Transcript Short-lived radioisotopes: A cosmochemical connection between star and planet formation Launch of COROT Eric Gaidos1,3 Jonathan Williams2,3 Nick Moskovitz2 Daniel Rogerrs4 1Department of Geology & Geophysics 2Institute for Astronomy 3NASA Astrobiology Institute 4Department.

Short-lived radioisotopes:
A cosmochemical connection
between
star and planet formation
Launch of COROT
Eric Gaidos1,3
Jonathan Williams2,3
Nick Moskovitz2
Daniel Rogerrs4
1Department
of Geology & Geophysics
2Institute for Astronomy
3NASA Astrobiology Institute
4Department of Physics & Astronomy
University of Hawaii at Manoa
From Stars to Planets
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Evidence for live 26Al in the early Solar System
Armstrong et al. (1984)
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Early (<2 Myr) differentiation of some meteorite parent bodies
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Markowski
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et al. (2006)
Evidence for the homogeneity of 26Al
Thrane et al. (2006)
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Absence of 60Fe in iron meteorite parent bodies?
Bizzarro et al. (2006)
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Contribution to 26Al by Wolf-Rayet winds
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26Al
60Fe
Meynet & Maeder (2005)
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Overlapping time scales
Half life of 26Al
0.72 Myr
Massive star lifetime
>3 Myr
Protostar and disk lifetime
1-5 Myr
Cluster dispersal time
1-10 Myr
Accretion time scale
1-10 Myr
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N-body simulations of a
9000-star cluster containing a 60 solar-mass (O3) star
and ~270 solar mass (0.9-1.1) stars
t = 3 Myr
t=0
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N = 9000
Williams & Gaidos, in prep.
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Cumulative distribution of relative 26Al inventories
0.1X
1X
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10X
Thermal histories of 3-km planetesimals
with Solar, 0.1X, and 10X 26Al
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Fractional Mass Experiencing Temperatures < 700K
1
1X
0.1X
10X
0.8
0.6
0.4
0.2
0
0
2
4
6
8
10
12
Accretion Timescale [Myr]
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14
16
18
20
Less dehydration: Ocean worlds?
Leger et al. (2004)
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Disk injection scenario
solar system value; 26Al/27Al = 5.85 × 10-5
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Single O3 (60 solar-mass star) in 500 star
cluster
Plummer sphere with specified core
radius and virial parameter ≥0.5 reflecting
gas loss (Bastian & Goodwin 2006)
Simulation stopped at 3.8 Myr
Yield of 26Al in wind from Limongi &
Chieffi (2006)
Injection efficiency of 100%; no decay
during time of flight
Mass fraction of 26Al calculated according
to Looney et al. (2006):
time of flight of ejecta
M i e t ln 2 /1 / 2
Xi  f
4D 2 ss
mass of isotope in ejecta
injection efficiency
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surface density of SS
distance from SS to progenitor
g = 0.9
g = 0.5
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Denizens of a low 26Al world....
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