Transcript The empirical grounds of SN

SN-GRB Connection:
Observations and Questions
Massimo Della Valle
INAF-Osservatorio Astrofisico di
Arcetri, Firenze
Bologna, 1 Giugno, 2006
1
Outline
• Introduction
2
Outline
• Introduction
• SN 1998bw/GRB 980425, SN 2003dh/GRB 030329,
SN 2003lw/GRB 031203
3
Outline
• Introduction
• SN 1998bw/GRB 980425, SN 2003dh/GRB 030329,
SN 2003lw/GRB 031203
• Bumps (SN 2002lt & SN 2005nc)
4
Outline
• Introduction
• SN 1998bw/GRB 980425, SN 2003dh/GRB 030329,
SN 2003lw/GRB 031203
• Bumps (SN 2002lt & SN 2005nc)
• SNe-Ibc & Hypernova & GRBs rates
5
Outline
• Introduction
• SN 1998bw/GRB 980425, SN 2003dh/GRB 030329,
SN 2003lw/GRB 031203
• Bumps (SN 2002lt & SN 2005nc)
• SNe-Ibc & Hypernova & GRBs rates
• Time lag SN-GRBs
6
Outline
• Introduction
• SN 1998bw/GRB 980425, SN 2003dh/GRB 030329,
SN 2003lw/GRB 031203
• Bumps (SN 2002lt & SN 2005nc)
• SNe-Ibc & Hypernova & GRBs rates
• Time lag SN-GRBs
• GRB hosts
7
Outline
• Introduction
• SN 1998bw/GRB 980425, SN 2003dh/GRB 030329,
SN 2003lw/GRB 031203
• Bumps (SN 2002lt & SN 2005nc)
• SNe-Ibc & Hypernova & GRBs rates
• Time lag SN-GRBs
• GRB hosts
• Discussion & Conclusions
8
Outline
• Introduction
• SN 1998bw/GRB 980425, SN 2003dh/GRB 030329,
SN 2003lw/GRB 031203
• Bumps (SN 2002lt & SN 2005nc)
• SNe-Ibc & Hypernova & GRBs rates
•
•
•
•
Time lag SN-GRBs
GRB hosts
Discussion & Conclusions
Recent (exciting) Results
9
Gamma-ray bursts: prompt emission
“Brief (< 100 sec) and intense (~10-6 erg/cm2/s) flashes of
soft (~100 keV) gamma-ray radiation”
Temporal beahviour: wide variety
dt << T
Highly structured
Single pulse
10
Long and short GRBs
GRBs duration: (0.01 ÷ 100) s
The distribution is bimodal
Hardness/duration
correlation:
Paciesas
et al. 2000
short bursts are harder
All the results I will present
concern the long-duration
class of GRBs!
11
Afterglows
Long-lived counterparts at X-ray, optical, IR and radio
wavelengths
Discovery: GRB 970228 by the BeppoSAX satellite
Costa et al. 1997
Optical counterparts
soon after
van Paradijs et al. 1999
12
Jakobsson et al. 2005
13
Clues about progenitors
The distance is ~ a few Gpc  3.11015 cm
Observed flux 105/-6 erg cm2 s1
gluminosity: 1051-54 erg
14
Energetic Scale: Jets or Sphere
• GRB 990123 has been detected by the
robotic telescope ROTSE, 22s and 47s
after the g-ray trigger at V~11.7 and 8.9,
respectively. At z=1.6, the isotropic energy
release implies MV ~-35 and a global
energetic budget comparable to >Mc2
• All GRBs could be collimated events, with
opening angles q ~ 5-10 degrees (break in
the power law decay of the afterglows,
polarization)
15
And in fact the jet effect on the light curve was observed in several GRBs. Here is an
example. Due to its nature the jet break time measured from the observations (i.e.
monitoring) of the burst afterglow allows to estimate the physical aperture of the GRB
jet.
“Jet break”
Jet break time tbreak
Jet opening angle 
16
“True” energetics: correcting the energyes derived with the assumption that GRBs are
isotropic the energy crisis is relaxed. Moreover the typical energetics clusters around a similar
value of 10^51 erg which is by far more standard also in comparison to other astro sources.
