Transcript Short Bursts - University of California, Berkeley

Short Bursts
Daniel Perley
Astro 250
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
GRBs have long been known to fall into two general
categories:
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
long burst
count rate (ct/s)
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Long Bursts
GRB Classes
45 s
time (seconds)
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
GRBs have long been known to fall into two general
categories:
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
0.8 s
short burst
count rate (ct/s)
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Short Bursts
GRB Classes
time (seconds)
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
The separate populations are statsitcally robust,
although intersecting.
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
Burst Durations
GRB Classes
N
10-2
10-1
1
10
100
1000
T90 (seconds)
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
The separate populations are statsitcally robust,
although intersecting.
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
Burst Durations
GRB Classes
long bursts
N
short bursts
10-2
10-1
1
10
100
1000
T90 (seconds)
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
GRB Classes
The two populations have different hardnesses:
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
short bursts
Hardness (S3/S2)
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Duration/Hardness
long bursts
T90 (seconds)
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Other intrinsic differences have also been noticed.
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
10-4
long bursts
10-5
Ftot (erg/cm2)
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Duration/Fluence
GRB Classes
10-6
10-7
short bursts
10-8
10-2
Daniel Perley
10-1
1
10
T90 (seconds)
Short Bursts
100
1000
Figure 1, Balasz et al. 2004
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
Before Swift
Long Burst Localization
First GRB (long burst) localized and first host identified
in 1997. Many have followed since then.
• All long GRBs located in
star-forming galaxies
• All long GRBs located in
regions with massive stars
• Coincident type Ic
supernova observed in
one case
→ Long bursts are associated
with supernovae.
However, short GRBs long eluded localization, and no
similar conclusions could be made.
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Before Swift
Short Burst Localization
The intrinsically short duration of a short burst makes
determining the position of the prompt gamma
emission even more difficult than usual.
"Best" localizations (5-50 square arcmin) generally
from Interplanetary Network.
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
5'
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Before Swift
Afterglow Nondetections
Before thist year, no short burst afterglow had been
found in any IPN or burst detection error box.
1 = 000607
5.6 arcmin2
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
2 = 001025B
24.5 arcmin2
3 = 001204
6 arcmin2
4 = 010119
3.3 arcmin2
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
= long burst
detected
= long burst
limit
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Before Swift
Galaxy Correlations
(Recent) study computes correlation function of
BATSE short burst positions with nearby galaxies.
Result: correlation significant to 2σ
No correlation seen for long bursts.
Estimate of 5-25% of GRBs from <100 Mpc
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
Burst Models
Burst Models
A large number of models had been proposed –
mostly of the same which had been previously
proposed for GRBs in general.
•
•
•
•
•
•
Daniel Perley
Black hole evaporation
SGR (magnetar) giant flares
Neutron star – neutron star mergers
Neutron star – black hole mergers
Collapsar
Neutron star collapse (supranova)
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
An early suggestion: GRBs may be the evaporation of
black holes produced in the early universe.
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
Primordial Black Holes
Burst Models
Mass: 7 × 1014 g (mc2 = 5 × 1035 erg)
→ Distance: ~few parsecs
Burst duration: <50-200 ms
N
cannot explain most
short bursts
10-2
10-1
1
10
100
1000
T90 (seconds)
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Magnetar Giant Flare
Burst Models
Massive flare on the surface of highly
magnetized neutron star.
Catastrophic magnetic field reorganization.
Some previous flares:
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
- 5 March 1979 event: 4 × 1044 ergs
(SGR 0526-66, LMC) 0.2 s
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Duration and hardness consistent with short GRBs.
Conclusions
- 27 August 1998 event: 8 × 1043 ergs
(SGR 1900+14)
0.2 s
Distance for GRB: 4 Mpc
(Virgo cluster: 20 Mpc)
But could there be much larger flares?
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Magnetar Giant Flare
Burst Models
- 5 March 1979 event:
(SGR 0526-66, LMC)
4 × 1044 ergs
0.2 s
- 27 August 1998 event:
(SGR 1900+14)
8 × 1043 ergs
0.2 s
- 27 December 2004 event
(SGR 1806-20)
2 × 1046 ergs
0.5 s
Most energetic Galactic event since Tycho.
