1. Weihai, July 8-12 New Physics from the Sky 朱守华, Shou-Hua Zhu ITP, Peking University In collaboration with Xiao-Jun Bi, Jia Liu, Peng-Fei Yin and Qiang Yuan

2. Weihai, July 8-12 Title is motivated by ‘Dream of Red Chamber’

3. Weihai, July 8-12 Based on: Jia Liu, Peng-fei Yin, Shou-hua Zhu, Phys. Rev. D 77, 115014 (2008), arXiv:0803.2164. Peng-fei Yin, Jia Liu, Qiang Yuan, Xiao-jun Bi and Shou-hua Zhu, arXiv:0806.3689.

4. Weihai, July 8-12 Contents 1.Motivation 2.Neutrino Signal from DM annihilation in the Sun 3.Neutrino Signal from DM annihilation in the Milky Way

5. Weihai, July 8-12 1. Motivation

6. Weihai, July 8-12 3 major ways to detect dark matter 1.Missing energy at collider-based modern detector 2.Recoil energy of nucleus due to the scattering with dark matter (direct method) 3.Stable particles (neutrino, photon, etc.) due to dark matter annihilation (indirect method)

7. Weihai, July 8-12 Dark matter at colliders LHC & Tevatron: PP->Z(->leptons)h(->missing energy) Zhu, EPJC(2006) Higgs boson related to dark matter? Zhu, CPL(2007) PP-> H -> h(->bottom pair) h(->missing energy) Li, Yin and Zhu, PRD(2007) BEPC: e + e - -> gamma+ U(-> missing energy) Zhu, PRD(2007)

8. Weihai, July 8-12 Neutrinos from the DM annihilations High energy Neutrinos (MeV~TeV, depending on cold DM mass) can be produced by dark matter annihilations. Interactions of neutrino with matter in the standard model (see next figure)

9. Weihai, July 8-12

10. Pros and Cons Disadvantages: It’s hard to be detected such neutrinos in this energy range and with low flux. Large area neutrino telescope is needed! We can detect these neutrinos (actually charged muon) by large volume Cerenkov detectors, such as Super-kamiokande, IceCube, ANTARES…

11. Weihai, July 8-12 Advantages: neutrinos are hardly energy loss and trajectory deflection during the propagation. They may preserve the information of the nature and distribution of the DM, provided that the source is near (Sun and Milky Way).

12. Weihai, July 8-12 2. Neutrino Signals from Solar Neutralino Annihilations in AMSB model Jia Liu, Peng-fei Yin, Shou-hua Zhu, Phys. Rev. D 77, 115014 (2008), arXiv:0803.2164.

13. Weihai, July 8-12 How to estimate muon flux detected by IceCube? We need to know: Neutrino from neutralino annihilation in the Sun Neutrino propagation from Sun to Earth Converting to muon and detected at IceCube

14. Weihai, July 8-12 Neutrino signal from Solar center Dark matter scatters off nucleus in the Sun Trapped by gravity of the Sun Annihilation rate equilibriums capture rate Astrophys.J.321.338(1992)

15. Weihai, July 8-12 Neutrino signal from Solar center Scattering of nucleus and neutralino Spin-dependent(SD) interaction Mainly axial-vector interaction Exchanging Z, squark In our paper, SD is dominant Experiments in 07 Spin-independent (SI) interaction Scalar interaction Exchanging H,h,squark Dominant in heavy nuclei XENON10 for a 100GeV WIMP PRD48,5519(1993) PRD44,3021(1991) PRL 100 ， 021303 0805.2939v1

16. Weihai, July 8-12 Dark matter annihilation in Anomaly Mediated Supersymmetry Breaking Model In AMSB SUSY breaking via superconformal anomaly Free parameter of Minimal AMSB Wino-like neutralino Mainly annihilate to WW pair Other channel-ZZ, Zh, top pair

17. Weihai, July 8-12

20. Helicity effects and secondary neutrinos Transverse polarized W boson Leptonic decay and hadronization By spin and momentum conservation

21. Weihai, July 8-12 Other annihilation channel Z boson in Zh channel is longitudinal polarized ZZ is similar to WW

22. Weihai, July 8-12 Propagation of neutrinos to Earth Density evolution equation of propagation Vacuum oscillation Neutrino scattering Neutrino absorption and tau-neutrino re- injection Monte carlo simulation-WimpSim hep-ph/0506298

