Thermal Emission in Gamma-Ray Burst
Afterglows
D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Badjin, Blinnikov & Postnov, MNRAS 432 (2013) 2454

Sternberg Astronomical Institute of Moscow State University,
Alikhanov Institute for Theoretical and Experimental Physics,
Moscow, Russia
Supernovae and Gamma-Ray Bursts Workshop
Kyoto, November 5th , 2013

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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst Afterglows

Outline

INTRODUCTION

Brief introduction
The model and modelingResults of simulations
Test against observations

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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst Afterglows

INTRODUCTION

Why Thermal Emission in Afterglows?
General considerations: a lot of matter(previously ejected by the massive progenitorstar)+ a lot of energy (1051 − 1053 erg)

⇒ Thermal Emission (TE). Analogy withsupernovae.

Observational evidence:well known SN-bumps (the most obvious signature of TE in
GRBs,

Woosley & Bloom 2006, Cano et al. 2011 )more earlier optical light curve irregularities (deviations from a
power law fading) sometimes observed in afterglows. At least
some of them may have thermal nature.
`Thermal trend' in prompt emission studies

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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst Afterglows

INTRODUCTION

Why Thermal Emission in Afterglows?
General considerations: a lot of matter(previously ejected by the massive progenitorstar)+ a lot of energy (1051 − 1053 erg)

⇒ Thermal Emission (TE). Analogy withsupernovae.

Observational evidence:well known SN-bumps (the most obvious signature of TE in
GRBs,

Woosley & Bloom 2006, Cano et al. 2011 )more earlier optical light curve irregularities (deviations from a
power law fading) sometimes observed in afterglows. At least
some of them may have thermal nature.
`Thermal trend' in prompt emission studies

3/26

D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst Afterglows

INTRODUCTION

Why Thermal Emission in Afterglows?
General considerations: a lot of matter(previously ejected by the massive progenitorstar)+ a lot of energy (1051 − 1053 erg)

⇒ Thermal Emission (TE). Analogy withsupernovae.

Observational evidence:well known SN-bumps (the most obvious signature of TE in
GRBs,

Woosley & Bloom 2006, Cano et al. 2011 )more earlier optical light curve irregularities (deviations from a
power law fading) sometimes observed in afterglows. At least
some of them may have thermal nature.
`Thermal trend' in prompt emission studies

3/26

D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst Afterglows

INTRODUCTION

Picture of a Model

A massive star → Pulsations or instabilities → 1-st ejection →2-nd ejection, ejected masses collide and form structures (e.g. denseshells,Ofek et.al, 2013 ). → ... → ~ GRB, the shell is illuminated byprompt emission and then the relativistic ejecta runs into it.

gamma-rays

Eiso=4.5·1053 erg
thermal emission

EjectaR=1016 cm

h=5·1013 cm, n~1010 cm-3

The shell gains energy and should radiate it.
Essentials ...
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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst AfterglowsModeling with the STELLA CodeModeling with the STELLA code

The STELLA code, originally developed for supernova light curve
simulations, (Blinnikov et al., 1998 )multigroup time dependent radiation hydrodynamics
Non-relativistic (O(v/c)), spherically symmetric,
Lagrangean coordinates, staggered mesh.
Full implicit time-dependent predictor-corrector solver for stiODE systems, modied Gear method (Brayton, Gustavson,
Hatchel, 1972 ), exible dynamic step and error control.

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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst AfterglowsModeling with the STELLA CodeInitial Model

A continuous spherical shell discretized with 100 concentric

10 cm−3 ) andmass coordinate layers. Particle density (n ∼ 10

16 cm, δr/r = 0.005).
extents (r ∼ 10
Resembles

Woosley, Blinnikov & Heger (2007) pre-supernova

shell. Abundances were taken from that paper.
Also to ensuresignicant intercepted energy;
no possibility for relativistic motions to appear
not great Thomson optical thickness (τT ∼ 1)
Only radial structure is available, but is unimportant because ofsmall relative thickness.
Dierent models had been simulated, but such a `wall' displays
the most pronounced features.

