J/ApJ/909/8 Molybdenum isotopes in meteorites (Stephan+, 2021)
Molybdenum isotope dichotomy in meteorites caused by s-process variability.
Stephan T., Davis A.M.
<Astrophys. J., 909, 8 (2021)>
=2021ApJ...909....8S 2021ApJ...909....8S
ADC_Keywords: Meteorites; Abundances
Keywords: Meteorites ; Circumstellar grains ; S-process ; R-process ;
P-process ; Nucleosynthesis ; Solar system formation ;
Isotopic abundances
Abstract:
Molybdenum isotopes measured in most individual presolar silicon
carbide grains are dominated by s-process contributions from the
helium intershells of asymptotic giant branch (AGB) stars. The much
smaller isotopic variations in molybdenum in meteorites and their
components are largely controlled by s-process enrichments or
depletions relative to terrestrial composition but lie along two
parallel s-process mixing lines separated by what has been suggested
to be an r-process contribution. The two mixing lines are populated by
carbonaceous-chondrite- and noncarbonaceous-chondrite-related
meteorites (CC and NC groups, respectively). We have compared
molybdenum isotopic data for presolar grains with those from
meteorites and renormalized the meteorite data in a way that is
consistent with s-, r-, and p-process contributions observed in
presolar SiC grains. The results indicate that (1) there seems to be a
fixed ratio between p- and r-process contributions in all data,
(2) the dichotomy in molybdenum isotopes between the CC and NC groups
can be explained by variations in the isotope makeup of the s-process
contribution to the meteoritic samples, (3) this variability is
similar to the variations in s-process molybdenum from different AGB
stars deduced from presolar grain analyses, and (4) the larger range
of isotopic compositions found in refractory inclusions is also
consistent with s-process isotope variability.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 153 269 Meteorite molybdenum isotope data renormalized
to ε98Mo96/ε92Mo96=0.256
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See also:
J/MNRAS/418/284 : s-process in low-metallicity stars. II. (Bisterzo+, 2011)
J/ApJ/743/L23 : 48Ca heterogeneity in differentiated meteorites (Chen+, 2011)
J/ApJ/758/45 : Isotopic Sr abundances in meteorites (Moynier+, 2012)
J/ApJ/758/59 : Nickel isotopes in meteorites (Steele+, 2012)
J/ApJ/787/10 : Solar s-process contributions with GCE model (Bisterzo+, 2014)
J/ApJ/854/18 : Nucleosynthesis of p nuclides (Travaglio+, 2018)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1 I1 --- Group [1/3] Meteorite group (1)
3- 25 A23 --- Subgroup Subgroup
27- 46 A20 --- Type Type (2)
48- 72 A25 --- Sample Meteorite/Sample (2)
74- 79 F6.2 --- eps92Mo96 [-52.03/19.98] Molybdenum-92 isotopic data
81- 84 F4.2 --- e_eps92Mo96 [0.02/2.1] 1σ uncertainty in eps92Mo96
86- 91 F6.2 --- eps94Mo96 [-50.92/18.92] Molybdenum-94 isotopic data
93- 96 F4.2 --- e_eps94Mo96 [0.02/1.9] 1σ uncertainty in eps94Mo96
98- 103 F6.2 --- eps95Mo96 [-31.47/12.66] Molybdenum-95 isotopic data
105- 108 F4.2 --- e_eps95Mo96 [0.01/1.1] 1σ uncertainty in eps95Mo96
110- 115 F6.2 --- eps97Mo96 [-27.43/10.35] Molybdenum-97 isotopic data
117- 120 F4.2 --- e_eps97Mo96 [0/0.7] 1σ uncertainty in eps97Mo96
122- 127 F6.2 --- eps98Mo96 [-13.3/5.11] Molybdenum-98 isotopic data
129- 132 F4.2 --- e_eps98Mo96 [0/0.5] 1σ uncertainty in eps98Mo96
134- 139 F6.2 --- eps100Mo96 [-51.73/19.8] Molybdenum-100 isotopic data
141- 144 F4.2 --- e_eps100Mo96 [0.01/2.2] 1σ uncertainty in
eps100Mo96
146- 151 A6 --- Ref Reference (3)
153 A1 --- Notes Notes (4)
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Note (1): Meteorite grouping codes as follows:
1 = Carbonaceous-Chondrite-Related (CC) Meteorites;
2 = Noncarbonaceous-Chondrite-Related (NC) Meteorites;
3 = Calcium-aluminum-rich inclusions (CAIs).
