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UHECR source searches and magnetic fields. Dmitri Semikoz APC , Paris. based on works in in collaboration with X.Derkx, K.Dolag, A.Elyiv, G.Gianciti, M.Kachelries and A.Neronov. Overview:.
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UHECR source searches and magnetic fields Dmitri Semikoz APC , Paris based on works in in collaboration with X.Derkx, K.Dolag, A.Elyiv, G.Gianciti, M.Kachelries and A.Neronov
Overview: • Search for signal of point-like sources distorted by galactic magnetic field • Sources located in the magnetized regions • Extragalactic fields: models and measurements • Conclusions
UHECR propagation in Milky Way • Deflection angle ~ 1-2 degrees at 1020eV for protons • Astronomy by hadronic particles?
Uncertainty of GMF models • From M.Kachelriess P.Serpico and M.Teshima, astro-ph/0510444 • Protons with energy 4*1019 eV deflection in galactic magnetic field. TT model HMR model PS model
Signal of individual source on sky G.Giacinti, X.Derkx and D.S.
Deflections by EGMF By K.Dolag, D.Grasso, V.Springel, and I.Tkachev
Signal from M87 at different energies K.Dolag, M.Kachelriess and D.S., arXiv:0809.5055
Calculation of probability • Propagate UHECR 50000, 100000, 150000, 200000 etc. • For given angle fit to infinit number of UHECR • Take results at several angles • Extrapolation to zero angle
Production of secondary TeV photons: distances A.Neronov and D.S., astro-ph/0604607
Maximal magnetic field • Maximal magnetic field can be found from the condition that highest energy photons which still can reach detector are not deflected outside of jet.
Minimal magnetic field • Minimal magnetic field can be found from the condition that lowest energy photons can not be resolved from point source flux
Extended emission around Mkn 180 K.Dolag, M.Kachelriess, S.Ostapchenko and R.Tomas , astro-ph/ 0903.2842
Extended emission around Mkn 180 K.Dolag, M.Kachelriess, S.Ostapchenko and R.Tomas , astro-ph/ 0903.2842
Gamma–ray cascade in EGMF A. Elyiv, A.Neronov and D.Semikoz, astro-ph/ 0903.3649
Gamma–ray cascade in EGMF with B=1.e-15-1.e-14 G A. Elyiv, A.Neronov and D.Semikoz, astro-ph/ 0903.3649
Gamma–ray cascade in EGMF A. Elyiv, A.Neronov and D.Semikoz, astro-ph/ 0903.3649
Gamma–ray cascade in EGMF A. Elyiv, A.Neronov and D.Semikoz, astro-ph/ 0903.3649
Conclusions • Search of individual UHECR sources can be done if regular component of galactic field dominates deflections. Turbulent field strongly reduce signal to noise ratio. • Sources in magnetized regions like M87 in Virgo can give complicated signals due to magnetic lensing. • Magnetic fields in voids of LSS can be measured by TeV telescopes