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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst AfterglowsModeling with the STELLA CodeInitial Model

A continuous spherical shell discretized with 100 concentric

10 cm−3 ) andmass coordinate layers. Particle density (n ∼ 10

16 cm, δr/r = 0.005).
extents (r ∼ 10
Resembles

Woosley, Blinnikov & Heger (2007) pre-supernova

shell. Abundances were taken from that paper.
Also to ensuresignicant intercepted energy;
no possibility for relativistic motions to appear
not great Thomson optical thickness (τT ∼ 1)
Only radial structure is available, but is unimportant because ofsmall relative thickness.
Dierent models had been simulated, but such a `wall' displays
the most pronounced features.

6/26

D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst AfterglowsModeling with the STELLA CodeInitial Model

A continuous spherical shell discretized with 100 concentric

10 cm−3 ) andmass coordinate layers. Particle density (n ∼ 10

16 cm, δr/r = 0.005).
extents (r ∼ 10
Resembles

Woosley, Blinnikov & Heger (2007) pre-supernova

shell. Abundances were taken from that paper.
Also to ensuresignicant intercepted energy;
no possibility for relativistic motions to appear
not great Thomson optical thickness (τT ∼ 1)
Only radial structure is available, but is unimportant because ofsmall relative thickness.
Dierent models had been simulated, but such a `wall' displays
the most pronounced features.

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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst AfterglowsModeling with the STELLA Code

Basic Equations
Radiation:∂(ur2 )∂c ∂2 ∂t Jν = c(ην − χab Jν ) − r2 ∂r Jν − r2 ∂r (r Hν )+




2)


∂

f J ),+ 1 − ν13 ∂ν(ν 4 ...) ( ur (3fE − 1)Jν − ∂(urr2 ∂r E ν





∂
2 ∂(ur)∂t Hν = −c(χab + χsc )Hν − r ∂r Hν −−c ∂ (f J ) − c (3f − 1)J − Ḣ
∂r

E

ν

r

E

ν

ν,dif f
Hydrodynamics:





∂r
1
∂r


∂t = u,∂m = 4πr2 ρ ,
R∞ χab +χsc∂u

2 ∂(p+qvis ) − Gm + 4π=
−4πrHν dν + amix
2

∂t
∂m
c
ρ
r


0

 

∞

 ∂e  ∂T =  + 4π R χab (J − B )dν − 4π ∂(ur2 ) (T ∂p + q)νν ∂T ρ ∂t
ρ
∂m
∂T
0

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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

ρThermal Emission in Gamma-Ray Burst AfterglowsModeling with the STELLA CodeNew!

Prompt Emission

3 FRED pulses × 1.5 s, total duration 15 s, isotropic

Lpeak = 3 · 1053 erg/s, broken power-law spectrum(1 keV30 MeV, α = 0.9, β = 2.001, E0 = 300 keV), 100◦
energies. Assumed collimation θjet = 10

Rapidly varying external force:R∞ χab +χsc∂u
4π=
Hγ dεγ + ...,
∂t
c
ρ
0
 ∂T
R∞ χab +ηC χsc∂e4π
Jγ dεγ + ...
∂T ρ ∂t = c
ρ
0
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D.A. Badjin, S.I. Blinnikov, K.A. Postnov−

Thermal Emission in Gamma-Ray Burst AfterglowsModeling with the STELLA CodeNew!

Prompt Emission

Rapidly varying external force:R∞ χab +χsc∂u
4π=
Hγ dεγ + ...,
∂t
c
ρ
0
 ∂T
R∞ χab +ηC χsc∂e4π
Jγ dεγ + ...
∂T ρ ∂t = cρ0χab , χsc  photoionization, Compton scattering on b and f e−
One scattering approximation (accuracy ∼ 10% in heatingR

power), Jγ ≈ Hγ =8/26

Lγ e− χ(r,t)ds
16π 2 r2

D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst AfterglowsModeling with the STELLA CodeNew!

