1. High Energy Particle Astrophysics PRC-US Collaboration Summary Report Gus Sinnis David Kieda Gus Sinnis Hu Hongbo Jordan Goodman Min Zha

2. What Do We Want to Learn? What are the origins of cosmic rays? –Are the accelerators of hadrons different from electrons? –How high in energy can galactic sources produce particles? –What are the sources of the UHECRs? How do astrophysical sources accelerate particles? –What is the role of the extreme gravitational an magnetic fields surrounding black holes and neutron stars? –How are particles accelerated within relativistic jets? Are there new classes of objects in the universe? Fundamental physics & cosmology –What is the EBL and how did it evolve? –What is the dark matter? –Does the speed of light depend on photon energy? –Are there primordial black holes?

3. What Measurements Required? Build a large observational database of the quiescent sky –Different source classes –Many objects from each class Build a database of transient phenomena –Active galactic nuclei –Gamma ray bursts Perform a complete sky survey –Point sources –Extended sources –Large-scale structure Perform detailed studies of individual objects –Morphology –Energy spectra Compare  -ray images with spectra & images with: –X-ray and optical images –Neutrino measurements

4. Active Galactic Nuclei  Rotating ~10 8 M sun black hole  Accretion powered ~10 48 ergs/sec  TeV emission is along jet  Hadrons or leptons accelerated?  Bulk Lorentz factor in jet (>30)  B-field in shock?

5. GeV/TeV Observation Techniques GLAST Direct  -ray detection Energy Range: 0.1-100 GeV Angular resolution: 0.1-3 0 Energy Resolution: 10% Field of View: 2.4 sr Detection Area: 1 m 2 On-time efficiency : > 90% $>100 M US VERITAS/HESS Cherenkov Light Detector Energy Range: 50 GeV-50 TeV Angular resolution: 0.05 0 Energy Resolution: 10% Field of View: 0.003 sr Detection Area: >10 4 m 2 On-time efficiency : 10% $12 M US MILAGRO Particle Detector Energy Range: 0.1-100 TeV Angular resolution: 0.5 0 Energy Resolution: 50% Field of View: > 2 sr Detection Area: >10 4 m 2 On-time efficiency : >95% $3 M US

6. R. ONG 2005 ICRC

7. Santa Fe 2006 40 Updated of R. ONG 2005 ICRC

8. 359° 330° HESS Galactic Plane Survey 30° 0° SNR PWN X-ray binary unknown At least 3 objects in the scan with no counterpart. As for  TeV J2032-4130 by HEGRA  HESS J1303-631

9. Dark accelerators?  TeV J2032+4130: Recent 50 ks Chandra obs. reveals no compelling counterpart (Butt et al. astro-ph/0509191)  GRB remnant ?? (Atoyan, Buckley & Krawcynski astro-ph/0509615) -TeV flux  huge E budget, yet no synchrotron… relativistic shock accel. of p +  not a single power law.  HESS J1303-631: Chandra, XMM) reveal no obvious counterpart. Archival ROSAT image, plus new Chandra image FOV (squares). Several pulsars - but none with sufficient spin- down flux for powering detectable TeV emission from a PWN. ~ 1  extent of HESS source. Mukherjee & Halpern astro-ph/0505081€

10. Milagro Sky Survey Crab Nebula ~14  Galactic Ridge clearly visible Cygnus Region discovery ~12  Preliminary

11. Milagro Cygnus Region Preliminary EGRET diffuse model EGRET sources A new TeV gamma-ray source

12. Diffuse Gamma Ray Emission Milagro preliminary Inner Galaxy (40-100)Cygnus Region (65-85) EGRET From A. Strong Milagro

13. Two dimensional observation on large scale anisotropy of TeV Cosmic-ray using the Tibet Air Shower Array (Preliminary)

14. Tibet III + MUON 8,640 m 2

15. ARGO Project  astronomy （ Sub-TeV ， 0.3I Crab ） Diffused γ sources （ Sub- TeV ） GRB （ 10GeV ） Knee Physics Anti-p/p （ 300GeV ） Primary Proton Spectrum （ 10TeV ） Solar Physics 120/154 clusters complete 90 o 31 ’ 50 ” E, 30 o 6 ’ 38 ” N 4300m a. s. l., 606g/cm 2

16. RPC DAQ ARGO

17. Smooth window radius = 1.5 °

18. miniHAWC and HAWC Milagro: 450 PMT (25x18) shallow (1.4m) layer 273 PMT (19x13) deep (5.5m) layer 175 PMT outriggers Instrumented Area: ~40,000m 2 PMT spacing: 2.8m Shallow Area:3500m 2 Deep Area:2200m 2 HAWC: 5625 or 11250 PMTs (75x75x(1 or 2)) Single layer at 4m depth or 2 layers at Milagro depths Instrumented Area: 90,000m 2 PMT spacing: 4.0m Shallow Area:90,000m 2 Deep Area:90,000m 2 miniHAWC: 841 PMTs (29x29) 5.0m spacing Single layer with 4m depth Instrumented Area: 22,500m 2 PMT spacing: 5.0m Shallow Area:22,500m 2 Deep Area:22,500m 2

19. miniHAWC Construction Prefabricated steel building 900k$ Building installation ~500 k$ Pond excavation ~800 k$ Liner cost ~700 k$ Total facility cost ~3.4M$ 170m 150m 4.5-5.0 m 6m

20. GRB Sensitivity Fluence Sensitivity to 100s GRB. Both Milagro and miniHAWC can “self trigger” and generate alerts in real time. GRB rate in FOV ~100 GRB/year (BATSE rate) Milagro miniHAWC

21. Potential miniHAWC Sites Sierra Negra, Mexico 4010m asl Chacaltaya, Bolivia 4800m Yangbajing, China 4300m

22. Geomagnetic Cutoff Milagro:3.5 GV Tibet- 13.1 GV La Paz: 12.0 GV Sierra Negra: 7.7 GV Singles rates at sites under consideration are reduced by ~20-30% due to improved geomagnetic cutoff.

23. Requirements on Observation Site high quality operation, low cost and long life-span: Altitude 4300m a.s.l. Topography flat and wide, plenty of space. Climate easy for construction, operation & living. Traffic accessible to highway, airport or railway station. Power existed electric power line network. Logistics not far from local town/modern city. Neighborhood 1000s of residents: clinic, post office, school … Communication Telephone, mobile phone, high speed optical fibre network (155Mbps today).

24. Detector Sensitivity (Single Location) miniHAWC HAWC GLAST EGRET Crab Nebula Whipple VERITAS/HESS Current synoptic instruments

25. Survey Sensitivity 4 min/fov 7 min/fov 1500 hrs/fov

26. Summary Gamma Ray astrophysics has entered a period of discovery –Dark sources, Galactic diffuse emission, extended sources Cherenkov telescopes and particle detection arrays offer complimentary views of the sky New instruments are coming online and planned which promise large increases in sensitivity YBJ is an excellent location for the next generation water Cherenkov detector Discussions continuing and we hope for collaboration in this endeavor Thank you for an excellent workshop!