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MAGIC & The Speed of Light

MAGIC & The Speed of Light. Nick E. Mavromatos King’s College London HSSHEP 2008 Workshop, Ancient Olympia, Greece, April 16-19 2008. OUTLINE I. High-Energy Gamma Ray Astrophysics as a probe for New Physics

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MAGIC & The Speed of Light

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  1. MAGIC & The Speed of Light Nick E. Mavromatos King’s College London HSSHEP 2008 Workshop, Ancient Olympia, Greece, April 16-19 2008

  2. OUTLINEI • High-Energy Gamma Ray Astrophysics as a probe for New Physics • The MAGIC results:non-simultaneous arrival of TeV photons from AGN Mk 501, more energetic photons arrive later… • Possible Interpretations: (i) Astro-Physics at source: synchrotron radiation, Compton scattering produce delays at emission: Non conclusive (ii) Exotic Interpretation: Quantum Gravity (QG) propagation effects (?): QG as a medium with refractive index, Modified Dispersion Relations for matter probes with Linear QG scale suppression (LMDR) • Check on other tests on (LMDR) modified dispersion relations:Electrons: Synchrotron Radiation from Crab Nebula Photons: Birefringence constraints for LMDR MAGIC & The Speed of Light N.E. Mavromatos

  3. OUTLINEII • Stringy Models of space time foam (SMSTF) : Non-universal action of ``gravity foam’’ on matter probes: Electrons (and in general charged particles) transparent, Photons (and neutral particles) feel the foam medium effects • String Uncertainties, Non-commutative geometry atstring scales& the MAGIC result :a uniquely stringy effect ? …. Compatible with other tests constraining LMDR • Other consequences of the SMSTF:CPT Violation (ill-definition) due to decoherenceand unique effects (?) in entangled states of meson factories • Outlook:NEED TO CONFIRM MAGIC effect by H.E.S.S. and other experiments, further tests using High-Energy Neutrino astrophysics MAGIC & The Speed of Light N.E. Mavromatos

  4. OUTLINEII • Stringy Models of space time foam (SMSTF) : Non-universal action of ``gravity foam’’ on matter probes: Electrons (and in general charged particles) transparent, Photons (and neutral particles) feel the foam medium effects Sub-luminal Refractive index in vacuo, No Birefringence • String Uncertainties, Non-commutative geometry atstring scales& the MAGIC result :a uniquely stringy effect ? …. Compatible with other tests constraining LMDR • Other consequences of the SMSTF:CPT Violation (ill-definition) due to decoherenceand unique effects (?) in entangled states of meson factories • Outlook:NEED TO CONFIRM MAGIC effect by H.E.S.S. and other experiments, further tests using High-Energy Neutrino astrophysics MAGIC & The Speed of Light N.E. Mavromatos

  5. OUTLINEII • Stringy Models of space time foam (SMSTF) : Non-universal action of ``gravity foam’’ on matter probes: Electrons (and in general charged particles) transparent, Photons (and neutral particles) feel the foam medium effects Sub-luminal Refractive index in vacuo, No Birefringence • String Uncertainties, Non-commutative geometry atstring scales& the MAGIC result :a uniquely stringy effect ? …. Compatible with other tests constraining LMDR • Other consequences of the SMSTF:CPT Violation (ill-definition) due to decoherenceand unique effects (?) in entangled states of meson factories • Outlook:NEED TO CONFIRM MAGIC effect by H.E.S.S. and other experiments, further tests using High-Energy Neutrino astrophysics MAGIC & The Speed of Light N.E. Mavromatos

  6. A flow of high energy particles reaches Earth: Cosmic Rays 90% protons, < 10% He nuclei, < 1% heavier ionised elements , < 1% electrons 0,1 – 1 % PHOTONS > MeV energies (Gamma Rays) High Energy Gamma Ray Astrophysics MAGIC & The Speed of Light N.E. Mavromatos

  7. A flow of high energy particles reaches Earth: Cosmic Rays 90% protons, < 10% He nuclei, < 1% heavier ionised elements , < 1% electrons 0,1 – 1 % PHOTONS > MeV energies (Gamma Rays) High Energy Gamma Ray Astrophysics MAGIC & The Speed of Light N.E. Mavromatos

