Results 41 to 50 of about 307 (107)
Magmatic dyke systems of the South Shetland Islands volcanic arc (West Antarctica): reflections of the geodynamic history [PDF]
, 2005 The Antarctic Peninsula forms part of a magmatic arc at least since Jurassic times. Magmatic dykes are essential elements of such arcs and intrude along zones of instability.
Kraus, Stefan
core +1 more source
The CAI Database: 26Al–26Mg Isotope Systematics
The Astrophysical Journal Supplement SeriesWe present a publicly available calcium–aluminum-rich inclusion (CAI) database that focuses on the initial ^26 Al/ ^27 Al _0 ratio in CAIs, designed in a way that researchers in cosmochemistry and astrophysics may find useful.
Emilie T. Dunham +7 more
doaj +1 more source
Geochimica et Cosmochimica Acta, 2016 AbstractThe 53Mn–53Cr decay system, in which 53Mn decays to 53Cr (t1/2=3.7Ma) has been widely used to construct 53Cr/52Cr vs. 55Mn/52Cr isochrons and thus determine relative ages of early solar system objects or events, assuming that the initial Cr isotopic ratio, (53Cr/52Cr)o, equals (53Mn/52Cr)o.
Posner, Esther S. +2 more
openaire +1 more source
Scientific returns from a program of space missions to comets [PDF]
, 1979 A program of cometary missions is proposed. The nature and size of interstellar dust, its origin and evolution; identification of new interstellar molecules; clarification of interstellar chemistry; accretion of grains into protosolar cometesimals; role ...
Delsemme, A. H.
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Setting new constraints on the age of the Universe [PDF]
, 2001 There are three independent techniques for determining the age of the Universe: via cosmochronology of long-lived radioactive nuclei, via stellar modelling and population synthesis of the oldest stellar populations, and, most recently, via the precision ...
Ferreras, I. +5 more
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Half-lives of radionuclides used in nuclear geochronology and cosmochronology (evaluated data)
, 2001 Evaluated half-life values are given for the radionuclides sup 2 sup 6 Al, sup 4 sup 0 K, sup 5 sup 3 Mn, sup 6 sup 0 Fe, sup 8 sup 7 Rb, sup 9 sup 3 Zr, sup 9 sup 8 Tc, sup 1 sup 0 sup 7 Pd, sup 1 sup 2 sup 9 I, sup 1 sup 3 sup 5 Cs, sup 1 sup 4 sup 6 ...
Chechev, V P
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Ther‐Process in the Neutrino Winds of Core‐Collapse Supernovae and U‐Th Cosmochronology
The Astrophysical Journal, 2002 The discovery of the second highly $r$-process-enhanced, extremely metal-poor star, CS 31082-001 ([Fe/H] $= -2.9$) has provided a powerful new tool for age determination, by virtue of the detection and measurement of the radioactive species uranium and thorium.
Wanajo, Shinya +4 more
openaire +2 more sources
Influence of nuclear physics inputs and astrophysical conditions on the Th/U chronometer
, 2009 The productions of thorium and uranium are key ingredients in r-process nucleo-cosmochronology. With the combination of improved nuclear and stellar data, we have made a detailed investigation of the r-process abundance pattern in the very metal-poor ...
Sun B. +5 more
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Theoretical and experimental lifetime determination in singly ionized neodymium (Nd II)
, 2003 peer reviewedRadiative lifetime measurements were performed with time-resolved laser-induced fluorescence techniques for 24 levels of Nd II in the energy range 20 500- 32 500 cm(-1). For 17 levels, no previous experimental data exist.
Cowan, R. D. +14 more
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Modelling uncertainty of the Rhenium-Osmium cosmic clock
, 2018 The nuclide 187Re beta-decays to 187Os with a half-life of approximately 41.6 Gyr. The long half-life and simple relation between 187Re and 187Os makes the ratio a good candidate for a cosmic clock.
Svendsen, Øyvind Brynhildsvoll
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