State of Matter∂nzi∂t |ρ = R(ne )nzi ,15 elements ⇒≈ 200 ion species → nzi , ne , p, ∂p, e, ∂e, χ,Time dependent ionization kinetics... within ctγ = 15 light seconds behind the γ -ray front →Smooth transition to the Boltzmann-Saha solution

12 , i.e.

The transition time scale should satisfy ne t ∼ 10

10 − 100 s.
12 /n , though lackinge

One temperature uid ≈ valid for t > 10−
in superthermal e .

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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst AfterglowsModeling with the STELLA CodeNew!

State of Matter∂nzi∂t |ρ = R(ne )nzi ,15 elements ⇒≈ 200 ion species → nzi , ne , p, ∂p, e, ∂e, χ,Time dependent ionization kinetics... within ctγ = 15 light seconds behind the γ -ray front →Smooth transition to the Boltzmann-Saha solution

12 , i.e.

The transition time scale should satisfy ne t ∼ 10

10 − 100 s.
12 /n , though lackinge

One temperature uid ≈ valid for t > 10−
in superthermal e .

9/26

D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst AfterglowsModeling with the STELLA CodeNew!

State of Matter∂nzi∂t |ρ = R(ne )nzi ,15 elements ⇒≈ 200 ion species → nzi , ne , p, ∂p, e, ∂e, χ,Time dependent ionization kinetics... within ctγ = 15 light seconds behind the γ -ray front →Smooth transition to the Boltzmann-Saha solution

12 , i.e.

The transition time scale should satisfy ne t ∼ 10

10 − 100 s.
12 /n , though lackinge

One temperature uid ≈ valid for t > 10−
in superthermal e .

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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst AfterglowsModeling with the STELLA CodeNew!

The Ejecta

Immediate deceleration

Ekk
6 Mdec < cE
2 Γ2 << Mshell ⇒c2 Γ

thermalization.

53 erg is deposited into

Thermal energy Ek = Eiso,γ = 4.5 · 10

the innermost zone over δRz /c ≈ 17 s time scale. A `Thermal
Bomb' is triggered ∆tγ−ej ∼R≈ 200 s for Γ = 30.
2cΓ2A clumpy structure is necessary to let the long term
synchrotron afterglow to be emitted.

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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst AfterglowsModeling with the STELLA CodeNew!

The Ejecta

Immediate deceleration

Ekk
6 Mdec < cE
2 Γ2 << Mshell ⇒c2 Γ

thermalization.

53 erg is deposited into

Thermal energy Ek = Eiso,γ = 4.5 · 10

the innermost zone over δRz /c ≈ 17 s time scale. A `Thermal
Bomb' is triggered ∆tγ−ej ∼R≈ 200 s for Γ = 30.
2cΓ2A clumpy structure is necessary to let the long term
synchrotron afterglow to be emitted.
10/26

D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst AfterglowsModeling with the STELLA CodeNew!

The Ejecta

Immediate deceleration

Ekk
6 Mdec < cE
2 Γ2 << Mshell ⇒c2 Γ

thermalization.

53 erg is deposited into

Thermal energy Ek = Eiso,γ = 4.5 · 10

the innermost zone over δRz /c ≈ 17 s time scale. A `Thermal
Bomb' is triggered ∆tγ−ej ∼R≈ 200 s for Γ = 30.
2cΓ2A clumpy structure is necessary to let the long term
synchrotron afterglow to be emitted.