  8. A flow of high energy particles reaches Earth: Cosmic Rays 90% protons, < 10% He nuclei, < 1% heavier ionised elements , < 1% electrons 0,1 – 1 % PHOTONS > MeV energies (Gamma Rays) High Energy Gamma Ray Astrophysics Gamma Rays: most interesting part of spectrum from Astrophysical Sources: e.g. from Active Galactic Nuclei (AGN) : > 20 MeV MAGIC & The Speed of Light N.E. Mavromatos

  9. A flow of high energy particles reaches Earth: Cosmic Rays 90% protons, < 10% He nuclei, < 1% heavier ionised elements , < 1% electrons 0,1 – 1 % PHOTONS > MeV energies (Gamma Rays) High Energy Gamma Ray Astrophysics • Classification of High-Energy Gamma Rays : High Energy: 20 MeV -100 GeV Very High Energy: 100 GeV-30 TeV Ultra High Energy: 30 TeV – 30 PeV Extremely High Energy : 30 PeV - ? Gamma Rays: most interesting part of spectrum from Astrophysical Sources: e.g. from Active Galactic Nuclei (AGN) : > 20 MeV MAGIC & The Speed of Light N.E. Mavromatos

  10. PRODUCTION OF HIGH ENERGY GAMMA RAYS • Photons from conversion of gravitational Energy (AGN) • From self-annihilation of Dark Matter • Decays of exotic massive particle in very Early Universe MAGIC & The Speed of Light N.E. Mavromatos

  11. PRODUCTION OF HIGH ENERGY GAMMA RAYS • Photons from conversion of gravitational Energy (AGN) • From self-annihilation of Dark Matter • Decays of exotic massive particle in very Early Universe MAGIC & The Speed of Light N.E. Mavromatos

  12. AGN High Energy Gamma Rays High-Energy Photons from Gravitational Energy Conversion, released by collapses towards a central massive object (black hole); angular momentum implies accretion disk, and jets outflowing the accretion plane… Most popular Interpretation is Self-Synchrotron-Compton (SSC): Time-varying populations of Ultrarelativistic electrons accelerated in strong magnetic fields Synchrotron Radiation generating Inverse Compton Emission (100 MeV-100 GeV) from soft photons scattered off energetic electrons. Compton components peak at TeV energies. MAGIC & The Speed of Light N.E. Mavromatos

  13. Sy IC log(energy density) leptonic acceleration Synchrotron  (eV-keV) e- (TeV) B  (TeV) Inverse Compton log(E) eVkeVMeVGeVTeV  (eV) AGN High Energy Gamma Rays - electron accelerators: synchrotron: e B -> e gamma + inverse Compton: e gamma -> gamma e MAGIC & The Speed of Light N.E. Mavromatos

  14. Gamma Ray Detection Detection by Cherenkov Telescopes • Do not detect the Gamma Ray directly but the Cherenkov radiation it produces entering the atmosphere…. MAGIC & The Speed of Light N.E. Mavromatos

  15. Electromagnetic Shower Hadronic Shower Cherenkov Effect MAGIC & The Speed of Light N.E. Mavromatos

  16. Detection of TeV gamma rays using Cherenkovtelescopes Gamma- ray Particle shower ~ 10 km ~ 1o Cherenkov light ~ 120 m Observation Technique MAGIC & The Speed of Light N.E. Mavromatos

  17. VHE Experimental World Today TIBET MILAGRO MAGIC STACEE TACTIC CANGAROO HESS TIBET ARRAY ARGO-YBJ MILAGRO STACEE CACTUS TACTIC PACT GRAPES MAGIC & The Speed of Light N.E. Mavromatos M. MARTINEZ

  18. VHE Experimental World Today TIBET MILAGRO MAGIC STACEE TACTIC CANGAROO HESS TIBET ARRAY ARGO-YBJ MILAGRO STACEE CACTUS TACTIC PACT Canary Islands GRAPES MAGIC & The Speed of Light N.E. Mavromatos M. MARTINEZ

  19. The MAGIC Collaboration (Major Atmospheric Gamma-ray ImagingCherenkov Telescope ) Observation of Flares from AGN Mk 501 Red-shift: z=0.034 MAGIC & The Speed of Light N.E. Mavromatos

