short bursts
DESCRIPTION
Short Bursts. Daniel Perley Astro 250 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 - PowerPoint PPT PresentationTRANSCRIPT
Short Bursts
Daniel PerleyAstro 250
9 November 2005
Long BurstsGRB Classes
Daniel Perley 9 November 2005Short Bursts
GRBs have long been known to fall into two general categories:
time (seconds)
coun
t rat
e (c
t/s)
45 s
l o n g b u r s t
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
Short BurstsGRB Classes
Daniel Perley 9 November 2005
time (seconds)
coun
t rat
e (c
t/s)
short burst0.8 s
GRBs have long been known to fall into two general categories:
Short Bursts
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 DurationsGRB Classes
Daniel Perley 9 November 2005
T90 (seconds)
N
The separate populations are statsitcally robust, although intersecting.
10-110-2 1 10 100 1000
Short Bursts
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 DurationsGRB Classes
Daniel Perley 9 November 2005
T90 (seconds)
N
10-110-2 1 10 100 1000
The separate populations are statsitcally robust, although intersecting.
short bursts
l o n g b u r s t s
Short Bursts
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
Duration/HardnessGRB Classes
Daniel Perley 9 November 2005
T90 (seconds)
The two populations have different hardnesses:
Har
dnes
s (S
3/S2)
short bursts
l o n g b u r s t s
Short Bursts
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
Duration/FluenceGRB Classes
Daniel Perley 9 November 2005
Other intrinsic differences have also been noticed.
T90 (seconds)10-110-2 1 10 100 1000
F tot (e
rg/c
m2 )
10-8
10-7
10-6
10-5
10-4
Figure 1, Balasz et al. 2004
l o n g b u r s t s
short bursts
Short Bursts
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
Long Burst Localization
Daniel Perley 9 November 2005
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.
Short Bursts
Before SwiftClasses 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
Short Burst Localization
Daniel Perley 9 November 2005
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 Bursts
5 '
Before SwiftClasses 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
Afterglow NondetectionsBefore Swift
Daniel Perley 9 November 2005
Before thist year, no short burst afterglow had been found in any IPN or burst detection error box.
Short Bursts
1 = 000607 5.6 arcmin2
2 = 001025B 24.5 arcmin2
3 = 001204 6 arcmin2
4 = 010119 3.3 arcmin2
= long burst detected
= long burst limit
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
Galaxy CorrelationsBefore Swift
Daniel Perley 9 November 2005
(Recent) study computes correlation function of BATSE short burst positions with nearby galaxies.
Short Bursts
Result: correlation significant to 2σ
No correlation seen for long bursts.
Estimate of 5-25% of GRBs from <100 Mpc
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 ModelsBurst Models
Daniel Perley 9 November 2005
A large number of models had been proposed – mostly of the same which had been previously proposed for GRBs in general.
• Black hole evaporation• SGR (magnetar) giant flares• Neutron star – neutron star mergers• Neutron star – black hole mergers• Collapsar• Neutron star collapse (supranova)
Short Bursts
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
Primordial Black HolesBurst Models
Daniel Perley 9 November 2005
An early suggestion: GRBs may be the evaporation of black holes produced in the early universe.
T90 (seconds)
N
10-110-2 1 10 100 1000
Mass: 7 × 1014 g (mc2 = 5 × 1035 erg)
→ Distance: ~few parsecs
Burst duration: <50-200 ms
cannot explain most short bursts
Short Bursts
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 FlareBurst Models
Daniel Perley 9 November 2005
Massive flare on the surface of highly magnetized neutron star.
Catastrophic magnetic field reorganization.
Some previous flares:
- 5 March 1979 event: 4 × 1044 ergs (SGR 0526-66, LMC) 0.2 s
- 27 August 1998 event: 8 × 1043 ergs (SGR 1900+14) 0.2 s
Duration and hardness consistent with short GRBs.
Distance for GRB: 4 Mpc (Virgo cluster: 20 Mpc)
But could there be much larger flares?
Short Bursts
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 FlareBurst Models
Daniel Perley 9 November 2005
- 5 March 1979 event: 4 × 1044 ergs (SGR 0526-66, LMC) 0.2 s
- 27 August 1998 event: 8 × 1043 ergs (SGR 1900+14) 0.2 s
- 27 December 2004 event 2 × 1046 ergs (SGR 1806-20) 0.5 s
0.8 erg/cm2 over 0.5s
Most energetic Galactic event since Tycho.
Sirius: 10-4 erg/cm2/sFull Moon: 1 erg/cm2/s
Short Bursts
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 FlareBurst Models
Daniel Perley 9 November 2005
- 5 March 1979 event: 4 × 1044 ergs (SGR 0526-66, LMC) 0.2 s
- 27 August 1998 event: 8 × 1043 ergs (SGR 1900+14) 0.2 s
- 27 December 2004 event 2 × 1046 ergs (SGR 1806-20) 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
Short Bursts
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
Neutron Star-Neutron Star MergerBurst Models
Daniel Perley 9 November 2005
Gravitational binding energy:
~ 1053 erg
→ Mpc/Gpc distances
Timescale for collapse: <~1 second
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.
