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GRB 060418 and GRB 060607A the flares and the spectral lag M.G. Dainotti M.G.Bernardini, C.L.Bianco, L. Caito, R. Guida, R.Ruffini
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the dynamics of the process … I: PEM-pulse expansion II: collision with the baryonic remnants III: PEMB-pulse expansion Transparency point in which γasym= 1\B (ABM pulse) Afterglow peak emission Ultrarelativistic regime Relativistic regime
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At transparency point: The percentage of PEMB Pulse internal energy converted into baryonic kinetic energy rises with rising B. Ruffini, Salmonson, Wilson, Xue, A&A, 359, 855, (2000) Ruffini, Bianco, Chardonnet, Fraschetti, Vitagliano, Xue, “Cosmology and Gravitation”, AIP, (2003) B=2*10^-3 in this source.
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ΔE is the internal energy developed in the collision with the CBM The ratio between effective emitting area and visible area :it takes into account of CBM filamentary structure (the so called surface filling factor) the Stefan Boltzmann costant The ratiois a priori a function of the radial coordinate. T: temperature of the black body in the comoving frame
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Observational features of 060418 T 90 = 50 z= 1.489 Eγ= 9* 10^52, F IR,peak= 50mJy t IR,peak =153s Eγ is the isotropic-equivalent prompt gamma-ray energy. For GRB 060418 and 060607A there are measurements of the near infrared afterglows with REM robotic telescope
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we find a constant and low-density medium profile for GRB 060418 and GRB 060607A, which is consistent with the inference from the late afterglow data. The early time afterlow lightcurve carries information on Гo =400, fully confirming the highly relativistic nature of the fireball (Molinari et al.2007)
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Parameters of GRB 060418 Dyadosphere energy: 2.34e55 erg Lorentz gamma factor: 490 higher than the observational Гo (400) P-GRB laboratory energy: 1.22e-02 Edya Total number of pairs: 5.6e59 Plasma temperature: 2.53MeV Dainotti et al. in preparation
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The global lightcurve of 060418 Dainotti et al. in preparation
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The Bat lightcurve P-GRB Dainotti et al. In preparation
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There is no spectral lag between the theoretical γ peak and X peak. They both occur at 26 s
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The XRT lightcurve Dainotti et al. in preparation
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The global lightcurve without a flare
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The γ-ray lightcurve
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The X-rays lightcurve
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BAT lc: initial spikelike emission ~ 15 s XRT lc: canonical behavior + flaring activity Peak of the IR emission observed by REMIR z = 3.082 Γ0 ~ 400 Molinari et al. 2007, A&A, 469, L13. Covino et al., arXiv:0710.0727. GRB 060607A
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Etote±= 2.5 x 10^53 erg B = 3.0 x 10-3 Ne± = 2.6 x 10^58 T = 1.7 MeV γ0 = 330 LCs well reproduced γ0 compatible with the estimates Molinari et al. 2007, A&A, 469, L13. Covino et al., arXiv:0710.0727. Bernardini et al. in preparation GRB 060607A
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Details on the LCs Prompt emission: = 0.1 #/cm3 = 0.1 #/cm3 X-Ray Afterglow: Molinari et al. 2007, A&A, 469, L13. Guidorzi, private communication. Vergani, private communication. Bernardini et al. in preparation
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Still there are some problems A B A: δn/n ~ 800 Δr ~ 2x10^15 cm Δr ~ 2x10^15 cm B: δn/n ~ 10 Δr ~ 3x10^16 cm Δr ~ 3x10^16 cm Failure in reproducing the observed δt/t: maybe full 3d treatment needed! Bernardini et al. in preparation
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The CBM behavior Decreasing particle distribution: fragmentation of fireshell? Sharp increase of the emitting area? Dainotti et al., 2007, A&A, 471, L29.
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The comparison between the two sources In GRB 060418 the energy and Г are overestimated while in the GRB 060607A the value of Г is understimated. The densities of GRB 060607 are in good agreement with the observations While in 060418 the density mask is still incomplete and it is not constant.
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It is still a preliminary result! There are problems on the energetics much higher than the experimantal probably due to a misleading individuation of the P- GRB.
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