  20. The MAGIC ``Effect’’ MAGIC & The Speed of Light N.E. Mavromatos

  21. Possible Interpetations • Delays of more energetic photons are a result of AGN source Physics (SSC mechanism) MAGIC Coll. ApJ 669, 862 (2007) : SSC I Bednarek & Wagner arXive:0804.0619 : SSCII • Delays of more energetic photons occur in propagation due to new fundamental Physics (e.g. refractive index in vacuo due to Quantum Gravity space-time Foam Effects…) MAGIC Coll & Ellis, NM, Nanopoulos, Sakharov, Sarkisyan [arXive:0708.2889] (individual photon analysis) MAGIC & The Speed of Light N.E. Mavromatos

  22. SSC as explanation of the MAGIC Effect • Classical SSC model: emission region moves along the jet with constant Lorentz factors . In other AGN (e.g.; Crab Nebula), such factors are of order 10 – 20 . However, to account for the 4 ± 1 minute delay observed in MAGIC requires Lorentz factors four orders of magnitude higher. • Modify SSC model :(i) assume gradual acceleration of relativistic electrons inside blob (SSC I) (ii) assume the blob captured in inner part of the jet during its acceleration phase (SSC II): lower-energy part of flare close to base of the jet, lower Lorentz factor, higher-energy at larger distances from jet base, higher Lorentz factor. Time-delay in SSC II inversely proportional to γ-ray Energies • SITUATION NON CONCLUSIVE: DOES FLARE PHYSICS DEPEND ON INDIVIDUAL FLARES (SSC I) ? MATTER OF LUCK TO HAVE OBSERVED BLOB IN ITS ACCELERATION PHASE IN Mk501 (SSC II) ? MAGIC & The Speed of Light N.E. Mavromatos

  23. SSC as explanation of the MAGIC Effect • Classical SSC model: emission region moves along the jet with constant Lorentz factors . In other AGN (e.g.; Crab Nebula), such factors are of order 10 – 20 . However, to account for the 4 ± 1 minute delay observed in MAGIC requires Lorentz factors four orders of magnitude higher. • Modify SSC model :(i) assume gradual acceleration of relativistic electrons inside blob (SSC I) (ii) assume the blob captured in inner part of the jet during its acceleration phase (SSC II): lower-energy part of flare close to base of the jet, lower Lorentz factor, higher-energy at larger distances from jet base, higher Lorentz factor. Time-delay in SSC II inversely proportional to γ-ray Energies • SITUATION NON CONCLUSIVE: DOES FLARE PHYSICS DEPEND ON INDIVIDUAL FLARES (SSC I) ? MATTER OF LUCK TO HAVE OBSERVED BLOB IN ITS ACCELERATION PHASE IN Mk501 (SSC II) ? MAGIC & The Speed of Light N.E. Mavromatos

  24. SSC as explanation of the MAGIC Effect • Classical SSC model: emission region moves along the jet with constant Lorentz factors . In other AGN (e.g.; Crab Nebula), such factors are of order 10 – 20 . However, to account for the 4 ± 1 minute delay observed in MAGIC requires Lorentz factors four orders of magnitude higher. • Modify SSC model :(i) assume gradual acceleration of relativistic electrons inside blob (SSC I) (ii) assume the blob captured in inner part of the jet during its acceleration phase (SSC II): lower-energy part of flare close to base of the jet, lower Lorentz factor, higher-energy at larger distances from jet base, higher Lorentz factor. Time-delay in SSC II inversely proportional to γ-ray Energies • SITUATION NON CONCLUSIVE: DOES FLARE PHYSICS DEPEND ON INDIVIDUAL FLARES (SSC I) ? MATTER OF LUCK TO HAVE OBSERVED BLOB IN ITS ACCELERATION PHASE IN Mk501 (SSC II) ? MAGIC & The Speed of Light N.E. Mavromatos

  25. Quantum Gravity as a dispersive medium (space-time foam) , modified dispersion relations (MDR) for matter, radiation Phenomenological Models of MDR Gonzalez-Mestres, Amelino-Camelia, Ellis, NM, Nanopoulos, Sarkar Stochastically fluctuating space time backgrounds Ford, Yu , Sarben Sarkar, NM… String & Brane-inspired Models Ellis, NM, Nanopoulos, Szabo, Sakharov, Farakos, Mitsou, … Loop Quantum Gravity (?) Gambini, Pullin, Urrutia, … Deformed Special Relativity Models (unclear if there is a consistent quantum version) Amelino-Camelia, Magueijo, Smolin, Kowalski- Glikman … New fundamental Physics Interpretation MAGIC & The Speed of Light N.E. Mavromatos