0.8 erg/cm2 over 0.5s
Sirius: 10-4 erg/cm2/s
Full Moon: 1 erg/cm2/s
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
Magnetar Giant Flare
Burst Models
- 5 March 1979 event:
(SGR 0526-66, LMC)
4 × 1044 ergs
0.2 s
- 27 August 1998 event:
(SGR 1900+14)
8 × 1043 ergs
0.2 s
- 27 December 2004 event
(SGR 1806-20)
2 × 1046 ergs
0.5 s
Duration and hardness consistent with short GRBs.
(long ringing 'tail' would not be detectable at great distance)
Distance for GRB: 30 Mpc
(Virgo cluster: 20 Mpc)
Magnetars all young: ~104 year lifetime
(restricted to star-forming galaxies/regions)
Repetition possible over long time scales
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
Burst Models
Neutron Star-Neutron Star Merger
Closely orbiting neutron stars (d ~< solar radius) lose
energy from gravitational radiation.
Systems known to exist (binary pulsars)
Must eventually merge.
Post-merger object quickly collapses to
black hole
Very high angular momentum of system :
accretion disk forms; falls onto black hole.
G M2
Gravitational binding energy:
R
~ 1053 erg
→ Mpc/Gpc distances
Timescale for collapse: <~1 second
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
Burst Models
Neutron Star-Black Hole Merger
Closely orbiting neutron star / black
hole pair also loses energy to
gravitational radiation and merges.
Neutron star is tidally disrupted into
accretion disk; falls onto black hole.
Gravitational binding energy:
MNSc2 ~ 1054 erg
→ Mpc/Gpc distances
Timescale for accretion:
<~1 second
Supernovae can 'kick' binary out of Galaxy.
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Burst Models
Compact Object Mergers
Either type of merger:
Inspiral takes ~ 1 Gyr.
• Star formation may have ceased.
• System may have migrated from point
of origin – supernova explosions can
kick the binary well outside galactic
interior
Possibility of "mini-supernova" due to
production of radioactive elements in
ejected matter.
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
Collapsar
Burst Models
Collapsar (hypernova) model highly successful in
describing long bursts.
Collapse of iron core of highly massive star to black
hole + accretion of material (0.1-5 Msun).
Relativistic jet penetrates stellar envelope
Energies ~ 1050 erg : cosmological distances
Fallback time for stellar core: ~few seconds
too slow for short GRBs.
Significant uncertanties in calculation;
Breakout flash could be shorter?
Massive stars short-lived: would be
bound to star-forming regions
(like long GRBs)
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
Model Summary
Burst Models
PBH
giant flare merger
collapsar
Energy (erg)
1036
1046
~1050
>1050
Distance scale
pc
Mpc
Gpc
Gpc
Timescale
too short
OK
OK
too long?
Progenitor
mini-BH
young NS
old NS
binary
short-lived
star
Environment
Galaxy
star-forming
galaxies
in/near all
types of
galaxies
star-forming
galaxies
possibility of
repeat
possible
mini-SN
type Ib/Ic
supernova
Signatures
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
GRB 050509B
The Swift Era
First Swift short burst.
First X-ray afterglow: XRT provided 2.8' localization
This position is very close to large elliptical at center of
low-z cluster.
T90 = 0.040
S = 1 × 10-10
E = 3 × 1048
XRT
all units
CGS
Large elliptical
z = 0.2248
blue
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Is the burst associated with the elliptical?
Chance alignment probability very small.
inside galaxy cluster: 3%
within 45" of center: 0.07%
(no long GRB ever
seen in a cluster)
T90 = 0.040
S = 1 × 10-8
E = 3 × 1048
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
GRB 050509B
The Swift Era
XRT
Large elliptical
z = 0.2248
40 kpc
blue
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Is the burst associated with the elliptical?
Chance alignment probability very small.
inside galaxy cluster: 3%
within 45" of center: 0.07%
(no long GRB ever
seen in a cluster)
Additional arguments:
T90 = 0.040
S = 1 × 10-8
E = 3 × 1048
• Extremely short duration even for
short GRBs – putting at high redshift
(z~2) requires unrealistically short
intrinsic duration.
• Energetics of putting at high-z
similarly difficult for very short
durations.
