stable isotope anomalies and early solar system chronology f. albarède, m. arnould, r. carlson, n....
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Stable isotope anomalies and
early Solar System chronology
Stable isotope anomalies and
early Solar System chronology
F. Albarède, M. Arnould, R. Carlson, N. Dauphas,
T. Fujii, S.Jacobsen, Q. Yin, E. Young
F. Albarède, M. Arnould, R. Carlson, N. Dauphas,
T. Fujii, S.Jacobsen, Q. Yin, E. Young
Chronometry must also separate radiogenic ingrowth from isotopic anomalies:
• Nucleosynthetic anomalies• Spallation
• Mass-independent fractionation
Assumption of mass-dependent fractionation of stable isotopes
Consistent with Urey-Bigeleisen-Mayer (1947) equilibrium fractionation theory and kinetic effects.
Additional distillation (Rayleigh) effects permitted.
Interpreting isotopic anomalies:evidence of mixing
Interpreting isotopic anomalies:evidence of mixing
Trinquier et al. (2006) Luck et al. (2003)
Internally normalized Stable isotopes
Interpreting isotopic anomaliesInterpreting isotopic anomalies
Zanda et al. (2006)
I Nucleosynthetic anomaliesI Nucleosynthetic anomalies
neutron closed-shell N = 50
neutron closed-shell N = 82
Predominance domains of the different nucleosynthetic processes
Predominance domains of the different nucleosynthetic processes
Arnould and Gariely (2003)
Detecting s- and r-process anomalies on Ba Detecting s- and r-process anomalies on Ba
11σσ iiii NN
1
10
100
1000
10000
130B
a(p)
132B
a(p)
134B
a(s)
135B
a(s,r
)
136B
a(s)
137B
a(r,s
)
138B
a(r,s
)
5
10
15
20
25
30
40
50
60
80
100
Tσ
temp (keV)
neutron cross-section in mb (Bao et al., 2000), temperature T in keV
s-process at steady-state: N mirrors
Dip of neutron cross-sections forclosed-shells (magic numbers)
Dip of neutron cross-sections forclosed-shells (magic numbers)
138Ba142Nd90Zr
88Sr
208Pb
Ba nucleosynthetic anomaliesBa nucleosynthetic anomaliesAndreasen and Sharma (2007)
Ranen and Jacobsen (2007) Carlson et al. (2007)
Mass balance equation for nucleosynthetic componentsMass balance equation for
nucleosynthetic components
f: weight fraction of each component: deviation from terrestrial abundances
Linearity also holds for isotopic ratios of a same element not for different elements
Binary (s,r) mixing in Ba from carbonaceous chondrites
Binary (s,r) mixing in Ba from carbonaceous chondrites
Andreasen and Sharma (2007)Andreasen and Sharma (2007)
Saint Severin
Murchison
Allende
Juvinas
-8
-6
-4
-2
0
2
4
6
8
10
12
14
0 5 10 15 20 25 30 35
137Ba (ppm)
13
8B
a (p
pm
)
More than two components in Ba from carbonaceous chondrites (p,s,r)
More than two components in Ba from carbonaceous chondrites (p,s,r)
Andreasen and Sharma (2007)Andreasen and Sharma (2007)
Saint Severin
Murchison
Allende Juvinas
-100
-80
-60
-40
-20
0
20
40
60
80
100
-40 -20 0 20 40 60 80
130Ba (ppm)
13
2B
a (p
pm
)
Binary mixing in Sm …
Binary mixing in Sm …
Mokoia
Grosnaja
Allende
Murray
Mighei
Orgueil
Indarch
Ucera
Peace
Homestead
Gladstone
15555
GRZ-1
-200
0
200
400
600
800
1000
1200
-600 -500 -400 -300 -200 -100 0 100
e149Sm
e 150
Sm
100
1000
10000
100000
144S
m(p
)
147S
m(r,
s)
148S
m(s
)
149S
m(r,
s)
150S
m(s
)
152S
m(r,
s)
154S
m(r)
T1/
2
5
10
15
20
25
30
40
50
60
80
100
Carlson et al. (2007)
… or not?… or not?
Mokoia
GrosnajaAllende
Murray
Mighei
Orgueil
Indarch
Ucera
PeaceHomestead
Gladstone
15555
GRZ-1
-200
0
200
400
600
800
1000
1200
-30 -25 -20 -15 -10 -5 0 5
e154Sm
e 150
Sm
Binary mixing of Mo-Ru nucleosynthetic components
Binary mixing of Mo-Ru nucleosynthetic components
Dauphas (2004)
Binary mixing of s- and r-process Os componentsBinary mixing of s- and r-process Os components
Yokoyama et al. (2007) Humayun and Brandon (2007)
Pre-solar grains and predictionsPre-solar grains and predictions
Lugaro et al. (2003) Loss of consistency for different elements
There is more than binary mixing
Issues: Issues:
•Do nucleosynthetic components have discrete isotopic properties?
