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INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
INTEGRAL School, Les Diablerets (CH), March/April 2000
“Radionuclides and Gamma-Ray Line Astronomy”“Radionuclides and Gamma-Ray Line Astronomy”
Invited LecturesInvited Lecturesby
Roland DiehlMPE Garching
•• Part I:Part I: Gamma-Rays and NucleosynthesisGamma-Rays and Nucleosynthesis–– Nucleosynthesis ProcessesNucleosynthesis Processes
–– Radioactive DecayRadioactive Decay
–– Cosmic Nucleosynthesis SitesCosmic Nucleosynthesis Sites
•• Part II:Part II: Observed Cosmic RadioactivitiesObserved Cosmic Radioactivities–– SupernovaeSupernovae
–– Diffuse Radioactivities & Various ConnectionsDiffuse Radioactivities & Various Connections
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
Part IIPart II
• Observed Cosmic Radioactivitiesa) Supernovaeb) Diffuse Radioactivities
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
The Energy from Radioactivity in SN1987AThe Energy from Radioactivity in SN1987A•• Early Light Curve Dominated by Early Light Curve Dominated by 5656Ni and Ni and 5757Co RadioactivityCo Radioactivity
(Gamma-Ray Lines Detected by SMM and OSSE, respectively)(Gamma-Ray Lines Detected by SMM and OSSE, respectively)
•• Late Light Curve Power Source Unknown:Late Light Curve Power Source Unknown:~10~10-4 -4 MMoo of of 4444Ti? Pulsar?Ti? Pulsar?
•• Detection by INTEGRAL Possible, if Detection by INTEGRAL Possible, if 4444Ti SourceTi Source
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
Supernovae: Constraints from Gamma-Ray LinesSupernovae: Constraints from Gamma-Ray Lines
• SN 1987A� Core-Collapse; d~55kpc� Early 56Ni Lines
(SMM & balloons)
−−−−>>>> Enhanced Mixing�
57Co Lines (OSSE)
−−−−>>>> [57Ni/56Ni] ratio ~1.5-2 [57Ni/56Ni] solar
• SN 1991T� Peculiar SNIa; d~17Mpc� Indication of 56Co Lines
(COMPTEL)
−−−−>>>> MNi~0.6-3.3 Mo
• SN1998bu� SNIa; Unusually-high
Reddening; d~8-12 Mpc� Limits on Lines
(OSSE; COMPTEL)
Constrain Models
SN1998bu Model Light Curves
0.0E+00
2.0E-05
4.0E-05
6.0E-05
8.0E-05
10925 10950 10975 11000 11025 11050 11075 11100 11125 11150 11175 11200 11225
Date (TJD)
Ph
oto
n F
lux
(cm
-2s
-1)
deflagration
delayed detonation
detonation
sub-Chandrasekhar
from models by Jord i Gomez-Gomar (July 98)
GRO Obs ervations
COMPTEL 2 σσσσ limit fromspectral analysis
1238 keV11.6 Mpc
Roland Diehl 08/99
(Kurfess et al. 1992; Clayton et al. 1992)
(Morris et al. 1995;1997)
(Leising et al. 1999; Georgii et al. 1999)
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
57Ni
57Fe
e-capture
ττττ =52 h
57Co
γγγγ 136 keV (11%)
ττττ = 390 d
γγγγ 1370 keV
3/2-
3/2-
7/2-
5/2-
e- - capture
3/2-
1/2-
γγγγ 122 keV (89%)
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
56Ni
56Fe
e--capture (98%)
γγγγ 750 keV (50%)
ττττ =8.8 d
56Co
γγγγ 847 keV (100%)
ττττ = 111.3 d
γγγγ 812 keV (86%)
0+
1+
2+
4+
2+
0+
4+
γγγγ 1238 keV (68%)
e- - capture (81%) γγγγ 158 keV (100%)
3+
0+ γγγγ 270+480 keV (36%)
3,4+ ββββ+ - decay(19%,E~0.6MeV) γγγγ’s 3.2,2.8,2.0,1.0,
1.4,1.8 MeV (2-16%)
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