  26. Quantum Gravity as a dispersive medium (space-time foam) , modified dispersion relations (MDR) for matter, radiation Phenomenological Models of MDR Gonzalez-Mestres, Amelino-Camelia, Ellis, NM, Nanopoulos, Sarkar Stochastically fluctuating space time backgrounds Ford, Yu , Sarben Sarkar, NM… String & Brane-inspired Models Ellis, NM, Nanopoulos, Szabo, Sakharov, Farakos, Mitsou, … Loop Quantum Gravity (?) Gambini, Pullin, Urrutia, … Deformed Special Relativity Models (unclear if there is a consistent quantum version) Amelino-Camelia, Magueijo, Smolin, Kowalski- Glikman … New fundamental Physics Interpretation Complex refractive index MAGIC & The Speed of Light N.E. Mavromatos

  27. Quantum Gravity as a dispersive medium (space-time foam) , modified dispersion relations (MDR) for matter, radiation Phenomenological Models of MDR Gonzalez-Mestres, Amelino-Camelia, Ellis, NM, Nanopoulos, Sarkar Stochastically fluctuating space time backgrounds Ford, Yu , Sarben Sarkar, NM… String & Brane-inspired Models Ellis, NM, Nanopoulos, Szabo, Sakharov, Farakos, Mitsou, … Loop Quantum Gravity (?) Gambini, Pullin, Urrutia, … Deformed Special Relativity Models (unclear if there is a consistent quantum version) Amelino-Camelia, Magueijo, Smolin, Kowalski- Glikman … New fundamental Physics Interpretation Complex refractive index MAGIC & The Speed of Light N.E. Mavromatos

  28. Quantum-Gravity Induced Modified Dispersion for Photons Modified dispersion due to QG induced space-time (metric) distortions (c=1 units): MAGIC & The Speed of Light N.E. Mavromatos

  29. Quantum-Gravity Induced Modified Dispersion for Photons Modified dispersion due to QG induced space-time (metric) distortions (c=1 units): MAGIC & The Speed of Light N.E. Mavromatos

  30. Quantum-Gravity Induced Modified Dispersion for Photons Modified dispersion due to QG induced space-time (metric) distortions (c=1 units): MAGIC & The Speed of Light N.E. Mavromatos

  31. Try to use the FULL gamma-ray information to study the Eg v.s. tg correlation. Low statistics (as compared with typical GRBs) need for development of new analysis approaches: 1) Maximize Energy Cost Function (ECF) – Exploit individual photon study possibility : reproduce peak of flare by using modified dispersion relations for individual photons (both linear and quadratic in MQG) MAGIC Coll. & Ellis, N.M. Sakharov, Sarkisyan, arXive: 07082889 2) Fit likelihood function – using different shapes of flare and energy spectra M.Martinez, M.Errando, arXive: 08032120 Fitting the MAGIC Effect MAGIC & The Speed of Light N.E. Mavromatos

  32. Fitting the MAGIC Effect • The 4 ± 1 minute delay of most energetic photons observed in the MAGIC Telescope can be reproduced by a subluminal refractive index (propagation effect), either scaling linearly or quadratic with the quantum-gravity scale… MAGIC & The Speed of Light N.E. Mavromatos

  33. ENERGY COST FUNCTIONAL (ECF) METHEOD arXive: 07082889 MAGIC & The Speed of Light N.E. Mavromatos

  34. LIKELIHOOD METHOD arXive: 07082889 MAGIC & The Speed of Light N.E. Mavromatos

  35. MAGIC Results (ECF Method): Quadratic Linear 95% CL MAGIC & The Speed of Light N.E. Mavromatos

  36. MDR for other matter probes Massive Probes (e.g. electrons): Constraints from Crab Nebula via Synchrotron Radiation Jacobson, Liberatti, Mattingly, Ellis, NM, Sakharov Electron moving in magnetic field H emits discrete frequency spectrum with a maximum at critical frequency: R=orbit radius, c(ωc)=photon group velocity, v(E)=electron group velocity δ(E) = angle for forward radiation pattern Experimental measurement of ωc (Crab Nebula) yields For MQG = MQG1 (MAGIC)~ 1018GeV that α > 1.74 MAGIC & The Speed of Light N.E. Mavromatos

