1. Science Potential/Opportunities of AMANDA-II  S. Barwick ICRC, Aug 2001 Diffuse Science Point Sources Flavor physics Transient Sources 

2. Outline Diffuse science opportunties –Sub-PeV search –Trans-PeV search Search for point sources Effective volume and flavor physics Transient sources (GRBs, AGN bursts, etc) AMANDA-II/IceCube cooperation Conclusions

3. Messengers of Astronomy

5. AMANDA-II Atmospheric Muon Event 1.2 km !

6. Am-II Performance Improved A eff, especially near horizon Trigger –Majority trigger optimized for HE phenomena –String trigger optimized for <100 GeV ’s Angular resolution ~ 2 degrees

7. Am-II: Angular Sensitivity - atmospheric MC Trigger Level After BG rejection uphorizon Nearly uniform angular sensitivity to horizon ~200 atm per angular bin, precision calibration tool

8. Am-II MC: Energy response After BG rejection A eff (E) much improved compared to AMANDA-B10

9. Effective Area of Am-II A eff depends sensitively on the physics objective! Point source sensitivity is uniform to near horizon

10. Diffuse Flux AGN Core Convolved energy resolution New techniques  Anticipated sensitivity

11. Diffuse Flux AGN Core AMANDA window of opportunity KM 3 window New techniques 

12. Upper Bounds on Diffuse Flux AMANDA-II Anticipated sensitivity

13. Adopted from Learned and Mannheim(2000) Dotted curves are anticipated sensitivity Auger  Am-II (up) Am-II (down, E -2 )

14. Features for EHE search Am-II/B Aperture: V eff  ~ 20 km 3 sr 2 years of livetime on tape Calibration possible using in-situ N 2 laser –Equivalent to 200 TeV cascade in energy Background rejection “straightforward” –Total energy and “energy flow” variables –SPASE vetoes large  at relevant E CR

15. Extreme High Energy Science Earth becomes opaque to E  > 0.5 PeV –More efficient to search in “downgoing” direction –Most signal arrives from near the horizon  New search strategy and techniques are required

16. Downgoing Neutrino-induced Muon Flux Note: this plot is being updated-SWB

17. Angular distribution Down Up Most events are horizontal. EeV sources cut off very quickly below horizon. Direction provides additional BG reject.

18. Point Sources of  If spectra ~E -2, then order of magnitude improvement in sensitivity Search for ’s from TeV gamma sources –Limitations imposed by energy resolution

19. Point Source Atmospheric  + energy resolution

20. Point Source Focus on Mk501 as example

21. Mk501  Limits (E -2 ) AMANDA-II can test if    AMANDA-II (3 yr)E -2 Non E -2 spectrum requires larger array Superb  E

22. Mk501

23. Search for from TeV  Sources Milagrito all-sky search places limit at –Flux (>1 TeV) < 7 – 30 x 10 -7 m -2 s -1 –90% CL, E -2.5 AMANDA-II probes similar flux if  >1

24. V eff for AMANDA-II V eff ~ event rate V eff (  ) = 5-30 V eff ( e,   –Usually  e,  signatures are “contained events” Oscillation suggests comparable fluxes for all flavors  AMANDA-II provides evidence for measurable flux of e,  in km 3 arrays

25. Effective Volume of Am-II V eff (  ) is 0.3-0.5 km 3 R  > 10 km

26. Transient Phenomena Sources –GRBs External trigger vs. self-trigger TeV vs 100 TeV –SNa Sensitive to full volume of galaxy Models for TeV emission if not toward galactic center –AGN variability New time scales to reduce background Experimental Advantages -Reduce Atm BG -Extend search to lower energies -Search in downgoing direction for trans-PeV

27. Future: AMANDA-II +Ice3 Combination provides best overall performance Continuous science output during construction –E.g., Am-II + 18 strings surrounding AMANDA-II ~1 km 2 for GRB searches ~0.4 km 2 for E -2 sources Possible DAQ upgrade for AMANDA-II –Full waveform readout –Increase trigger rate by factor of 5

28. Conclusions AMANDA-II dramatically expands the discovery space for continuous, diffuse phenomena Significant extension of sensitivity for point searches –Energy resolution and atm. BG limits search for continuous emission from point sources V eff (  ) much larger than e,  –Correlated probe of flavor physics

29. Bottom Up Energetics of acceleration with B-fields –R g ~ 100 Z -1 (E/10 20 eV) (B/  G) -1 kpc –E < 10 18 Z (R/kpc) (B/  G) eV Three Problems! –GZK cutoff, - no candidate accelerators within 50Mpc –Few (if any) objects can accelerate to this energy –Event directions do not correlate with interesting objects Accelerate low energies to high energies

30. p+  CMB ->  + +n

31. Trans-GZK: way out New primary particles if M> 10 GeV –R-hadrons (SUSY of gluinos, quarks, gluons) (Problems: accelerator constraints) –Monopoles and bound states of monopoles (Problems: shower profile, no correlation with galaxy) Neutrino with  >10 5  SM (Problems: ad hoc, although extra-dimensions help) Z-burst (Weiler mechanism) –(Problems: enormous flux of at 10 22 eV)

32. Z-burst ~50 Mpc E ~10 22 eV v relic Z0Z0 Decays to 3N, 28  ±, 15  o Signatures:  /p large points to source directional pairing measurable flux E cut-off at m relic