•How many components are needed to account observations (deconvolution)?
•Which mineral or organic phases are the carriers?
II Field shiftII Field shift
Nuclear field shiftNuclear field shifta.k.a.
Nuclear field shifteffect of nuclear charge radius
Nuclear field shifteffect of nuclear charge radius
Point-chargeapproximation
Breit (1958)
Nuclear field shift:effect of nuclear shape
Nuclear field shift:effect of nuclear shape
4.80
4.85
4.90
4.95
5.00
5.05
5.10
142Nd 144Nd 146Nd 148Nd 150Nd
nu
clea
r ch
arg
e ra
diu
s (f
m)
0.00
0.05
0.10
0.15
0.20
0.25
0.30
qu
adrip
olar d
eform
ation
b2
Bigeleisen’s (1996) formulation of mass fractionation
is the difference in nuclear charge radii between nuclei of mass m and m’, A and B are constants
2δ r
mass independent 1/T mass dependent 1/T2
Temperature dependence of isotope fractionation between U(IV) and U(VI)Temperature dependence of isotope
fractionation between U(IV) and U(VI)
Bigeleisen (1998)
Mass-independent fractionation remains after
internal normalization!
Sites: gas-dust interaction
Evidence of non-mass dependent fractionation experiment between crown-ether and acid solution
Evidence of non-mass dependent fractionation experiment between crown-ether and acid solution
Fujii et al. (2006)
Further evidence from elution on ion-exchange resins
Levins et al.(1999)
Hfnuclear charge radii increase
smoothly
Campbell et al. (1997)
Zr: deformation of nucleus increases past the neutron closed-shell (N=50)
N=50
Odd-even staggering of Sn nuclear properties
Suggests using even-even or odd-odd for normalization!
1
10
100
1000
112Sn 113Sn 114Sn 115Sn 116Sn 117Sn 118Sn 119Sn 120Sn 121Sn 122Sn 124Sn 125Sn
neu
tro
n c
ross
-sec
tio
n (
fm)
4.58
4.6
4.62
4.64
4.66
4.68
4.7
nu
clear charg
e radiu
s (fm)
Odd-even staggering of nuclear massesOdd-even staggering of nuclear masses
-40
-30
-20
-10
0
10
20
30
58 59 60 61 62 63 64
Mi/(
Mi-
1 -
Mi+
1) -
1 (
pp
m)
Ni
Begs the question of which process control mass fractionation
Test for an effect of nuclear field shiftTest for an effect of nuclear field shift
ar
mmm
mmmr mm
i
immm ii
e211 ,
2
12
12,
2
1m
mi1
2
m
minternally normalized to
Fujii et al. (2006)
3.62
3.63
3.64
3.65
3.66
3.67
3.68
3.69
50Cr 52Cr 53Cr 54Crnu
clea
r ch
arge
rad
ius
(fm
)
Mo isotopes in carbonaceous chondrites
Mo isotopes in carbonaceous chondrites
Fujii et al. (2006)
The origin of the 54Cr anomaly
The origin of the 54Cr anomaly
1.0
10.0
100.0
1000.0
50Cr 52Cr 53Cr 54Cr
3.62
3.63
3.64
3.65
3.66
3.67
3.68
3.69
nu
clear charg
e radiu
s (fm)
10
15
20
25
30
40
50
60
80
100
Trinquier et al. (2006)T
σ
Neutron cross-sections do not separate 54Cr from 52Cr, nuclear field shift does
Extraction experiments(Fujii et al, 2002)
50
52
53
54
III Analytical issues(or the limits of mass-dependent fractionation)
III Analytical issues(or the limits of mass-dependent fractionation)
Chen et al. (2003)
Correction for analytical and instrumental mass bias assumes constant isotopic abundances
Anomalous behavior of 125TeAnomalous behavior of 125Te
Moynier et al. (2006) Fehr et al.’ (2006) data renormalization
100
1000
10000
180W 182W 183W 184W 186W
T1/
2
5.30
5.31
5.32
5.33
5.34
5.35
5.36
5.37
5.38
nu
clear charg
e radiu
s (fm)
100
1000
10000
T1/
2
5.33
5.34
5.35
5.36
5.37
5.38
