|
He and Ne Ages of Large Presolar Silicon Carbide Grains: Solving the Recoil Problem
Ulrich
Ott A F,
Philipp R.
Heck B C,
Frank
Gyngard D,
Rainer
Wieler B,
Frédéric
Wrobel E,
Sachiko
Amari D,
Ernst
Zinner D
A
Max-Planck-Institute for Chemistry, Joh.-J.-Becher-Weg 27, D-55128 Mainz, Germany
B
Institute of Isotope Geology and Mineral Resources, ETH Zürich, CH-8092 Zürich, Switzerland
C
Chicago Center for Cosmochemistry, Department of the Geophysical Sciences, The University of Chicago, Chicago, IL, USA
D
Laboratory for Space Sciences and the Physics Department, Washington University, St. Louis, MO 63130, USA
E
Institut d’Electronique du Sud, Université de Montpellier 2, F-34095 Montpellier, France
F
Corresponding author. Email: ott@mpch-mainz.mpg.de
|  |
|
Publications of the Astronomical Society of Australia 26(3) 297–302 http://dx.doi.org/10.1071/AS08039
Submitted: 15 November 2008
Accepted: 16 February 2009
Published online: 10 September 2009
Abstract
Knowledge about the age of presolar grains provides important insights into Galactic chemical evolution and the dynamics of grain formation and destruction processes in the Galaxy. Determination from the abundance of cosmic ray interaction products is straightforward, but in the past has suffered from uncertainties in correcting for recoil losses of spallation products. The problem is less serious in a class of large (tens of μm) grains. We describe the correction procedure and summarise results for He and Ne ages of presolar SiC ‘Jumbo’ grains that range from close to zero to ~850 Myr, with the majority being less than 200 Myr. We also discuss the possibility of extending our approach to the majority of smaller SiC grains and explore possible contributions from trapping of cosmic rays.
Keywords:
circumstellar matter — stars: AGB — ISM: kinematic and dynamics — cosmic rays
|
|
|
 |
Subscriber Login |
 |
|
Early Alert
Connect with us
