GRB 060418 and GRB 060607A the flares and the spectral lag

1
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
2
the dynamics of the process
3
B210-3 in this source.
Ruffini, Salmonson, Wilson, Xue, AA, 359, 855,
(2000) Ruffini, Bianco, Chardonnet, Fraschetti,
Vitagliano, Xue, Cosmology and Gravitation,
AIP, (2003)
4

• ?E is the internal energy developed in the
  collision with the CBM

the Stefan Boltzmann costant
T temperature of the black body in the comoving
frame
The ratio between effective emitting area and
visible area it takes into account of CBM
filamentary structure (the so called surface
filling factor)
The ratio
is a priori a function of the radial coordinate.
5
Observational features of 060418

• T90 50
• z 1.489
• E? 9 1052,
• FIR,peak 50mJy
• tIR,peak 153s
• E? 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

6

• 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 ?o 400, fully confirming the
  highly relativistic nature of the fireball
• (Molinari et al.2007)

7
Parameters of GRB 060418

• Dyadosphere energy 2.34e55 erg

Lorentz gamma factor 490 higher than the
observational ?o (400) P-GRB laboratory energy
1.22e-02 Edya
Total number of pairs 5.6e59
Plasma temperature 2.53MeV
Dainotti et al. in preparation
8
The global lightcurve of 060418
Dainotti et al. in preparation
9
The Bat lightcurve
P-GRB
Dainotti et al. In preparation
10

• There is no spectral lag between the theoretical
• ? peak and X peak.

They both occur at 26 s
11
The XRT lightcurve
Dainotti et al. in preparation
12
The global lightcurve without a flare
13
The ?-ray lightcurve
14
The X-rays lightcurve
15
GRB 060607A
BAT lc initial spikelike emission 15 s XRT lc
canonical behavior flaring activity Peak of the
IR emission observed by REMIR z 3.082 G0 400
Molinari et al. 2007, AA, 469, L13. Covino et
al., arXiv0710.0727.
16
GRB 060607A

• Etote 2.5 x 1053 erg
• B 3.0 x 10-3
• Ne 2.6 x 1058
• T 1.7 MeV
• ?0 330

LCs well reproduced ?0 compatible with the
estimates
Bernardini et al. in preparation
Molinari et al. 2007, AA, 469, L13. Covino et
al., arXiv0710.0727.
17
Details on the LCs
Prompt emission ltnCBMgt 0.1 /cm3
X-Ray Afterglow
Molinari et al. 2007, AA, 469, L13. Guidorzi,
private communication. Vergani, private
communication.
Bernardini et al. in preparation
18
Still there are some problems
A dn/n 800 ?r 2x1015 cm B dn/n
10 ?r 3x1016 cm
A
B
Failure in reproducing the observed dt/t maybe
full 3d treatment needed!
Bernardini et al. in preparation
19
The CBM behavior
Decreasing particle distribution fragmentation
of fireshell?
Sharp increase of the emitting area?
Dainotti et al., 2007, AA, 471, L29.
20
The comparison between the two sources

• In GRB 060418 the energy and ? are overestimated
• while in the GRB 060607A the value of ? 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.

21
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 .