5.39
5.4
5.41
5.42
nu
clear chag
e radiu
s
Risky normalisation (odd/even ratio)
Also 61Ni
Pb: the double closed shell at mass 208(Z=82, N=126)
Pb: the double closed shell at mass 208(Z=82, N=126)
0.1
1
10
100
1000
204Pb 206Pb 207Pb 208Pb
T1/
2
5.465
5.470
5.475
5.480
5.485
5.490
5.495
5.500
5.505
nu
clear ch
arge rad
ius (fm
)
10
15
20
25
30
40
50
60
80
100
5.460
5.465
5.470
5.475
5.480
5.485
5.490
5.495
5.500
5.505
202 204 205 206 207 208
nu
cle
ar
ch
arg
e r
ad
ius
(fm
)Odd-even staggering of Pb isotopes
(extended spectrum)Odd-even staggering of Pb isotopes
(extended spectrum)
Sakakihara et al. (2001)
Analytical mass fractionation Odd-even staggering and
instrumental bias
Analytical mass fractionation Odd-even staggering and
instrumental bias
Blichert-Toft et al. (2003) Doucelance et al. (2001)
PbPb
ConclusionsConclusions
• The number of nucleosynthetic components needs to be more rigorously evaluated
• The strength of the nuclear field shift effect w.r.t. nucleosynthetic anomalies still unclear
• Odd-even staggering of nuclear properties is ubiquitous and its cause is multiple: neutron cross-sections, nuclear field radii, and masses
MoMo
SmSm
100
1000
10000
100000
T1
/2
4.85
4.90
4.95
5.00
5.05
5.10
5.15
nu
clear charg
e radiu
s (fm)
5
10
15
20
25
30
40
50
60
80
100
SmSm
-800
-600
-400
-200
0
200
400
600
800
1000
1200
e Sm
i
GRZ-1
15555
Gladstone
Homestead
Peace
Ucera
Indarch
Orgueil
Mighei
Murray
Allende
Grosnaja
Mokoia
Carlson et al. (2007)
r-process nuclide abundancesr-process nuclide abundances
Arnould et al. (2007)
MoMo
100
1000
10000
92Mo(p) 94Mo(p) 95Mo(s,r) 96Mo(s) 97Mo(s,r) 98Mo(s,r) 100Mo(r)
T1
/2
4.25
4.30
4.35
4.40
4.45
4.50
nu
clear charg
e radiu
s (fm)
10
15
20
25
30
40
50
60
80
100
Series11
Mo isotopic anomalies in carbonaceous chondritesMo isotopic anomalies in carbonaceous chondrites
Orgueil
Allende
Dauphas et al. (2002)
Yin et al. (2002)
Meteorites vs pre-solar grainsMeteorites vs pre-solar grains
Dauphas et al. (2004)
Nicolussi et al. (1998)
MoMo
100
1000
10000
92Mo(p) 94Mo(p) 95Mo(s,r) 96Mo(s) 97Mo(s,r) 98Mo(s,r) 100Mo(r)
T1
/2
4.25
4.30
4.35
4.40
4.45
4.50
nu
clear ch
arge rad
ius (fm
)
10
15
20
25
30
40
50
60
80
100
Series11
SiC: Pellin et al. (1999)
Os: normalization to 189 is risky too
100
1000
10000
184Os(p) 186Os(s) 187Os(s,p) 188Os(r,s) 189Os(r) 190Os(r,s) 192Os(r)
T1/
2
5.33
5.34
5.35
5.36
5.37
5.38
5.39
5.4
5.41
5.42
nu
clear chag
e radiu
s
10
15
20
25
30
40
50
60
80
100
SmSm
100
1000
10000
100000
T1
/2
4.85
4.90
4.95
5.00
5.05
5.10
5.15
nu
clear charg
e radiu
s (fm
)
5
10
15
20
25
30
40
50
60
80
100
Nd may help telling NFS from (s,r) mixingNd may help telling NFS from (s,r) mixing
10
100
1000
10000
142Nd(s) 143Nd(r,s) 144Nd(s,r) 145Nd(r,s) 146Nd(s,r) 148Nd(r,s) 150Nd(r)
T1
/2
4.80
4.85
4.90
4.95
5.00
5.05
5.10
nu
clear charg
e radiu
s (fm)
5
10
15
20
25
30
40
50
60
80
100
0.612
0.614
0.616
0.618
0.620
0.622
0.624
0.626
0.628
4.535 4.540 4.545 4.550 4.555 4.560 4.565 4.570 4.575
Age (Ga)
20
7P
b*/
20
6P
b*
The devil is in the details: precision is not the main issue of U-Pb
chronology but odd-even staggering
The devil is in the details: precision is not the main issue of U-Pb
chronology but odd-even staggering
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