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
GRB 050509B
The Swift Era
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
GRB 050509B
The Swift Era
No counterpart seen at other wavelengths.
Cannot be a supernova (if in cluster).
No mini-supernova observed.
T90 = 0.040
S = 1 × 10-8
E = 3 × 1048
SNIa
peak
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
HETE-II short burst.
X-ray afterglow seen. Unambiguously in low-z galaxy.
Optical transient (first ever for short GRB) detected
coincident with
X-ray position.
T90 = 0.070
S = 3 × 10-7
E = 2 × 1049
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
GRB 050709
The Swift Era
XRT
Star-forming
irregular
z = 0.160
3.8 kpc
HST
Transient
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
GRB 050709
The Swift Era
Optical light curve: power-law decay with jet break
(like long burst – no supernova bump)
Radio
T90 = 0.070
S = 3 × 10-7
Optical
E = 2 × 1049
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
X-ray
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Optical and radio (first for short GRB) transients seen.
Unambiguously associated with non star-forming galaxy
(within last Gyr) at low-z.
Not in a cluster.
T90 = 3
S = 6 × 10-7
Early-type
z = 0.258
E = 1 × 1050
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
GRB 050724
The Swift Era
2.6 kpc
XRT
Transient
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
X-ray afterglow, but no optical/radio transient.
Inside a cluster - numerous possible hosts.
T90 = 0.6
Elliptical
z = 0.722
XRT
S = 6 × 10-7
E = 1 × 1050
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
GRB 050813
The Swift Era
Elliptical
z = 0.719
Elliptical
z = 0.73
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
GRB 050906
The Swift Era
No X-ray afterglow detected.
BAT position consistent with IC 326.
p ~ 0.1%
BAT
T90 = 3
IC 326
z = 0.0308
S = 6 × 10-8
E = 1 × 1047
at 133 Mpc
IC 327
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
GRB 050925
The Swift Era
Soft, thermal spectrum.
Galactic latitude: b = - 0.1°
Strong radio source – no optical or X-ray detections.
SGR flare
('new' SGR)
T90 = 0.13
S = 8 × 10-8
E = 1 × 1040
at 20 kpc
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
GRB 051103
The Swift Era
IPN detection of bright short GRB.
regions of M81.
M 82
Irr
z=0
p ~ 0.5%
T90 = 0.17
Consistent with outer
M 81
Sb
z=0
S = 2 × 10-5
E = 5 × 1046
at 4 Mpc (M81)
~ 1051
at 500 Mpc
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
GRB 051105A
The Swift Era
No X-ray afterglow detected.
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
BAT
T90 = 0.13
S = 2 × 10-8
E=?
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
Daniel Perley
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
Recent Short Bursts
The Swift Era
host
energy
(erg)
050509B 0.2248
E (cl)
050709
0.160
050724
trans
most likely origin
3 × 1048
X
NS-NS/BH merger
Irr
2 × 1049
XO
NS-NS/BH merger
0.258
early
1 × 1050
XOR NS-NS/BH merger
050813
0.72
E (cl)
2 × 1050
X
050906
0.031?
S
1 × 1047
050925
Galaxy
051103
0?
051105A
?
redshift
Daniel Perley
~ 1040
Sb?
5 × 1046
NS-NS/BH merger
giant flare?
large SGR flare
giant flare?
?
Short Bursts
9 November 2005
Classes of GRBs
Long Bursts
Short Bursts
Durations
Duration vs. Hardness
Duration vs. Fluence
Short Bursts before Swift
Long Burst Localization
Short Burst Localization
Afterglow Nondetections
Galaxy Correlations
Short Burst Models
Primordial Black Holes
Magnetar Giant Flare
NS-NS Merger
NS-BH Merger
Collapsar
Summary
Conclusions
The Swift Era
•
•
•
•
Most short bursts are due to compact object
mergers.
Short bursts are beamed.
Some short bursts may be due to magnetar
giant flares in other galaxies, but a definitive
example is still lacking.
Short bursts occur more frequently per volume
than long bursts (or are beamed less), but are
intrinsically fainter.
Short Bursts since Swift
GRB050509B
GRB050709
GRB050724
GRB050813
GRB050906
GRB050925
GRB051103
GRB051105A
Summary
Conclusions
Daniel Perley
Short Bursts
9 November 2005