1. Recent Results in Neutrino Physics & Astrophysics
Neutrino Physics: WHY & HOW
Important recent results : solar + atm. + reactor n
TEXONO research program in Taiwan
 Kuo Sheng Reactor Lab
 Results on Neutrino Magnetic Moment
 R&D Program
Henry T. Wong / 王子敬
Academia Sinica / 中央研究院
@ IoP Colloquium
Nov 2003

3. Neutrino History 1914: continuous b-spectra (Chadwick)
1930: postulation of neutrinos (Pauli)
1934: theory of b-decay (Fermi)
calculation of s(np) (Bethe,Peierls)
1956: observartion reactor ne (Reines,Cowan)
1957: measurement of n helicity (Goldhaber)
1962: discovery of accelerator nm (BNL)
1968: observation of solar neutrinos (Davis)
1974: discovery of weak neutral currents (CERN)
1980’s >>>>>>> False Alarm on Neutrino Mass Measurements <<<<<<<<
1987: observation of supernova SN1987a n’s (IMB,Kamiokande)
1989: three families of light neutrinos (CERN)
1998: evidence of atmospheric neutrino oscillation (Super-Kam., …)
2000: observation of nt (Fermilab)
2001: evidence solar neutrino oscillation (SNO+SK+GALLEX ……)
2002: evidence of accelerator (K2K) & reactor (KamLAND) n’s oscillation
One of the most favorite subjects for Nobel Prizes ……

4. Nobel Prize in Physics (2002) 50% for n astrophys. :
Ray. Davis Jr. (U. Penn) :
“Classic” Chlorine Expt.
Masatoshi Koshiba 小柴昌俊 (U. Tokyo) :
Kamiokande & SuperK
Citations leave room for future prizes on n physics !!!
50% to Riccardo Giacconi, in X-Ray Astronomy

5. Neutrino Physics Road-Map
Grand Unified Theories (GUT)
L(n-mass)0
Structures & Compositions of Universe
mn’s;Uij’s 0
n-Oscil.
mn’s
n-decays
0nbb
b-spect.dist.
anomal. int.
……….
Particle Physics
Cosmology
Nuclear Physics
Astrophysics
n’s as Probe

6. Neutrino Sources n‘s everywhere: 300 per c.c.
Observed window
n‘s everywhere:
300 per c.c.
from sun, supernovae, cosmic rays, reactors, accelerators, astrophysical sources, & relic Big Bang …

7. Cross Sections Challenges of Neutrino Experiments :
Strong
Electro-magnetic
Weak
 l(H2O)  250 light years !
Challenges of Neutrino Experiments :
“How to Beat the Small Cross-Section?”
i.e. By building Massive Detectors
 while keeping cost/background Low !

8. Super-Kamionkande
※ Water Cerenkov detector: 50k tons, viewed by 11,000+ =50 cm PMTs in 1000 m underground site in central Japan
※ Physics: solar n, atmospheric n , long baseline accelerator n, proton decays ..
※ Accidents (PMTs imploded) Nov 01, 50% PMT data again end of 02 !!!

9. Atmospheric Neutrinos
nm disappearing, ne OK,
Strong evidence : > 15s
Better fits for nt appearing e n n
Atmospheric Neutrinos: Up-Down Asymmetry & Deficit

10. Solar Neutrinos

11. Measurement of Eccentricity of Earth’s Orbit !!!
The Sun IS Burning !!

12. KEK-SuperK (K2K) Accelerator n Flight path 250 km
Deficit of nm at far detector

13. Sudbury Neutrino Observatory (SNO)
※ Heavy Water Cerenkov detector: 1k ton, shielded
by 7k ton of water viewed by 9456 PMTs located
2000 m underground in Canada.
※ Physics: Solar n …

14. Pure D2O Phase
Actual measurements : only detect e- (a burst of light) : deconvolute the channels

15. Standard Solar Model + Standard Particle Physics Model
(also Cl, Ga, diff. E)
(also SK)
Standard Solar Model + Standard Particle Physics Model
( 5s effect )

16. Solar Neutrino Review :: Join forth-coming Seminar at ASIoP by
Dr. Alan Poon (Lawrence Berkeley Laboratory)
Dec 10, 2003.
*****************************
“ One of the Great Achievement in Science in the Past 40 years ! “

17. KamLAND
Long Baseline Reactor n (sensitive to 20% of world’s reactors !)
ave. flight path of 160 km
1 kton liquid scintillator in old Kamiokande site
probe “LMA” for solar n
historical results only 5 years from approved !!!!

18. Detects deficit of reactor ne-bar ; agrees LMA of solar neutrinos

19. Dm2 –  : Summary
2002
PDG 2000:
SK atm. n
SNO solar n

20. K2K : Consistent Checks to atm. n KamLAND : picks LMA for solar nSK

21. Solar LMA Solution (before Sept 03)
+ SNO Salt Results …..

22. Three Families of Neutrino Mixing
The Maki-Nakagawa-Sakata (MNS) matrix :
Possible CP Violation in n Sector:

23. Neutrino Mass Structures :
Normal Vs Inverted Hierachy ??
Quasi-Degenerate Vs Hierarchical ??
Dm2
Atm. n
Solar n
※ absolute scale unknown

24. Deeper Physical Questions ………..

25. Matter & Energy Density Budget in the Universe (2003)

26. Fermilab: NuMI to MINOS (2004+)
CERN: CNGS to Gran Sasso (2006+)
730 km
Both with 730 km baseline accelerator n beams
Precision measurement of atm. n’s q23
Explicit observation of nt
+ JHFSuperK (2007+)

27. IceCube High Energy Neutrino Telescope
Volume ~km3 !!

28. 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 large-scale particle physics experiment in Taiwan
TEXONO Coll. : 1st big research Coll. % Taiwan & China
[feature report in Science, Vol. 300, 1074 (2003) ]

29. 

30. TEXONO* Collaboration
W.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. Lai
Chung Kuo Institute of Technology, Taipei, Taiwan
C.H. Hu, W.S. Kuo, T.R. Yeh
Institute of Nuclear Energy Research, Lungtan, Taiwan
H.Y. Liao, S.T. Lin, M.Z. Wang
National Taiwan University, Taipei, Taiwan
F.K. Lin
National Tsing Hua University, Hsinchu, Taiwan
Z.M. Fang, R.F. Su
Nuclear 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, China
J.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. Chen
Nanjing University, Nanjing, China
Y. An, 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
Ph.D. Students
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.
First Physics Results: Dec 2002.

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

32. 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

33. 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]

34. 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

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

36. KS/P1/Ge/mn : Results 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)

37. Reactor mn(ne) Sensitivities
Gn Sensitivities

38. Kuo Sheng Reactor Neutrino Laboratory : First Results

39. Citation in AIP’s Physics News Update :
2003
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.
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2nd Entry for “Taiwan” / 1st Entry for “Academia Sinica” since 1991

40. 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.

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

42. 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

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

44. Period-2 CsI(Tl) Array : 186 kg, 93 crystals
Single Crystal QL Vs QR (Raw Data)
Z = 0 cm
Z =40 cm
208Tl
40K
137Cs
Region of Interest for SM s(ne)

45. “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 nN coherent scattering and Dark Matter searches

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

47. 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)

48. Also ………. Road tunnel at 2 km 100 m rock overburden
Geographically possible for medium baseline experiment :
Easy reach from city
Access to Plant established
Road tunnel at 2 km
100 m rock overburden
Contacts with International Team

49. TEXONO STATUS 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
※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

50. Summary & Outlook Neutrinos are important but strange objects
history of n physics full of surprises !
Strong evidenceS of massive n’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 !