Note (2): Meteorite names and types, which are in some cases different from
those in the original publications cited here, are given according to
the Meteoritical Bulletin Database (http://www.lpi.usra.edu/meteor/).
For detailed sample descriptions, please refer to the original
literature. CAIs are subdivided into unfractionated and fractionated
groups according to Brennecka+ (2013PNAS..11017241B 2013PNAS..11017241B).
Uncertainties are 1σ.
Note (3): References as follows:
Dau02a = Dauphas et al. (2002ApJ...565..640D 2002ApJ...565..640D);
Dau02b = Dauphas et al. (2002ApJ...569L.139D 2002ApJ...569L.139D);
Bur11 = Burkhardt et al. (2011E&PSL.312..390B 2011E&PSL.312..390B);
Bur12 = Burkhardt et al. (2012E&PSL.357..298B 2012E&PSL.357..298B);
Bre13 = Brennecka et al. (2013PNAS..11017241B 2013PNAS..11017241B);
Bur14 = Burkhardt et al. (2014E&PSL.391..201B 2014E&PSL.391..201B);
Bud16 = Budde et al. (2016E&PSL.454..293B 2016E&PSL.454..293B);
Kru17 = Kruijer et al. (2017PNAS..114.6712K 2017PNAS..114.6712K);
Ren17 = Render et al. (2017, Geochem. Perspect. Lett. 3, 170);
Wor17 = Worsham et al. (2017E&PSL.467..157W 2017E&PSL.467..157W);
Ber18 = Bermingham et al. (2018E&PSL.487..221B 2018E&PSL.487..221B);
Sho18 = Shollenberger et al. (2018GeCoA.228...62S 2018GeCoA.228...62S);
Bud18 = Budde et al. (2018GeCoA.222..284B 2018GeCoA.222..284B);
Bud19 = Budde et al. (2019NatAs...3..736B 2019NatAs...3..736B);
Wor19 = Worsham et al. (2019E&PSL.521..103W 2019E&PSL.521..103W);
Yok19 = Yokoyama et al. (2019ApJ...883...62Y 2019ApJ...883...62Y);
Bre20 = Brennecka et al. (2020Sci...370..837B 2020Sci...370..837B);
Hop20 = Hopp et al. (2020E&PSL.53416065H 2020E&PSL.53416065H);
Spi20 = Spitzer et al. (2020ApJ...898L...2S 2020ApJ...898L...2S).
Note (4): Notes on individual values as follows:
a = Platinum data for CRE correction were taken from
Kruijer+ (2017PNAS..114.6712K 2017PNAS..114.6712K);
b = In the original publication (Render+ 2017, Geochem. Perspect. Lett. 3,
170), EET 87746 (EH4 enstatite chondrite) was incorrectly reported
as EET 87747 (EH4), which would instead be a CR2 carbonaceous chondrite;
c = Sombrerete was initially attributed to the CC meteorite group
(Worsham+ 2017E&PSL.467..157W 2017E&PSL.467..157W) but is here counted as a NC meteorite
like all other IAB iron meteorites. Due to the large errors of this
single analysis, this has no significant impact on any results or
conclusions;
d = CAI types for CAIs analyzed by Brennecka+ (2013PNAS..11017241B 2013PNAS..11017241B) were
provided by Shollenberger+ (2018GeCoA.228...62S 2018GeCoA.228...62S).
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 05-Aug-2022