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Next Generation Particle Astrophysics with GeV/TeV -Rays. D. Kieda University of Utah. Outline. Quick VERITAS Update GeV/TeV -rays and Dark Matter searches GRBs GeV/TeV emission Diffuse and point source angular/energy ranges R oadmap for future -ray observatories.
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Next Generation Particle Astrophysics with GeV/TeV -Rays D. Kieda University of Utah
Outline • Quick VERITAS Update • GeV/TeV -rays and Dark Matter searches • GRBs GeV/TeV emission • Diffuse and point source angular/energy ranges • Roadmap for future -ray observatories
VERITAS Telescopes-1 & 2 499 PMT camera • Davies-Cotton f/1.0 Optics. Total area=110m2 • Operational at Whipple Basecamp at Mt. Hopkins (1275m) in February 2006 Steel OSS Control Room
1.8 m 3.5º FOV Camera • 499 PMTs • Photonis XP2970 • 0.15º spacing
VERITAS:1-2Stereo Observations of Mrk 421April-May , 2006Wobble mode: ~10 sigma/30 minutes
VERITAS Update • 2 VERITAS telescopes operational at Mt. Hopkins (Feb 2006) • T3, T4 additional telescopes under construction now (First light T3: 9/2006; T4: 10/2006) • Expect full 4 telescope array operation by end of 2006. T3 assembly (June 9, 2006) T1 & T2 (Dec 2005)
2006 R. ONG 2005 ICRC
Updated of R. ONG 2005 ICRC 40 Santa Fe 2006
* * * Physics/Astrophysics with GeV/TeV -rays Active Galactic Nuclei Extragalactic Background Light Gamma Ray Bursts Shell-type Supernova Remnants Galactic Diffuse Emission Gamma-ray Pulsars Plerions Unidentified Galactic EGRET Sources Dark Matter (Neutralino) SN Nucleosynthesis/Cosmic Ray Origin Lorentz symmetry violation (Quantum Gravity)
mSUSY Dark matter Search:Neutralino-antiNeutralino annihilation Integrate annihilation cross sections to predict gamma ray energy spectrum over Dark Matter Galactic Halo density/velocity profiles But: Galactic Halo density profile for r<1kpc mostly based upon N-body simulations -> Only see strong signal if cusp in DM profile ->large variations in predicted GeV/TeV gamma ray production rate ->Galactic Mergers may reduce/eliminate cusps -> Cusps may also form in Galactic Halo?
HESS Sag A* Spectrum Profumo-Dark Matter Conf. UCLA 2006
Diffuse Emission in the GC Region (HESS 2006)
N-body simulations of DM Cusp formation in Halo • DM cusps form in Halo as well as Galactic Center • Cups region may persist & be dark (except for DM annhilation) • High Galactic Latitudes may be easier to observe DM annhilation than GC • Need unbiased all-sky survey with large detection area (>104 m2) to detect. • Unable to use optical, radio surveys to predict source regions Dieand,Kuhlen & Madan2006
Gal. Centre HESS J1804-216 HESS J1825-137 HESS J1837-069 HESS J1834-087 HESS J1813-178 G0.9+0.1 30° 0° 359° 330° HESS J1614-518 HESS J1640-485 RX J1713.7-3946 HESS J1616-508 The H.E.S.S. Survey Galactic Plane 230 h in 2004, 500 pointings; sensitivity 2% of Crab above 200 GeV 8 new sources @ > 6 s post-trial (+3 known)
Gal. Centre HESS J1804-216 HESS J1825-137 HESS J1837-069 HESS J1834-087 HESS J1813-178 G0.9+0.1 30° 0° 359° 330° HESS J1614-518 HESS J1640-485 RX J1713.7-3946 HESS J1616-508 The H.E.S.S. Survey Galactic Plane LS 5039 HESS J1632-478 HESS J1702-420 HESS J1745-303 HESS J1713-381 HESS J1708-410 HESS J1634-472 230 h in 2004 8 new sources @ > 6 s post-trial (+3 known) 6 new sources @ > 4 s post-trial Aharonian et al, Science (2005) Aharonian et al, ApJ (2006)
30° 0° 359° 330° Classes of Objects / Counterparts SNR PWN X-ray binary
30° 0° 359° 330° Classes of Objects / Counterparts At least 3 objects in the scan with no counterpart. SNR PWN X-ray binary As for TeV J2032-4130 by HEGRA HESS J1303-631 unknown
New Unidentified HESS Objects: • In the Galactic Plane • Extended (Diffuse) emission • Are there More Sources at High Galactic Latitudes?
TeV J2032+4130: Recent 50 ks Chandra obs. reveals no compelling counterpart (Butt et al. astro-ph/0509191) Dark accelerators? • HESS J1303-631: Chandra, XMM) reveal no obvious counterpart. • 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. Mukherjee & Halpern astro-ph/0505081€ ~ 1 extent of HESS source. 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.
Microquasar Detected! LS 5039 ~1.4% Crab (>100 GeV) The only point-like source in the HESS Galactic Plan scan.