Frail et al. 2001
Isotropic equivalent energy
Etrue = Eiso (1 – cos )
17
X-ray Flashes
18
Probable Sequence of GRB Events
• The central engine emits a large amount of
energy.
• Most of that energy accelerates a small
mass (~10-5 M) to speeds > 99.99% of
lightspeed (G~100/500)
• Collisions between different shells of
ejected debris creates the gamma rays.
• Collisions between ejected debris and
interstellar gas create the afterglow.
19
observer
The energy
escapes in the
form of jets…
Dense
cloud
Kinetic
Energy
The progenitors
collapses or
coalesceces, forming
a spinning BH
Progenitor
location:<108 cm
…and the
colliding
shells give
rise to the
GRB
GRB location
<1014 cm
Shock
dissipation
Afterglow
Afterglow location
<1018 cm
20
21
SNe & GRBs Facts
• ‘Early Gamma-Rays from
Supernovae’ (Colgate 1968 & 1974)
• GRB 980425 SN 1998bw
et al. 1998)
(Galama
22
• SN 1998bw was discovered on NTT images
of ESO 184 G82 at z=0.0085
• The GRB and the SN appeared spatially
(P~10-4/-5) and temporally coincident
Dt= +0.7d -2.0d (Iwamoto et al. 1998)
• SN 1998bw rivals with SN 1991T: MB =-19.5
To achieve such a luminosity about 0.5-0.7
M of Ni have to be synthesized in the
explosion. This is unprecedented for Core
Collapse events (less than 0.1 M )
• The radio emitting shell was expanding at
(mildly) relativistic velocities G~1.8 (Kulkarni et
al. 1998; Weiler et al. 1999)
23
Patat et al. 2001
24
25
Patat et al. 2001
Mg I
Na I
[O I]
[Ca II]
O I
Ca II
26
Patat et al. 2001
27
Pec Type Ic SNe
Broad lines
 Large Kinetic Energy
 “Hypernovae”
(only SN1998bw was
associated with a GRB)
Narrow lines
 “normal” KE (1051)
 Normal SN Ic
28
Pec Type Ic SNe = Hypernovae
Broad lines
 Large Kinetic Energy
 “Hypernovae”
(only SN1998bw was
associated with a GRB)
Narrow lines
 “normal” KE (1051)
 Normal SN Ic
29
Light Curves of
Supernovae & Hypernovae
Brightness alone
should not be used
to define a
hypernova, whose
main characteristic
is the high Ek~1052
ergs (see broad
spectral feautures)
30
SN 1998bw
SN 1987A
=
E ~ 30×1051ergs
E ~ 1×1051ergs
31
Circumstantial evidence:
The Bumps 1999-2003
(Bloom et al. 1999)
Della Valle et al. 2006
Della Valle et al. 2003
(MISTICI Collaboration)
32
Are the bumps representative of
signatures of incipient SNe?
Or they can be produced by different
phenomena as dust echoes or thermal reemission of the afterglow or thermal
radiation from a pre-existing SN remnant
(e.g. Esin & Blandfors 2000; Waxman & Draine 2000;
Dermer 2003)
33
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35
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40
41
42
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44
45
46
47
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The spectrum of the afterglow associated with GRB
021211, obtained during the bump, reveals the
presence of a broad absorption feature (FWHM~150
A), blueshifted by ~15000 km/s, which has been
identified withCa
CaII H+K  SUPERNOVA 2002lt
Della Valle et al. 2003
50
SN 1994I
51
Evidence for the existence of a SN/GRB
connection was circumstantial before March 2003
SN 1998bw was a peculiar Ic associated with
a peculiar GRB (genergy budget about a few
x 1047 ergs)
SN bumps were only suggestive for the
existence of a SN/GRB connection. The
spectroscopic confirmation was obtained only
in one case (SN 2002lt/GRB 021211) and based
on one spectrum (z=1). In addition the
lightcurve was different from SN 1998bw
52
2003dh /GRB 030329
The Smoking
Gun (part 1)
53
GRB 030329/SN 2003dh = Smoking Gun I
Stanek et al.2003;
Hjorth et al. 2003
8 Apr Spectrum
1 Apr Spectrum
= ?