Short Bursts
G M2
R
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
Neutron Star-Black Hole MergerBurst Models
Daniel Perley 9 November 2005
Gravitational binding energy: MNSc2 ~ 1054 erg
→ Mpc/Gpc distances
Timescale for accretion: <~1 second
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.
Short Bursts
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
Supernovae can 'kick' binary out of Galaxy.
Compact Object MergersBurst Models
Daniel Perley 9 November 2005
Either type of merger:
Inspiral takes ~ 1 Gyr.
• Star formation may have ceased.
• System may have migrated from point of origin – supernova explosions cankick the binary well outside galacticinterior
Possibility of "mini-supernova" due to production of radioactive elements in ejected matter.
Short Bursts
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
CollapsarBurst Models
Daniel Perley 9 November 2005
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)
Short Bursts
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 SummaryBurst Models
Daniel Perley 9 November 2005
PBH giant flare merger collapsarEnergy (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
Signatures possibility of repeat
possible mini-SN
type Ib/Ic supernova
Short Bursts
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 050509BThe Swift Era
Daniel Perley 9 November 2005Short Bursts
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.
XRT
Large ellipticalz = 0.2248
blue
T90 = 0.040
S = 1 × 10-10
E = 3 × 1048
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
all units CGS
GRB 050509BThe Swift Era
Daniel Perley 9 November 2005Short Bursts
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)
XRT
Large ellipticalz = 0.2248
blue
40 kpc
T90 = 0.040
S = 1 × 10-8
E = 3 × 1048
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 050509BThe Swift Era
Daniel Perley 9 November 2005Short Bursts
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
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
Additional arguments:
• 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.
GRB 050509BThe Swift Era
Daniel Perley 9 November 2005Short Bursts
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
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
SNIapeak
GRB 050709The Swift Era
Daniel Perley 9 November 2005Short Bursts
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.
XRT
HST Transient
Star-forming irregularz = 0.160
3.8 kpc
T90 = 0.070
S = 3 × 10-7
E = 2 × 1049
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 050709The Swift Era
Daniel Perley 9 November 2005Short Bursts
Optical light curve: power-law decay with jet break (like long burst – no supernova bump)
T90 = 0.070
S = 3 × 10-7
E = 2 × 1049
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
X-ray
Optical
Radio
GRB 050724The Swift Era
Daniel Perley 9 November 2005Short Bursts
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.
Transient
Early-typez = 0.258
XRT
2.6 kpc
T90 = 3
S = 6 × 10-7
E = 1 × 1050
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 050813The Swift Era
Daniel Perley 9 November 2005Short Bursts
X-ray afterglow, but no optical/radio transient.
Inside a cluster - numerous possible hosts.
XRT
Ellipticalz = 0.719
Ellipticalz = 0.73
Ellipticalz = 0.722
T90 = 0.6
S = 6 × 10-7
E = 1 × 1050
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 050906The Swift Era
Daniel Perley 9 November 2005Short Bursts
No X-ray afterglow detected.
BAT position consistent with IC 326.
BAT IC 326 z = 0.0308
IC 327
p ~ 0.1%
T90 = 3
S = 6 × 10-8
E = 1 × 1047
at 133 Mpc
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 050925The Swift Era
Daniel Perley 9 November 2005Short Bursts
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
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 051103The Swift Era
Daniel Perley 9 November 2005Short Bursts
IPN detection of bright short GRB. Consistent with outer regions of M81.
M 81Sb z = 0
M 82Irr z = 0p ~ 0.5%
T90 = 0.17
S = 2 × 10-5
E = 5 × 1046
at 4 Mpc (M81) ~ 1051
at 500 Mpc
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 051105AThe Swift Era
Daniel Perley 9 November 2005Short Bursts
No X-ray afterglow detected.
BAT
T90 = 0.13
S = 2 × 10-8
E = ?
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 BurstsThe Swift Era
Daniel Perley 9 November 2005Short Bursts
redshift host trans most likely origin
050509B 0.2248 E (cl) 3 × 1048 X NS-NS/BH merger
050709 0.160 Irr 2 × 1049 XO NS-NS/BH merger
050724 0.258 early 1 × 1050 XOR NS-NS/BH merger
050813 0.72 E (cl) 2 × 1050 X NS-NS/BH merger
050906 0.031? S 1 × 1047 giant flare?
050925 Galaxy ~ 1040 large SGR flare
051103 0? Sb? 5 × 1046 giant flare?
051105A ? ?
energy (erg)
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
ConclusionsThe Swift Era
Daniel Perley 9 November 2005Short Bursts
• 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.
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