Next Generation Observations Horan & Weeks 2003
Next Generation Observations • All-sky GeV/TeV survey with good sensitivity/ large area • Deep follow-up with high angular resolution/energy resolution • Ability to map large scale, diffuse structures • Lower energy threshold/faster response times for GRBs
MILAGRO Particle Detector Energy Range: 0.1-100 TeV Angular resolution: 0.50 Energy Resolution: 50-100% Field of View: > 3 sr Detection Area: >104 m2 On-time efficiency : >90% $3 M US GLAST Direct -ray detection Energy Range: 0.1-100 GeV Angular resolution: 0.1-30 Energy Resolution: 10% Field of View: 2.4 sr Detection Area: 1 m2 On-time efficiency : > 90% $>100 M US VERITAS/HESS Cherenkov Light Detector Energy Range: 50 GeV-50 TeV Angular resolution: 0.050 Energy Resolution: 10% Field of View: 0.003 sr Detection Area: >104 m2 On-time efficiency : 10% $12 M US GeV/TeV Observation Techniques
Energy Ranges • Inaccessible to Particle detectors • Cherenkov: low Cherenkv light density ->20-30 m diameter mirrors, high altitude? • Satellite: only a few photons: difficult spectra • Particle detectors ok • Cherenkov: 10 m diameter mirrors; low gamma ray rate, 1 km2 array , larger f.o.v. • Satellite: very few photons: no spectra • Particle detectors good • Cherenkov: 6 m diameter mirrors, very low gamma ray flux->>km2 array, large f.o.v • Satellite: too small
HAWC Particle detector $40 M US Wide FOV >90% on time All-sky survey at 10 mCrab/year Moderate angular/energy resolution Major IACT Array $~100 M US narrow FOV 10% on time <1 mCrab point source/50 hours High angular/energy resolution 30 + IACT telescopes? Future -Ray Roadmap (2010+)
Array layout: 2-3 Zones High-energy section ~0.05% area coverage Medium-energy section ~1% area coverage Low-energy section ~10% area coverage FoV increasing to 8-10 degr. in outer sections 70 m 250 m few 1000 m Eth ~ 10-20 GeV Eth ~ 50-100 GeV Eth ~ 1-2 TeV
Option: Mix of telescope types Not to scale !
Point Source Sensitivity of CTA GLAST Crab W. Hofmann CTA Talk (2006) 10% Crab MAGIC 20 wide-angle 10 m telescopes de la Calle Perez, Biller, astro-ph 0602284 30 m stereo telescopes Konopelko Astropart.Phys. 24 (2005) 191 H.E.S.S. Current Simulations 1% Crab
High Density Camera Stack-Up Need a to develop versitile, reliable, cheap camera/readout in Order for IACT array to be feasible.
Analog Ring Sampler (ARS) • Samples PMT signal at 1 GHz • 128 samples ring buffer • Serves to delay signal until trigger decision • High/low gain channels for large dynamic range (> 2000 pe) • Multiplexed ADC to digitize signal; • FPGA • Controls conversion and readout • Optionally sums signals over readout window (16 ns) Photonis PMT XP 2960 8 Dynodes Gain ~2 x 105 Parallel bus for readout, token-passing scheme • Active base • DC-DC converter 0-1500 V • Last 4 dynodes active • HV & current readout • Current limit
Particle Detector Layout HAWC: 5625 or 11250 PMTs (75x75x(1 or 2)) Single layer at 4m depth or 2 layers at Milagro depths Instrumented Area: 90,000m2 PMT spacing: 4.0m Shallow Area: 90,000m2 Deep Area: 90,000m2 miniHAWC: 841 PMTs (29x29) 5.0m spacing Single layer with 4m depth Instrumented Area: 22,500m2 PMT spacing: 5.0m Shallow Area: 22,500m2 Deep Area: 22,500m2 Milagro: 450 PMT (25x18) shallow (1.4m) layer 273 PMT (19x13) deep (5.5m) layer 175 PMT outriggers Instrumented Area: ~40,000m2 PMT spacing: 2.8m Shallow Area: 3500m2 Deep Area: 2200m2 Andy Smith, Santa Fe Workshop 2006
Source Detectability Source Size < Angular resolution = Point Sources: Crab AGN M87 constant
Source Detectability Source Size > Angular Resolution = Diffuse Sources: SNR Tibet-Milagro UID Molecular Cloud n.b. if Source has internal structure you will do better
Diffuse Sources: Galactic Plane Galactic Arm Extended Sources: Molecular clouds SNR, PWN Point Sources: AGN Pulsar Diffuse Sensitivity Next Gen is 1 km2 IACT, 5 deg f.o.v, 1 mCrab/50 hours
CTA HAWC NGA HAWC HAWC VHE Experimental World: 2010
Summary • DM detection probably requires wide fov survey in GeV/TeV energy band comnbined with pointed follow-up • New GeV/TeV sources at wide range of energies, angular scales. • GeV/TeV GRB emission requires all-sky capability • Next generation Instruments require balanced combination of complementary techniques • New Collaborations are being formed at the present time to develop/build next generation Instruments. Chinese participation is highly needed for these major new facilities.
Source Resolvability Source Size > Angular Resolution Just need some factor >1 more S/N to resolve internal source structure
Source Resolvability Source Size < Angular resolution As F increases, tails of Gaussian become detectable->resolve source size
Possible Emission Mechanisms • Inverse Compton scattering • stellar photons • jet synchrotron photons • disk photons • “coronal” photons hadronic origin OR high-mass companion low-mass companion
Hadron Hadron Gamma ray Muon Ring
Point Source All-sky Survey Sensitivity Andy Smith, Santa Fe Workshop 2006