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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst AfterglowsModeling with the STELLA Code

Thermal Emission∂(ur2 )∂Jνc ∂ 2= c(ην − χab Jν ) − 2
Jν − 2(r Hν )+
∂t
r ∂r
r ∂r



∂(ur2 )1 ∂ 4
u+ 1− 3(ν ...)(3fE − 1)Jν − 2
f E Jν ,
ν ∂ν
r
r ∂r
∂Hν
2 ∂(ur)∂c= −c(χab +χsc )Hν −Hν −c (fE Jν )− (3fE −1)Jν − Ḣν,dif f
∂t
r ∂r
∂r
r
R1

Closure by Eddington factors: fE =µ2 f dµ

−1
R1

f dµ

from simplied 2D-problem−1

formal intergal solution.
O(v/c) aberration, Doppler shift, retardation;
120 groups from 50000 A to 100 keV
Source ην = χab bν , χab  f-f, b-f, lots of b-b + expansion.
Boundary conditions: Hν = hE Jν , outer: > 0; inner: < 0. pout = 0.
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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst AfterglowsModeling with the STELLA Code

Thermal Emission

Boundary conditions: Hν = hE Jν , outer: > 0; inner: < 0. pout = 0.
New!

Curvature delay: Lν,iso (tobs ) = 8π2

where t0del + Routc(tdel ) (1 − µ) = tobs

R1

2
µIν (t0del , µ)Rout(t0del )dµ,

µmin

0

dt

A

A
O
1

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dS

S

O

0

D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst AfterglowsModeling with the STELLA CodeModel Overwiew

gamma-rays

Eiso=4.5·1053 erg
thermal emission

EjectaR=1016 cm

12/26

D.A. Badjin, S.I. Blinnikov, K.A. Postnov

h=5·1013 cm, n~1010 cm-3

Thermal Emission in Gamma-Ray Burst AfterglowsModeling with the STELLA CodeModel Overwiew

A dense `wall' of matter.
1D moment radiative transfer equation, Eddington factor
closureLagrangean radiation hydrodynamics implicit solver

12/26

New!

time-dependent ionizationNew!

γ -ray aected microphysics and heating

New!

Additional heating by the ejecta

New!

Curvature delay

D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst Afterglows

Results of the Simulation

Results: The Shell Hydrodynamics
I A full ionization ⇒PE and X-ray emission IS
NOT ABSORBED by theshell.

I The radiation pressure

Prompt Emission
Front

dominates and governs
matter motions.
I The ejecta launches
a strong shock, smearedby the TE, exhausting its
energy through the innerboundary.
I
Coasting
velocity≈3000
km/s. Free

expansion.

13/26

TE

TE

TE

Matter temperature, velocity
and TE eectiveR
4
temperature σTrad= π Jν dν at the time, the PE
has illuminated nearly half of the shell.

D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst Afterglows

Results of the Simulation

Thermal Emission properties
The high temperature peak produces a keV X-ray pulse following the PE front.
Then comes a longer sub-keV soft X-ray tail (accounts for the most of the TE
luminosity) and less energetic tails: UV, optical, IR  the softer the longer.

Prompt Emission
Front

TE

14/26

TE

TE

D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst Afterglows

Results of the Simulation

Thermal Emission properties
Shell curvature ⇒ bright pulses turn into long at suppressed bumps/plateauswith following characteristic times:
I Rise time ≈ radiation cooling time, e.g. ∼10-100 s in keV X-rays, 102 − 103 s
in soft X-rays.
I Plateau duration ≈ (1 − cos(θjet ))R/c ≈ 5000 s for the on axis observer
I Fade time, a combination of the radiation cooling time and an o-axis angle
delay.
⇒ No plateau for frequencies with radiation cooling times > 5000 s.
I NB. This picture may be complicated by light diusion/reverberation in theshell.
dt

A

A
O
1

14/26

dS

S

O

0

D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst Afterglows

Results of the Simulation

Luminosity light curves

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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst Afterglows

Results of the Simulation

Luminosity spectral density

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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst Afterglows

Results of the Simulation

Stellar Magnitudes (Fluxes)

The most visible displays of TE in optics should be looked for in high-redshiftobjects' LCs
17/26

D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst Afterglows

Results of the SimulationEect on Color Evolution
Color evolution fromblue to red.
Valuable for thedimmest afterglows.
Negligible for the brightones.
Red shift suppresses its
visibility.