54
55
z=0.16
Matheson et al. 2003
56
GRB 030329/SN 2003dh: facts
The spectrum is very similar to the one exhibited by the
type Ic SN 1998bw
GRB and SN events are spatial coincident and coeval
SN 2003dh was not so bright as 1998bw (0.3-0.5 M 56Ni)
Modelling
(Deng et al. 2005):
Mej ~ 7±3M; Prog = 25-40 M; MBH ~ 3 M
Fe II lines broader than [O I]
aspherical explosion
(Maeda et al. 2005, 2006)

The g-energy associated with GRB 030329
is ‘’standard’’ (6.9 x 1051 erg) Sakamoto et al. 2004
57
GRB 031203 & SN 2003lw
Malesani et al. 2004
The Smoking
Gun (part 2)
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GRB 031203/2003lw =
Smoking Gun II
• Trigger from INTEGRAL
Götz et al. 2003
• Afterglow:
X-ray (XMM) & radio (VLA)
Watson et al. 2004, Soderberg et al. 2004
• Observations:
ESO NTT & VLT
• Low redshift host galaxy (z = 0.1)
Very faint: E  1049 erg
59
Spectroscopic Observations
VLT + FORS
Malesani et al. 2004
Bright star-forming
host galaxy
SFR  10 M/yr
Z  0.1Z
AV  1.1
Prochaska et al.
Chincarini et al.
2004
2014
Broad undulations
in the continuum
close to the
maximum
60
Spectra of SN 2003lw
Host galaxy subtracted
EK = 6 x 1052 erg
M 56Ni = 0.55 M
Mej = 13 M
Mprg = 40-50 M Mazzali et al. 2006
Tagliaferri et al. 2004
Malesani et al. 2004
61
The very bright supernova 2003lw
SN 2003lw
vs
SN 1998bw
Overall similar
With E(B–V) = 1.1:
* 0.5 mag brighter
* Same colors
* Slower evolution
Malesani et al. 2004
62
See also Bersier et al. 2004; Thomsen et al. 2004, Cobb et al. 2004, Gal-Yam et al. 2004
Conclusions
The discovery of the types Ic SNe 2003dh
(Stanek et al. 2003; Hjorth et al. 2003)
and SN 2003lw (Malesani et al. 2004) in the
AGs of GRB 030329 and GRB 031203 has
conclusively linked long duration GRBs with
the death of massive stars Particularly
with a subclass of SNe-Ibc, the bright tail
of HYPs
Is the game over?
63
Not at all...
…there is an expanding frontier of ignorance…
(R. Feynman, Six Easy Pieces)
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What SN types are connected with
GRBs? (only 1998bw-like?)
There is growing evidence that GRBs can
be associated with SNe which are
different from SN 1998bw, both in the peak of
luminosity and in spectroscopic type
(SN 2002lt/GRB 021211 SN 1994 I normal Ibc 1994I)
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GRB021211/SN 2002lt
SN in XRF 030723
Lg (Fx/Fg) > 0 XRF
>-0.5 XRR
<-0.5 GRB
LC Fits: a normal SN Ic or a low-E Hyp like SN2002ap at z~0.6
Fynbo et al. 2004;
Tominaga et al.2004
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Levan et al. 672005
GRB 011121
IIn?
Garnavich et al. 2003
68
Soderberg et al. 2005
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Soderberg et al. 2005
70
Soderberg et al. 2005
XRF 040701 fainter than
2002ap/SN 1994I by 3-6
mag (i.e. MV ~ -13/-15)
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1. It is not clear whether or not only Hypernovae
are capable to produce GRBs or also “standard”
Ib/c events can do it (IIn??)
2. The distributions of the absolute mag at max of
GRB/SNe and standard Ibc are statistically
indistinguishable  effect of scanty statistic?
they derive from the same SN population? (very
heterogeneous class of objects)
• All GRB-SNe which have received a
spectroscopic confirmation belong to the bright
tail of Ibc distribution  observational bias 72?
What is the fraction of SNe-Ib/c
which produces GRBs ?