  37. MDR for other matter probes Massive Probes (e.g. electrons): Constraints from Crab Nebula via Synchrotron Radiation Jacobson, Liberati, Mattingly, Ellis, NM, Sakharov Electron moving in magnetic field H emits discrete frequency spectrum with a maximum at critical frequency: R=orbit radius, c(ωc)=photon group velocity, v(E)=electron group velocity δ(E) = angle for forward radiation pattern WHAT ABOUT PHOTONS & THE MAGIC RESULT? Experimental measurement of ωc (Crab Nebula) yields For MQG = MQG1 (MAGIC)~ 1018GeV that α > 1.74 MAGIC & The Speed of Light N.E. Mavromatos

  38. Birefringence Constraints on photons MDR • If MDR for probes stem from Local Effective Lagrangians (LEL): Maccione et al., arXive0707.2673 Photons :Electrons: Myers- Pospelov QED Difference in polarization angle over cosmological distance d: ± signs indicate left/right movers and for Circularly polarized photons imply rotation of linear polarization angle (BIREFRINGENCE). UV radiation from Galaxies: For FromGRB polarization MAGIC & The Speed of Light N.E. Mavromatos

  39. Birefringence Constraints on photons MDR • If MDR for probes stem from Local Effective Lagrangians (LEL): Maccione et al., arXive0707.2673 Photons :Electrons: Myers- Pospelov QED Difference in polarization angle over cosmological distance d: ± signs indicate left/right movers and for Circularly polarized photons imply rotation of linear polarization angle (BIREFRINGENCE). UV radiation from Galaxies: For FromGRB polarization MAGIC EFFECT due to QG ruled out ? MAGIC & The Speed of Light N.E. Mavromatos

  40. A Stringy Model of Space -Time Foam Ellis, NM, Nanopoulos Open strings on D3-brane world represent electrically neutral matter or radiation, interacting via splitting/capture with D-particles (electric charge conservation) . D-particle foam medium transparent to (charged) Electrons no modified dispersion for them Photons or electrically neutral probes feel the effects of D-particle foam Modified Dispersion for them…. MAGIC & The Speed of Light N.E. Mavromatos

  41. A Stringy Model of Space -Time Foam Ellis, NM, Nanopoulos Open strings on D3-brane world represent electrically neutral matter or radiation, interacting via splitting/capture with D-particles (electric charge conservation) . D-particle foam medium transparent to (charged) Electrons no modified dispersion for them Photons or electrically neutral probes feel the effects of D-particle foam Modified Dispersion for them…. NON-UNIVERSAL ACTION OF D-PARTICLE FOAM ON MATTER & RADIATION MAGIC & The Speed of Light N.E. Mavromatos

  42. A Stringy Model of Space -Time Foam Ellis, NM, Nanopoulos Open strings on D3-brane world represent electrically neutral matter or radiation, interacting via splitting/capture with D-particles (electric charge conservation) . D-particle foam medium transparent to (charged) Electrons no modified dispersion for them Photons or electrically neutral probes feel the effects of D-particle foam Modified Dispersion for them…. NON-UNIVERSAL ACTION OF D-PARTICLE FOAM ON MATTER & RADIATION MAGIC & The Speed of Light N.E. Mavromatos

  43. Stringy Uncertainties & the Capture Process During Capture: intermediate String stretching between D-particle and D3-brane is Created. It acquires N internal Oscillator excitations & Grows in size & oscillates from Zero to a maximum length by absorbing incident photon Energy p0 : Minimise right-hand-size w.r.t. L. End of intermediate string on D3-brane Moves with speed of light in vacuo c=1 Hence TIME DELAY(causality) during Capture: DELAY IS INDEPENDENT OF PHOTON POLARIZATION, HENCE NO BIREFRINGENCE…. MAGIC & The Speed of Light N.E. Mavromatos