∆(V − R) = (V − R)Sync+T E − (V − R)Sync

18/26

D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst Afterglows

Comparison with Observations

Observations: Optical Irregularities
I Irregularity ≡ a long term deviation from a power law fading

I Possible candidates to be explained by TE.
GRB

z020124021004

3.198
2.3351030328030429X
050904
Model

1.52
2.65
6.29
any

1
Eγ,iso1053 erg

1.6
0.12

3.3
0.133
632
4.5

4
Rbump

mag
18.36
16.2
19.05
19.4
20.9
20.5
See

t5peak

days
0.47
0.08
0.9
0.28
1.2
0.32
the

t6bump

days
≈7

0.5
1.7
1.2

≈4
≈7

plots

β

time-aver.
0.56
0.67
0.36
0.22
...

1 converted into 1 keV  10 MeV range; 2 15-150 keV only, due to lack ofobservations; 3 the peak luminosity was 5 · 1053 erg/s; 4 the magnitude at thedeviation maximum; 5 the moment of the maximum; 6 the irregularity duration

I The afterglows with irregularities seem systematically `bluer'(their spectral slopes β are lower than typical β = 0.7).

19/26

D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst Afterglows

Comparison with Observations

Optical Irregularity Model
GRB 021004, z≈3

GRB 050904, z=6.29

The relativistic ejecta encounters a strong density jump and radiates thesynchrotron emission ⇒ the smooth onset (Nakar & Granot, 2007 ).
A characteristic moment of the onset is (1 + z)10∆tγ−sh ∼ (1 + z)2000 s,
nearly that is observed. Heated matter then radiates its internal energy via
the TE ⇒ at bump/plateau and fast fading.
20/26

D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst Afterglows

Comparison with Observations

X-ray Irregularities

X-RAY PLATEAUS (or at bumps)
I X-ray light curves GRB
GRB 050904 and GRB 070110
050904 (also had an OI) and
GRB 070110 (taken from Troja
et al., 2007 ). 070110 had Fν ≈2µJy @1 keV, ⇔ Lν ≈ 5 ·1029 erg s−1 Hz−1 @3.3 keVduring the plateau, consistently
with model spectra.
I The smooth onset  the same
like in optics (?)
I But, an increasing HR[1−10 keV ]from 1 to 1.5 was[0.2−1 keV ]reported.

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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst Afterglows

Comparison with Observations

X-ray Irregularities

X-RAY PLATEAUS (or at bumps)
I X-ray light curves GRB
GRB 050904 and GRB 070110
050904 (also had an OI) and
GRB 070110 (taken from Troja
et al., 2007 ). 070110 had Fν ≈2µJy @1 keV, ⇔ Lν ≈ 5 ·1029 erg s−1 Hz−1 @3.3 keVduring the plateau, consistently
with model spectra.
I The smooth onset  the same
like in optics (?)
I But, an increasing HR[1−10 keV ]from 1 to 1.5 was[0.2−1 keV ]reported.

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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst Afterglows

Comparison with Observations

X-ray Irregularities

The hardness decit may be overcome
taking into account:Bremsstrahlung of superthermal electrons (the adopted PE
could heat them by Compton scattering up to 60 keV). The
single-temperature uid approximation should be rejected
Scattered photons of the PE soft tail. Those from 1  60 keV
range scattered toward the observer could provide an isotropic

49 erg/s, varying on theluminosity equivalent of order 10
curvature delay time scale.

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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst Afterglows

Comparison with Observations

X-ray Irregularities

The hardness decit may be overcome
taking into account:Bremsstrahlung of superthermal electrons (the adopted PE
could heat them by Compton scattering up to 60 keV). The
single-temperature uid approximation should be rejected
Scattered photons of the PE soft tail. Those from 1  60 keV
range scattered toward the observer could provide an isotropic

49 erg/s, varying on theluminosity equivalent of order 10
curvature delay time scale.