• Rate for Ib/c: 0.22 SNu (Cappellaro et al. 1999)
1.2 x 108 LB, Mpc-3 (Madau, Della Valle & Panagia 1998)
 2.6 x 104 SNe-Ibc Gpc-3 yr-1
• HYPs/Ibc ? (No absolute rate from controlled time surveys)
5-10%
Podsiadlowski et al. 2004, Della Valle 2005
73
Local rate:
Rates of GRBs
-1> ~et200
0.5-1 GRB Gpc-3GRB/Hyp
yr-1 (Schmidt
Guetta
al. 2004)
~ 0.1, 2001,
IF <fb
< 1200
-1 (Firmani
~ 1, IF
~ 2000
0.04-0.4 Gpc-3 yrGRB/Hyp
et <fb
al.-1>
2004)
-1> ~30000
-1 (Matsubayashi
/SNe-Ibc ~ 1,
<fb2005)
0.01
Gpc-3 yrGRB+XRR+XRF
etIFal.
2.6x104 SNe-Ibc Gpc-3 yr-1
<fb-1> ~500
<fb-1> ~75
(Frail et al. 2001)
Podsiadlowski et al. 2004
(Guetta, Piran & Waxman 2004)
GRB/Hyp ~1
GRB/Hyp: 25%-4%
Soderberg, Nakar & Kulkarni 2005
GRB/SNe-Ibc: 2%-0.3%Radio survey on 74 Ibc+
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Optical
Rau et al. 2006
Radio light curves of HNe
Only GRB-SNe
show strong radio
emission.
No-GRB-HNe,
like 2002ap, do
not.
Either no jets or
low-density
environments.
Soderberg et al.2006
The presence of
relativistic jets is
the mark between
GRB/XRF-HNe
and ordinary
75
SNe/HNe
Discussion and Conclusions
76
1. Long duration GRBs are closely connected
with the death of massive stars.
Spectroscopic observations have been
carried out over a large range of
redshifts (z=0.008 1998bw; z=0.03 2006aj
z=0.1 2003lw; z=0.16 2003dh; z=0.23 XRF
020903; z=0.6 GRB 050525a and possibly up to
z~1, 2002lt).
77
2. Only a very small fraction of all massive
stars appears capable to produce GRBs. SNeIb/c are the natural candidates because of
the lack of H envelope. However, this does not
seem to be sufficient: only ~ 1% of SNe-Ibc
(~10% of Hyps) produce GRBs. Some special
circumstances are requested to the GRB star
progenitor besides being “only” a massive star
(Rotation, e.g. Woosley & Hegel 2006, Binarity, e.g.
Podsiadlowski et al. 2004; Mirabel et al. 2003, Asymmetry Maeda
et al. 2006). This point is not well understood
(yet).
78
3. The unification scheme where every SNe-Ibc
is producing a GRB, XRR or XRF according to
different viewed angles (e.g. Lamb et al. 2005), is not
favored by current estimates of SN/GRB rates
and radio observations.
Unification works for <fb-1> ~ 30000 ( ~ 0o.5 )
HYP & GRB Rates give <fb-1> ~ 200 ( ~ 6o )
Radio Obs SNe-Ibc give <fb-1> < 1200 (or  > 2o .5)
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Recent Results
GRB 050525A/SN 2005cn (Della Valle et al. 2006)
GRB060218/SN 2006aj
(Campana et al. 2006)
80
GRB 050525a: a new SN connection
Blustin et al. 2005
Discovered by Swift
solid = 15-25 keV
dots = 25-50 keV
short dashed = 50-100 keV
long dashed = 100-350 keV
z=0.606 Della Valle et al. 2006
E(B-V)=0.1 Blustin et al. 2005
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Follow-up at TNG, NTT
and VLT+FORS2
Della Valle et al. 2006
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84
85
86
87
88
Hyp with short rising
time  on axis event
(Maeda et al. 2006)
89
90
+5 days
91
92
+ 10 days
93
Host galaxy of XRF060218/SN2006aj (DSS2)
z = 0.033
Mv (host) = -16
Host has brightness
Similar to SMC
Z/Z ~ 0.3
Associated with SN 2006aj
(Masetti et al. 2006)
94
Examples of Swift-XRT light curves
Steep decline common
Gets shallower around here
Nousek et al. 2005
95
…the internal energy following an adiabatic expansion
of the envelope leads to a luminosity peak at 1 day
and 1% of the observed luminosity… (Colgate & White
1964)
…in any type of SN triggered by core collapse, a
shock is generated which propagates through the
progenitor star and ejects the envelope.