23. Weihai, July 8-12 IceCube neutrino detector Surpass the sonic barrierMuon surpass the speed of light Cerenkov light passing through the IceCube neutrino detector Courtesy Steve Yunck/NSF

24. Weihai, July 8-12 IceCube neutrino detector

25. Weihai, July 8-12 Atmosphere neutrino background Cosmic ray interacts with atmosphere around the Earth, produces high energy neutrinos which can result in muons in detector Such neutrino have no special direction, thus can be reduced by angle cut of IceCube

26. Weihai, July 8-12 Angular distribution of muons Angle of muon velocity In range Most of Muons are within 2 degree Important information to reduce spherical homogeneous atmosphere neutrino background

27. Weihai, July 8-12 Muon spectrum and backgrounds

28. Weihai, July 8-12 Benchmark Points

29. Weihai, July 8-12 A rule in thumb Possible to observe muons at IceCube if

30. Weihai, July 8-12 Summary for part 2 Neutralino annihilation in Sun produces high energy neutrinos Neutrinos propagate to IceCube from Sun The condition for muon detection in AMSB The angular distribution of signal muons Angular distribution is crucial to reduce atmosphere neutrino backgrounds

31. Weihai, July 8-12 3. Constraints on the Dark matter Annihilations by Neutrinos with Substructure Effects Included Peng-fei Yin, Jia Liu, Qiang Yuan, Xiao-jun Bi and Shou-hua Zhu, arXiv:0806.3689.

32. Weihai, July 8-12 Motivation Cross section of neutrino and matter increases rapidly with the increment of neutrino energy No excess observed for atmospheric neutrino up to 10 TeV Constraints for high energy neutrino flux

33. Weihai, July 8-12 Why DM substructure? Take visible matter as example!

34. Weihai, July 8-12 Why substructure? The principal component of the Solar System is the Sun, that contains 99.86% of the system's known mass and dominates it gravitationally Jupiter and Saturn, the Sun's two largest orbiting bodies, account for more than 90% of the system's remaining mass.

35. Weihai, July 8-12 Why substructure? Galactic center (GC) has the largest neutrino flux due to DM annihilation. However GC has also the largest backgrounds, for example black hole. Substructure may be background free, and ‘bright’ enough.

36. Weihai, July 8-12 How to proceed? We need to know: Galactic DM and substructure distribution Constraint on the dark matter annihilation cross section by atmospheric neutrino

37. Weihai, July 8-12 The neutrino flux from the DM annihilations depend on the particle property depend on the spatial distribution of DM

38. Weihai, July 8-12 Astrophysical factor of the DM annihilation To account for the contribution of substructures, we use We fix the smooth distribution of DM to NFW profile The average astrophysical factor is defined as is the half angle of the cone centered at the direction of the GC

39. Weihai, July 8-12 Galactic DM distribution profile A general DM distribution profile that fits the simulations is : Different parameters denote deferent profiles. NFW profile: 1.5, 3.0, 1.5 Moore profile: 1.0, 3.0, 1.0 Especially the cored profile could be or other cuspy form. J. F. Navarro et al., Astrophys. J. 490, 493 (1997). B. Moore et al., Astrophys. J. 499, L5 (1998). A. Burkert, Astrophys. J. 447, L25 (1995).

40. Weihai, July 8-12 Determination of the profile parameters We require the virial mass Virial radius amplifying factor over the background critical density of the universe Concentration parameter The unknown parameters and can be determined by. Generally this relationship is fitted from the numerical simulation. J. S. Bullock et al., Mon. Not. Roy. Astron. Soc. 321, 559 (2001)

41. Weihai, July 8-12 Determination of the profile parameters In our work, we use two models to determine the We use the fitted polynomial form and extrapolate to low masses ENS01 B01 The above models are from the simulations which generate sub-halos within a distinct halo. For the host ones, B01-sub or B01X2 J. S. Bullock et al., Mon. Not. Roy. Astron. Soc. 321, 559 (2001). V. R. Eke et al., Astrophys. J. 554, 114 (2001). J. S. Bullock et al., Mon. Not. Roy. Astron. Soc. 321, 559 (2001). S. Colafrancesco et al., Astron. Astrophys. 455, 21 (2006).

42. Weihai, July 8-12 Determination of the profile parameters The relation of at epoch Z=0

43. Weihai, July 8-12 The Galaxy halo and substructure We adopt as the mass of the Galaxy halo. Simulations give the number density of sub-halos an isothermal spatial distribution and a power-law function we adopt core radius, sub-halos mass range: Tidal effect: In the inner region of the host halo, strong tidal force tends to destroy the sub-halo. We find the mass fraction of substructure is about 14%.

