1. The CRTNT Project (Cosmic Ray & Tau Neutrino Telescope) --- sensitivity and prototype experiment Huihai He, IHEP, CAS On behalf of the CRTNT collaboration TeVPA08

2. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment2 Outline Introduction CRTNT sensitivity to AGN neutrinos Two prototype telescopes @YBJ Summary

3. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment 3

4. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment 4 AGN 、  burst 、 GZK, TD, Z-burst … UHE μ e τ Air Shower Oscillation Fluorecsence Cerenkov light 2.5m 3m x16 F/C light telescopes

5. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment5 The CRTNT project 4 stations, each has 4 telescopes, covering 14  64  field of view. Site: Balikun, Xinjiang, China Energy range: E > 100TeV for neutrino, E > 0.1EeV for UHECR. UHECR Mountain-passing  event Earth-skimming  event

6. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment6 Physics Topics Traditional Physics Topics Diffusive flux from AGN, GRB and GZK Galactic Sources Pulsar may contribute VHE- flux, just next to diffuse AGN flux. However, Near-by galactic pulsar may be strong point source! (L.Zhang, 2006) SWIFT: near-by (Z<0.033) GRBs 500x more than predicted, neutrinos are more energetic (N.Gupta&B.Zhang, 2006) Cosmogenic neutrinos with IR background (T.Stanev on CRIS, 2006) New Physics beyond SM

7. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment7 Monte Carlo simulation Neutrino simulation (Mt. Balikun) Shower simulation Corsika shower lib Photon production & propagation (Direct Cerenkov, Fluorescence, Aerosol scattering, Rayleigh scattering) Sky light background (40/m 2 / μ s from measurement) Detector+electronics Cosmic ray background

8. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment8 y (15., -2.) (5., -3.) (-5., -2. ) S x FOV (62*14.5) zenith angle 83.5 (30., 2.)

9. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment9 D. V. Semikoz, G. Sigl, JCAP 0404:003, 2004 (hep-ph/0309328)

10. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment10 Neutrino event rate R: event rate (per year) N: number of primary neutrino per year contain CRTNT acceptance (area  solid angle [cm 2 sr ] ) and neutrino flux[cm -2 s -1 sr -1] -  : neutrino conversion efficiency (1.92*10 -4 ) -η: trigger efficiency (21.8%) D: duty cycle (15%) R =35.7/year (totally 10 8 neutrinos simulated)

11. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment11 Cosmic rays as background --- efficiency: 2.54%, ~30,000/year

12. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment12 Cerenkov (17.7%)horizontal (7.9%)very long(7.2%) up-going (41.5%) back-to mountain(5.8%) Neutrino Event Selection Before Reconstruction eff: ~80%, ~30/year 0.4 CRs

13. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment13 CRTNT sensitivity 1: ANTARES (1 year) 2: AMANDA-II (2000-2003, 807 days) 3: CRTNT (1 year) 4: CRTNT (3 years) 5: IceCube (3 years ) Feldman-Cousin method for upper limits (PRD, 2008 ) Assume F(En) = F0 En -2 90% C.L.

14. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment14

15. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment15 Online calibration sys. 1 Camera: 256 PMTs & Electronics on backboard 5m 2 spherical reflector & power supplies Telescope housing & trailer CRTNT

16. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment16 Data history FADC: 50MHz  20ns Narrow signals are shaped to >3 FADC bins 300 bins/history 3 histories/event two 10-bits FADCs (high/low gain)/PMT  3.5 orders of dynamic range Trigger threshold online adjustable

17. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment17 Trigger Algorithm Trigger pattern: Cerenkov: round Fluorescence: line Trigger mode: mono  local Stereo  global Telescope trigger Global Event trigger Trigger Mode Local Event trigger & >1>1 oror & Event processed Pattern Recognition Com PC104-DIO Telescope Trigger & Local Trigger

18. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment18 YBJ Sky background Star trajectory-pointing calib (<0.3 deg.) Test on DC coupling & PMT responses Stability of telescopes during hours of operation Relative gain calib. with LED (each day)

19. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment19

20. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment20 Basic distributions

21. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment21 CRTNT FOV Offline coincidence with ARGO GPS timing: <100ns Coincidence efficiency: 80% ARGO CRTNT

22. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment22 Offline coincidence with ARGO Energy threshold:~10TeV

23. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment23 Summary CRTNT is complimentary to underground neutrino detectors watching the southern hemisphere ~30 AGN neutrinos can be detected by CRTNT vs. 0.4 CRs per year, Upper limits (90% C.L.): 6.7 (eV.s -1.sr -1.cm -2 ) in three years CRTNT is as effective as IceCube with much lower cost. 2 prototype telescopes are completed and tested at YBJ, Tibet. CRs are observed coincident with ARGO-YBJ RPC carpet array Study of cosmic ray spectrum in the Knee region with the prototype telescopes is undergoing Scan for cosmic ray background as a function of elevation

24. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment24 Acknowledgements We are very grateful to the ARGO-YBJ Collaboration for the authorization to use the data of the ARGO-YBJ experiment Thanks!

25. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment25

26. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment26 Optimal thickness Most of the effective interaction occur within few decay length inside mountain. L m ~ 80 m L m ~ 625 m L m ~ 4.5 km L m ~ 30 km L m ~ 150 m

27. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment27 Maximum efficiency Maximum   efficiency  »   P    /  1/  N  E -0.37   E  P   E 1.37

28. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment28 Total photon-electrons The total photon-electrons are :

29. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment29 Cosmic Ray Background 3x10 4 CRs/yr (70 o ~75 o ) CR Energy CR Zenith angle Energy Zenith angle

30. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment30 Neutrino Interaction CC NC CC NC ： ν+N  ν+N’ CC ： ν+N  l +N’ CC Regeneration: ~1% tau loss: ~1% ~1%

31. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment31 interaction cross-section  N  E 0.37 1/ = N A ×  ×  N   : neutrino current cross- section,  + N   + X  : rock density = 2.65 g/cm 3  =  × c × T   (E  /10 15 eV) ×49.02 m E  = (1-y) E where y is fraction of energy carry out by interacting nucleon,  y  ¼, So E   ¾ E

32. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment32 Tau energy loss (1) Bremsstrahlung (2) Pair production (3) Photonuclear interactions (4) Ionization

33. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment33 Tau Decay ~17.8% ~17.7%

34. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment34 Sharada et al., hep-ph/050428

35. Huihai He ， 2008-9-28 The CRTNT sensitivity and prototype experiment35 P  : Conversion efficiency in mountain Blue : No dE/dX Red: w. dE/dX