22/26

D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst Afterglows

Comparison with Observations

Quasi-Supernova

An extreme case: TE does not escapeHν,in = 0.
I Total peak luminosity ∼1049 erg/s, X-rays unaected(⇒ depend mostly on gamma-

through the inner boundary,

Quasi-supernova and GRB 060218

rays); in optics: a bright ash(like a shock breakout) → a longbump/plateau.
I Expansion velocity ∼ 6.5 ·104 km/s. A very energetic

supernova.

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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

GRB 060218

XRT

Thermal Emission in Gamma-Ray Burst Afterglows

Comparison with Observations

Quasi-Supernova

An extreme case: TE does not escapeHν,in = 0.
I Total peak luminosity ∼1049 erg/s, X-rays unaected(⇒ depend mostly on gamma-

through the inner boundary,

Quasi-supernova and GRB 090618

rays); in optics: a bright ash(like a shock breakout) → a longbump/plateau.
I Expansion velocity ∼ 6.5 ·104 km/s. A very energetic

supernova.

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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst Afterglows

Comparison with Observations

Quasi-Supernova

An extreme case: TE does not escapeHν,in = 0.
I

Similar double-bumped

light curves for GRB 060218(sn2006aj) (Campana et al.
2006 ). Also reported an X-ray
blackbody component with aplateau of > 3000 s duraion.
I QSn  nonphysical in 1D,
but illustrates the importanceof radiation around an opacity
jump (may be natural in 2D or
3D cases, near surfaces dividing
hot and cold dense matter, e.g.
jet channel walls).

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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

through the inner boundary,

Quasi-supernova and GRB 060218

GRB 060218

XRT

Thermal Emission in Gamma-Ray Burst Afterglows

Comparison with Observations

Quasi-Supernova

I A curious consequence for the GRB-SN connection and central
engine theory:
as the sn-bump is allowed to originate in the environment (e.g. dueto an explosion driven by radiation),
it removes the necessity for the central engine of the collimated`failed supernova' outow, to launch a widespread `successful' one
as well. The latter occurs outside.

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D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Thermal Emission in Gamma-Ray Burst Afterglows

Conclusions

Conclusions

detectable
Thermal Emission, plateaus, bumps, irregularities
A possibility of o-center supernova-like explosions ⇒ a way
to explain the GRB-SN connection without placing
Massive structures of circumstellar matter ⇔constraints on GRB central engine.
An important role of radiation ⇒ a necessity in self-consistent
relativistic multidimensional

25/26

D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Radiation hydrodynamics codes.

Thermal Emission in Gamma-Ray Burst Afterglows

Conclusions

Conclusions

detectable
Thermal Emission, plateaus, bumps, irregularities
A possibility of o-center supernova-like explosions ⇒ a way
to explain the GRB-SN connection without placing
Massive structures of circumstellar matter ⇔constraints on GRB central engine.
An important role of radiation ⇒ a necessity in self-consistent
relativistic multidimensional

25/26

D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Radiation hydrodynamics codes.

Thermal Emission in Gamma-Ray Burst Afterglows

Conclusions

Conclusions

detectable
Thermal Emission, plateaus, bumps, irregularities
A possibility of o-center supernova-like explosions ⇒ a way
to explain the GRB-SN connection without placing
Massive structures of circumstellar matter ⇔constraints on GRB central engine.
An important role of radiation ⇒ a necessity in self-consistent
relativistic multidimensional

25/26

D.A. Badjin, S.I. Blinnikov, K.A. Postnov

Radiation hydrodynamics codes.

Thermal Emission in Gamma-Ray Burst Afterglows

Conclusions

Thank you for your attention!

gamma-rays

Eiso=4.5·1053 erg
thermal emission

EjectaR=1016 cm

26/26

D.A. Badjin, S.I. Blinnikov, K.A. Postnov

h=5·1013 cm, n~1010 cm-3

Thermal Emission in Gamma-Ray Burst Afterglows