Accompanying the emergence of the shock wave
through the surface of the star is a very bright
UV/X burst of radiation… (A. Burrows 1992)
96
Campana et al. 2006
3 x104 km/s
Campana et al. 2006
97
98
We have observed for the first time in a GRB a thermal
component which we have interpreted as signature of the
shock break-out (Colgate 60s)
We have caught a SN in the act of exploding (about 100s
after the collapse of the core)
We have definitely proved that SN and GRB are coeval
events
99
Summary of SN-GRB time lag
GRB
SN
+Dt
-Dt
Ref.
980425
1998bw
+0.7
-2
Iwamoto et al.
000911
Bump
+1.5
-7
Lazzati et al.
011121
2001ke
0
-5
Bloom et al. +
Garnavich et al
021211
2002lt
+1.5
-3
Della Valle et al.
030329
2003dh
+2
0
-8
-2
Kawabata et al
Matheson
031203
2003lw
0
-2
Malesani et al.
041006
Bump
2
0
Stanek et al.
050525A
2005nc
2
0
Della Valle et al.
100
Observations of SNe and bumps connected with
GRBs imply that SNe and gamma bursts are
simultaneous events. This favors the collapsar
model (Woosley 1993, Paczynski 1998, MacFadyen & Woosley 1999)
over competing theories (e.g. Supranova, Vietri & Stella 1998)
101
We have observed for the first time in a GRB a thermal
component which we have interpreted as signature of the
shock break-out (Colgate 60s)
We have caught a SN in the act of exploding (about 100s
after the collapse of the core)
We have definitely proved that SN and GRB are coeval
events
We have measured the radius of the progenitor star, to
be about 4 x 1011 cm which is typical of a W-R star.
102
SNe C-C (II,
Ib, Ic)
Red Supergiant
R~3x1013 cm
Wolf-Rayet Star
Blue Supergiant
R~4x1012 cm

103
R~4x1011 cm
104
The properties of the 4 closest SNe associated
with GRBs vary by at most 30%. The g-budget
covers about 4 order of magnitudes.
105
a) we may be seeing intrinsically similar phenomena under
different angles. GRB 030329/SN 2003dh may be viewed
~ pole-on, GRB 980425/SN 1998bw considerably off-axis
(15-30°, Maeda et al. 2005). GRB 031203/SN 2003lw may lie in
between (Ramirez-Ruiz et al. 2005)
In this scenario the g-properties are a strong function of
the angle (Eg  4 ) whereas the optical properties are not
much influenced by this relative small spread in viewing
angles.
b) GRB 060218/SN 2006aj there is an intrinsic dispersion
in the properties of the relativistic ejecta for SNe with
similar optical characteristics.  relativistic energies at
play in (local) GRB phenomenon (~ 1047- 1050 erg) are small
compared to the KE involved in the “standard” SN-Ibc
(1051 erg) or Hyp (1052 erg) explosions.
106
HL-GRBs vs. LL-GRBs
2006aj
• HL-GRBs (g-ray budget of 1051-52erg ~ SN/HN KE)
• LL-GRBs (intrinsically faint 1047-49erg ~ 10-4/-2 SN KE)
• Sampled volume 104-6 smaller  Rate LL-GRBs: 20-500 x
HL-GRBs rate (Della Valle 2006, Pian et al. 2006, Soderberg et al. 2006, Liang et al. 2006)
• LL-GRBs vs HL-GRBs  properties of SN explosions?? 
• Different properties in the central engine (=compact stellar
remnant NS vs BH)?
Nomoto et al. 2003
• Lack of tbreak implies q > 75o (cfr. 5o-10o)
• GRBs occur in star forming and low metallicity galaxies. If
they are sensitive to metallicity, we can expect systematic
differences between nearby and cosmological GRBs (the
latter produced in low-metallicity environments). e.g. GRB
050904 at z=6.3 (Kawai et al. 2005, Tagliaferri et al. 2005) is quite atypical
(duration energy content, variability).
107