo-Shung Period – I Ge : Results Limits On : (Submitted in PRL)
Based on 196/52 days of Reactor ON/OFF data
No anomalous structures or residuals
Det. Threshold 5 KeV
Bkg. ~1/KeV-Kg-day above 12 KeV
Limits On : (Submitted in PRL)
mn < 1.3 (1.0) X mB @ 90(68)% C.L.
Li H.B. Talk Feb.,14, 2003

6. CsI(Tl) Array/P-I : Highlights & Technical Run
40 cm length (longest commercial prod.)
Energy+3D info:  10% FWHM at 660 keV
 s(z) <2 cm @ E>250 keV
Detector Threshold ~ 20 keV
PSD for g/a : > 99%
Intrinsic Purity :  238U/232Th < g/g (equil.)
 40K < g/g

7. Radon Purge Plastic Bag

8. Selected Photos – Period - II Installation – HPGe

9. Improvement in Period- II :Ge
 4p anti-Compton coverage
 improved inner shielding
 Aim of analysis threshold: ~ 5 keV
 study “ultra-low” energy Ge prototype [threshold : eV]
Event/KeV/day in KeV = P-II = P-I Event/KeV/day in KeV = P-II = P-I

10. Selected Photos – Period - II Installation – CsI(Tl) Array

11. Shielding inside the Target Volume
June 2001 (For Period – I)
Jan (For Period – II)

12. Steady Increment of CsI(Tl) Channels
From 14 to 180+
Better Shielding
Improved Results
Proto-type
Phase – I
Phase – II

13. Period-2 CsI(Tl) Array : 186 kg, 93 crystals
Single Crystal QL Vs QR
137 Cs
40 K

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

15. Reactor Neutrino Interaction Cross-Sections
P-III+: Coh. (nN) < 1 keV
P-II: SM (ne) > 2 MeV
"Standard Model n - e scattering" - related to fundamental electroweak parameters Sin**2 (qw) - observed but NOT measured at MeV range - detection channel for many solar neutrino experiment
P-I: MM (ne) keV

16. R&D Projects Upgrading FADCs
Explore New Detectors Scenarios
 loaded crystal scintillator (GSO, YbAG, LSO …..) [Published in NIM A 432, 111 (1999)]
 ultra low energy HPGe [ O(100 eV) threshold ]
CsI(Tl) for Dark Matter Searches
Upgrading FADCs
Trace Radio-purity with AMS ( Accelerator Mass Spectrometry)
Sono-Luminescence Project (fermenting ……..)
Close Contact with :  CsI(Tl) CDM Korea  JHFBeijing LBL n IHEP  Ultra HE (1015 eV) n NTU

17. 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 [Published in PL B and NIM (2002)]
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

18. TEXONO/KS FADC for SPring8
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 to be used in TPC in LEPS SPring8 by End 2002.
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.
Prototype Measurements :
(cosmic muon)

19. 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 [Published in NIM A479, 498(2002)]
Future :  different bases e.g. liquid scintillator
 87Rb …… [238U / 232Th series after Tandem upgrade]

20. Summary TEXONO Collaboration: Kuo-Sheng Neutrino Lab.:
 Built-Up and Growing
Kuo-Sheng Neutrino Lab.:
 Established & Operational
※Modular & Flexible Design
 Physics Data Taking since June 01-April02
※Unique HPGe Low Energy Data
※ Bkg Level ~ Underground CDM Expt.
Results on mn (Gn)
※ Other speculative analyses under way ※ Submitted in PRL
Period-2 DAQ
 Improved HPGe Conf.
 Commissioning 186 kg CsI(Tl) [+ s(ne) …]
Diversified R&D Program in parallel

21. Full TEXONO* Collaboration Author List
W.C. Chang¶, C.P. Chen, K.C. Cheng, H.C. Hsu, F.S. Lee, S.C. Lee, S.T. Lin,
D.S. Su, V. Singh, P.K. Teng, W.S. Tse¶, H.T.K. Wong†, C.S. Wu, 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
H.B. Li, 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
M. He, S. Jiang, L. Hou, 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,
Q. Yue, 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
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
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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.