  44. Stringy Uncertainties & the MAGIC Effect • D-foam: transparent to electrons • D-foam captures photons & re-emits them • Time Delay (Causal) in each Capture: • Independent of photon polarization (no Birefringence) • Total Delay from emission of photons till observation over a distance D (assume n* defects per string length): Effectively modified Dispersion relation for photons due to induced metric distortion G0i ~ p0 REPRODUCE 4±1 MINUTE DELAY OF MAGIC from Mk501 (redshift z=0.034) For n* =O(1) & Ms ~ 1018 GeV, consistently with Crab Nebula & other Astrophysical constraints on modified dispersion relations…… MAGIC & The Speed of Light N.E. Mavromatos

  45. Other Consequences of D-particle Foam • Low-energy CPT Violation & Decoherence from stochastic fluctuations of D-particle defects: Capture/re-emission process for neutral probes implies recoil of D-particle defect, momentum-direction-dependent induced metricsG0i ~ Δki ~ ki ~ p0 (Logarithmic Conformal Field Theory of recoil/capture on world-sheet of string model) Kogan,NM,Wheater,Szabo, Ellis, Nanopoulos • CPT Operator ill-defined, unique consequences in modifications of EPR correlations of entangled states of neutral mesons in meson factories (Φ-, B-factories) Bernabeu, NM, Papavassiliou,Nebot, Alvarez, Sarben Sarkar Estimates of such D-particle foam effects in neutral mesons complicated due to strong QCD effects present in such composite neutral particles MAGIC & The Speed of Light N.E. Mavromatos

  46. Other Consequences of D-particle Foam • If CPT Operator well-defined as operator, even if CPT is broken in the Hamiltonian… (e.g. Lorentz violating models) Φ KSKL KSKL MAGIC & The Speed of Light N.E. Mavromatos

  47. EPR Modifications & D-particle Foam • If CPT Operator ill-defined, unique consequences in modifications of EPR correlations of entangled states of neutral mesons in meson factories (Φ-, B-factories) Bernabeu, NM, Papavassiliou,Nebot, Alvarez, Sarben Sarkar Φ KSKL KSKL KSKL IF CPT ILL-DEFINED (e.g. D-particle Foam) Induced metric due to capture/recoil, stochastic fluctuations, Decoherence MAGIC & The Speed of Light N.E. Mavromatos

  48. EPR Modifications & D-particle Foam • CPT Operator ill-defined, unique consequences in modifications of EPR correlations of entangled states of neutral mesons in meson factories (Φ-, B-factories) Bernabeu, NM, Papavassiliou,Nebot, Alvarez, Sarben Sarkar Φ KSKL KSKL KSKL KSKS , KLKL KSKS , KLKL IF CPT ILL-DEFINED (e.g. D-particle Foam) Induced metric due to capture/recoil, stochastic fluctuations, Decoherence Estimates of such D-particle foam effects in neutral mesons complicated due to strong QCD effects present in such composite neutral particles MAGIC & The Speed of Light N.E. Mavromatos

  49. Neutral mesons no longer indistinguishable particles, initial entangled state: Φ KSKL KSKL KSKS , KLKL KSKS , KLKL IF CPT ILL-DEFINED (e.g. D-particle Foam) If QCD effects, sub-structure in neutral mesons ignored, and D-foam acts as if they were structureless particles, then for MQG ~ 1018 GeV (MAGIC) the estimate for ω: | ω | ~ 10-4 |ζ|, for 1 > |ζ| > 10-2 (natural) Not far from sensitivity of upgraded meson factories ( e.g. DAFNE2) MAGIC & The Speed of Light N.E. Mavromatos

  50. Neutral mesons no longer indistinguishable particles, initial entangled state: Φ KSKL KSKL KSKS , KLKL KSKS , KLKL IF CPT ILL-DEFINED (e.g. D-particle Foam) If QCD effects, sub-structure in neutral mesons ignored, and D-foam acts as if they were structureless particles, then for MQG ~ 1018 GeV (MAGIC) the estimate for ω: | ω | ~ 10-4 |ζ|, for 1 > |ζ| > 10-2 (natural) Not far from sensitivity of upgraded meson factories ( e.g. DAFNE2) MAGIC & The Speed of Light N.E. Mavromatos

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