5656Co Line Indications from SN1991T in COMPTEL DataCo Line Indications from SN1991T in COMPTEL Data
•• SN1991T:SN1991T:� in NGC4527 on 10 Apr 1991�Distance 9.... 17 Mpc�Peculiar SNIa
early: no Si absorption, Fe emission instead;overluminous;late: ~standard SNIa
•• COMPTEL Observation Result:COMPTEL Observation Result:�Observations at Days 66-79, 176-190�3.3σσσσ from combined Observations in
847 and 1238 keV Lines�Flux:
8.9 (±3.4 ±2.7) 10-5 ph cm-2 s-1 (combined)5.3 10-5 ph cm-2 s-1 (847 keV only)3.6 10-5 ph cm-2 s-1 (1238 keV only)
� Inferred 56Ni Mass: ~ 2 Mo (0.62...2.0...3.3 Mo)
� Large Uncertainties ofModel Yields (Variety of Types)& Gamma-Ray Measurement
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
SN 1998 buSN 1998 bu• Discovery on May 9.9, 1998(Villi),
Ia Identification on May 14(no H lines; SiII absorption at max; Meikle et al.; Ayani et al.),SN Event Inferred on May 1..2 (from Plate Post-Discovery on May 3)
• Host Galaxy M96 / NGC 3368 (RA 10 46.8 Dec 11 50; l=234.5, b=57.0)
• ~Closest SNIa: D~8...12 Mpc (D98bu~0.7 D91T)(Ceph.8.2; Tully-F.~8.1; HST-Ceph.11.6±0.8; PN 9.6±0.6)
• “Standard” Type-Ia Lightcurve & Spectra in IR,U,V,B; <VBmax>=11.89• Extinction AV~0.94 ±0.2 mag; Unusual Reddening (Host Galaxy Dust?)
CGRO Observations:721.5 19May-22May03 234.4/57.0723.5 27May-02Jun 06 230.1/55.2725.5 02Jun-16Jun 14 230.2/55.2726.5 16Jun-23Jun 07 230.2/55.1727.7 30Jun-07Jul 07 239.0/58.8728.5 21Jul-11Aug 21 231.6/55.8729.5 11Aug-25Aug 14 231.6/55.8730.5 25Aug-08Sep 14 236.3/55.3731.5 08Sep-22Sep 14 232.3/58.7
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
10900 10950 11000 11050 11100 11150 11200 11250
0,0
2,0x10-5
4,0x10-5
6,0x10-5
8,0x10-5
1,0x10-4
2σ upper limit from
imaging analysis
2σ upper limit from
spectral analysis
Deflagration Delayed Detonation Detonation Sub-Chandrasekar W7 W7DT HeCD WDD2
Pho
ton
flux
[1/(
cm2 s
ec)]
TJD
10900 10950 11000 11050 11100 11150 11200 11250
0,0
1,0x10-5
2,0x10-5
3,0x10-5
4,0x10-5
5,0x10-5
6,0x10-5
2σ upper limit from
imaging analysis
2σ upper limit from
spectral analysis
Deflagration Delayed Detonation Detonation Sub-Chandrasekar W7 W7DT HeCD WDD2
Pho
ton
flux
[1/(
cm2 s
ec)]
TJD
SN1998bu:SN1998bu: COMPTEL Limits on COMPTEL Limits on 5656Ni Decay LinesNi Decay Lines
�847 keV Line(for 11.3 Mpc)
� Ispectral<4.1 10-5 ph cm-2 s-1
� Iimaging<5.8 10-5 ph cm-2 s-1
� I < 5 10-5 ph cm-2 s-1
�1238 keV Line
� Ispectral<2.3 10-5 ph cm-2 s-1
� Iimaging<3.2 10-5 ph cm-2 s-1
� I < 3 10-5 ph cm-2 s-1
• “Fast” Models (He Cap, W7DT) UnlikelyGeorgii et al., AIP (Proc. 5th Comp.Symp.) 2000
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
Massive Close Binary
White Dwarf Merge
BinaryMass Transfer
WD Giant
He Layer
He Shell Flash
WD at MCh
CentralC Ignition
SN Ia
C/O Layer
Supernova IaSupernova IaModelsModels
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
4444Ti Decay as Nucleosynthesis ProbeTi Decay as Nucleosynthesis Probe
• Decay Scheme:
���� 3 gamma-ray lines
fifi Probe of IndividualProbe of IndividualSupernova Events!Supernova Events!