44. Weihai, July 8-12 Astrophysical factor of the DM annihilation Astrophysical factor with concentration models as ENS01

45. Weihai, July 8-12 Astrophysical factor of the DM annihilation Astrophysical factor with concentration models as B01

46. Weihai, July 8-12 Astrophysical factor of the DM annihilation Astrophysical factor with concentration models as B01X2

47. Weihai, July 8-12 DM substructure as point-like source The massive sub-halo can be treated as point-like source and may be identified by high angular resolution detector. We use a Monte-Carlo method to generate average within the cone with half angle

48. Weihai, July 8-12 Astrophysical factor of the DM annihilation

49. Weihai, July 8-12 Atmospheric neutrino The main backgrounds detected by Cerenkov detectors are from cosmic ray interacting with the atmosphere of the earth, which have no special direction. There are no excess beyond the theoretical prediction of the atmospheric neutrino. The null results can be used to set the upper bound of the DM annihilation cross sections. We use the flux of atmospheric neutrino from M. Honda et al. Phys. Rev. D 75, 043006 (2007).

50. Weihai, July 8-12 Particle Physics factor of the DM annihilation We use the assumption that the productions of DM annihilation are only neutrinos. In fact DM may annihilation into final states other than neutrinos. Moreover high energy neutrinos from the DM annihilation will lead to gauge bosons bremsstrahlung The spectrum of neutrinos per flavor is a monochromatic line we average neutrino flux within the energy bin around J. F. Beacom et al., Phys. Rev. Lett. 99, 231301 (2007) ; H. Yuksel et al., Phys. Rev. D. 76, 123506 (2007). M. Kachelriess, P.D. Serpico, Phys. Rev. D 76, 063516 (2007) ; N. F. Bell et al., arXiv: 0805.3423.

51. Weihai, July 8-12 Final Results By requiring the neutrino flux does not exceed the atmospheric neutrino flux, we give the upper bound to the DM annihilation cross section.

52. Weihai, July 8-12 Summary for part 3 By requiring the DM induced neutrino flux less than the measured ones, we give the improved upper bounds on the DM annihilation cross section. Considering substructure average contribution over all directions, the bound are improved by several times. Considering single massive sub-halo as point source, the bound can be improved by 10^1~10^4 utilizing the angular resolution of IceCube. In some model, IceCube can achieve the sensitivity of DM annihilation cross section as 10^-26 cm^3s^-1.

53. Weihai, July 8-12 4. Summary of the talk Besides the central issue of electroweak symmetry breaking, LHC may also touch the properties of dark matter. More information of dark matter may come also from the sky, i.e. from the observation of neutrino by neutrino telescope (with excellent angular resolution). Thank you!

54. Weihai, July 8-12 Dark Matter Non-luminous matter with gravitation effects Galactic rotation curves Cold dark matter by analyses of structure formation WMAP From SUSY07 public lecture 来自 PDG

55. Weihai, July 8-12 Candidate for Dark Matter Conditions Stable on cosmological time scales Very weak electromagnetic radiation Right relic density Candidates Weakly interacting massive particles(WIMP) -Neutralino in Supersymmetry Primordial black holes, Axions 来自 PDG

56. Weihai, July 8-12 Experiment for Dark Matter Direct WIMP search Detection of nuclear recoils Cryogenics detector, Noble liquid No positive identification XENON10 Indirect WIMP search WIMP annihilation and decay Photon, neutrino, positron, anti-nuclei PRL 100 ， 021303

57. Weihai, July 8-12 DM detected methods We confirm the existence of the DM only through the gravitational effects, the rotation curves of spiral galaxies, the gravitational lensing, the dynamics of galaxy clusters… Collider detection, LHC, ILC… Direct detection, XENON, DAMA, ZEPLIN, CDMS… Indirect Direct detection, Gamma-Ray experiments, Ground-based, MAGIC, HESS, ARGO… Space-based, GLAST, EGRET… Anti-matter experiments, HEAT, BESS, AMS… Neutrino experiments, Super-kamiokande, IceCube, ANTARES…

58. Weihai, July 8-12 Other strategies of detecting neutrinos Explore the neutrinos from the extra-galactic explore the neutrinos from the galactic center (GC) H. Yuksel et al., Phys. Rev. D. 76, 123506 (2007). J. F. Beacom et al., Phys. Rev. Lett. 99, 231301 (2007).