• Decay Time:(Laboratory Measurements)now settled to 89y!
• 44Ti Decay in SNR: EC Suppression through Ionization?
40
45
50
55
60
65
70
Win
g et al
. 196
5More
land e
t al. 1
965
Freke
rs et
al. 1
983
Alburg
er et
al. 1
990
Norman
et al
. 199
6Mei
ßner et
al. 1
995
Wiet
feld
t et a
l. 199
7Norm
an et
al. 1
998
Görres
et a
l. 199
8Ahm
ad et
al. 1
998
T 1
/2 (4
4T
i, y
ear
s)
Measurement ∗∗∗∗ =decay curve measurement
∗∗∗∗ ∗
Cas
A D
isco
ver
y
44Ti44Ti 44Ca44Ca
e-capture ( 99.3 %)
γγγγ 0.0784 MeV ( 98.3 % )* γγγγ 0.0784 MeV ( 98.3 % )*
ττττ =89y
44Sc
44Sc
γγγγ 1.157 MeV(100%) γγγγ 1.157 MeV(100%)
ττττ = 5.4 h
γγγγ 0.0679 MeV ( 100 % )* γγγγ 0.0679 MeV ( 100 % )*
e-capture ( 0.7 % )
γγγγ 1.15 MeV (1%)
e- - capture & ββββ+ - decay (98.95% )
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
Core Collapse Supernovae: Cas ACore Collapse Supernovae: Cas A
Cas A COMPTEL Phase 1-5
Energy (keV)
Cou
nts
/ bin
800 1000 1200 1400 1600 1800
-100
0
100
200
A. Iyudin et al., A&A 1994; ESA-SP 382 1997
�1.157 MeV 44Ti Line Detection (<6σσσσ) by COMPTEL�Likelihood Map Peaks @(l=111o/b=-1o)(±±±±3o) = Cas A�1.157 MeV Flux 4.2 (±0.9) 10-5 ph cm-2 s-1
� Consistent with OSSE 1.7 (±1.4) 10-5 and RXTE 2.9 (±2.0) 10-5 Flux Values
� Direct Proof of 44Ti Production in CC-SNae� Pioneering Detection of Young SNR in 44Ti Gamma-Rays
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
Cas A: Studies of SN Blastwave / ISM InteractionsCas A: Studies of SN Blastwave / ISM Interactions
• SNR Reverse Shock −> −> −> −> Hot SNR Bubble (X)
• Fermi Acceleration at Shock Discontinuity (R,X,γγγγ)• Heating of Dense Clumps/Filaments (Lines)
X-Cont(temperature)
X-Lines
IR-Lines
Radio-Continuum
Optical-Lines
Diagnostics of•Blast Wave Evolution•Ejecta & CSM Composition•Thermalization Conditions
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
X-Ray Spectroscopy Cas AX-Ray Spectroscopy Cas A
• X-Ray Lines Reveal Clumps with LargeEjecta Enrichments
• SNR Inhomogeneity Requires Mixing /Turbulence During Explosion
Ref.: Hughes et al., ApJ 528, 2000 (Chandra Observation)
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
IR Spectroscopy of Cas AIR Spectroscopy of Cas A
NeII Line (dotted line) and Silicate Line (full line) Images of SNR(over optical color image) (from ISOCAM, Douvion et al. A&A, 2000)
• Ne (and Ar, S) found in (same) Fast-Moving Knots / Ejecta Clumps• (Optical Spectroscopy: O, S, Ar Incompletely Mixed in Knots)• Anticorrelation of NeII and Silicates=> Macroscopic but Heterogeneous Mixing of SNR During/Before Dust
Formation?
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
Cas A Asymmetries and JetCas A Asymmetries and Jet
• Jet Properties� In NE Edge of SNR�Extending 3’ Beyond SNR�25o Opening Angle, ~6o out of Plane of
Sky�7000 km/s < v < 13000 km/s�O, S, Ar Line Emission Knots; some N-
rich Knotse.g. Fesen & Gunderson ApJ 1996
• Ejecta Plumes of SN?�Fast-Moving Knots: Mantle/Core
Material?�Fast Moving Flocculi: Envelope
Material?�Mixed-Emission Knots: Mixed SN
Layers?
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
Supernova Remnants: Evolutionary StatesSupernova Remnants: Evolutionary States
Gamma-Rays Can Extend Presently-Favourable X/R/ORegime:� Search for New SNR� Diagnostics from Line Shape & Light Curve
10 100 1000 10000 105
SN:Optical,~X,~γγγγ(57Co)
γγγγ-Rays 44Ti (ττττ~90y)
γγγγ-Rays 26Al (ττττ~106y)
optical
X-ray
Radio,~nonthermal X, γγγγ-rays
SNR Age (years)
Log L
CasA
Crab,
1006,
Vela
1987A
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
Issues in CC-Supernova ModelsIssues in CC-Supernova Models
• Explosion Mechanism = Competition Between Infall and Neutrino Heating• 3D-Effects Important for Energy Budget AND Nucleosynthesis• Location of Ejecta/Remnant Separation• 44Ti Produced at r < 103 km from αααα-rich Freeze-Out, ====> > > > Unique Probe (+Ni Isotopes)
ννν
νννν ν
ννννν νν
ν
νν
ν
ν
ν
νν
ν
GravitationalCore Collapse
SupernovaShock Wave
Shock RegionExplosive Nucleosynthesis
Proto-Neutron StarNeutrino Heating
of Shock Region from Inside
Shell-StructuredEvolved Massive Star
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
Continuum MeV Gamma-Rays from Cas AContinuum MeV Gamma-Rays from Cas A
� Hard X-Ray/MeV Gamma Regime Measurements�RXTE Non-Thermal X-Rays from SN 1006 (Allen et al. 1997)�OSSE Powerlaw Emission from Cas A (The et al. 1998; 1999)�COMPTEL MeV Continuum Emission Study (Strong et al. 1999)
� Continuum Turnover in MeV Regime?� Bremsstrahlung or Synchrotron Emission?
energy, MeV 10
-310
-210
-11 10 10
210
3
E2*
flu
x, cm
-2 s
-1 M
eV
10-6
10-5
10-4
10-3 Cas A γ-ray spectrum total in line interval 1-3 MeV minus linecontinuum 1.3-3 MeV continuum 3-10,10-30 MeV 2σ u.l.
EGRET
� SNR Model (e.g. Ellison et al.1999)
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
The The 4444Ti Mass Produced by the Cas A SupernovaTi Mass Produced by the Cas A Supernova
Derived 44Ti Amount Depends on� Date of Explosion AD1680� Distance to Cas A 3.4 kpc�
44Ti Radioactive Lifetime 89y (T1/260y)� Measured Gamma Ray Intensity 1...4 10-5 ph cm-2 s-1
44Ti-Mass of the Cas A Supernova: Sources of Uncertainties
0.00E+00
1.00E-04
2.00E-04
3.00E-04
4.00E-04
5.00E-04
6.00E-04
7.00E-04
8.00E-04
distance toCas A
time of Cas ASN event
Cas A gamma-ray line flux
Ti half lifevalues <1995
Ti half lifevalues 1998
44T
i M
ass
(Mo)
RDiehl 08/99
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
Silicon Carbide GrainsSilicon Carbide Grains
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
Supernova Grains: Supernova Grains: 4444Ti and Ti and 2828Si EnrichementsSi Enrichements
• Nuclear Burning ShouldProduce NeighbouringIsotopes at ~Similar(factor 10) Abundances
• Excess in αααα-MultiplesIndicates αααα-Rich Freeze-Out
====>>>> Supernova Origin====>>>> Supernovae Produce and
Eject 44Ti
graphite
SiC type X
δ30 S
i/28 S
i (‰
)δ2
9 Si/2
8 Si (
‰)
44Ti/48Ti
110-110-210-310-4
-800
-600
-400
-200
0
200
400
-800
-600
-400
-200
0
200
Solar
Solar
δiSi/28Si (‰) = ((iSi/28Si)Grain/(iSi/28Si)Solar-1)×1000
28Si excess
28Si excess
-1000
-500
0
500
1000
δ29 S
i/2
8 Si
(‰)
-1000 -500 0 500 1000
δ30Si/ 28Si (‰)
SiC type X
Graphite
Si3N4
Solar
δiSi/28Si (‰) = ((iSi/28Si)Grain/(iSi/28Si)Solar - 1)×1000
pure 28Si
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
Why Are We Seeing So Few Why Are We Seeing So Few 4444Ti SNae?Ti SNae?
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
A New A New 4444Ti Supernova Remnant in Vela?Ti Supernova Remnant in Vela?
• COMPTEL Spectral Analysis� Using Extended Signal as Background� Scans along Plane of Galaxy=> 1.16 MeV Line Excess in Vela Region
• COMPTEL Imaging Analysis� Using Adjacent-Energy Background� Excluding Partially-Disfunct Detector Modules� Application of MEM All-Sky Imaging=> Indication of Point Source
at/coincident with RX J0852-4622• Uncertainties:
� Instrumental Background Model� Underlying Galactic Continuum Emission� Imaging Method
−> Consistency Checks & Forther Study Required• Assessments: (Sep 1999)
� Vela Region Result not Robust Against DifferentAnalysis Approaches and Data Selections,unlike Cas A 44Ti Detection
� For RX J0852.0-4622: Evidence of a 44Ti Signal at ~2-4σ Significance
� Independent Discovery of a 44Ti SNR(GRO J 0852.0-4622) Cannot Be Claimed
GROJ0852-4642 spectrum
Energy (keV)
Photons per 20 keV
800 1000 1200 1400 1600 1800 2000
-200
0
200
400
1
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
SN Search in SN Search in 4444TiTi
• With SN Rate ~1/30yExpect Several 44Ti SourcesFrom Massive Stars
• Select Clean Region ofCOMPTEL 44Ti Dataset(±±±±90o lII)
to Derive SN-Rate Limitsfrom MC Simulations
�44Ti Ejecting SN areRelatively Rare
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
•• If If 4444Ti was Typical for Core-CollapseTi was Typical for Core-CollapseSupernovae:Supernovae: →→ Expect 3-4 SourcesExpect 3-4 Sources
•• COMPTEL Imaging SearchesCOMPTEL Imaging Searchesfor for 4444Ti Line SourcesTi Line Sources →→ Cas A (Consolidated) Cas A (Consolidated)
Vela Region (Candidate) Vela Region (Candidate) →→ < 3 Candidate Sources< 3 Candidate Sources
•• Monte Carlo Simulations withMonte Carlo Simulations with4444Ti Model Yields per SN Type,Ti Model Yields per SN Type,Galactic Extinction Model,Galactic Extinction Model,Optical Historic Record,Optical Historic Record,COMPTEL Data ConstraintsCOMPTEL Data Constraints →→ Opt. SN Frequency ~ 17 y Opt. SN Frequency ~ 17 y
4444Ti SN Frequency > 17 yTi SN Frequency > 17 y →→ 4444Ti Ejection is Not TypicalTi Ejection is Not Typical
COMPTEL Search for COMPTEL Search for 4444Ti Sources in the GalaxyTi Sources in the Galaxy
C. Dupraz et al. 1997; A. Iyudin et al. 1999; The et al. 1999
INTEGRAL School, Les Diablerets (CH) April 2000 Roland Diehl
4444Ti Gamma-Rays and Massive StarsTi Gamma-Rays and Massive Stars
• COMPTEL Survey Finds ≤≤≤≤ few 44Ti Sources• Cas A and SN1987A Produce ≥≥≥≥ Expected 44Ti (≥≥≥≥ 5 10-5 Mo)
• Core-Collapse Supernovae are No 44Ti Sources on Average• Exceptional Events Produce Galactic 44Ca (44Ti)
• Cas A: Expect Co-Produced 56Ni Ejection (Bright Light Curve) => ??
• Asymetries Observed in Ejecta / SNR / Winds
• What Is the Impact of Progenitor Evolution?(Rotation, Asymmetries)