Search for supernova-produced 60Fe in a marine sediment.
An 60Fe peak in a deep-sea FeMn crust has been interpreted as due to the signature left by the ejecta of a supernova explosion close to the solar system 2.8+/-0.4 Myr ago [Knie, Phys. Rev. Lett. 93, 171103 (2004)10.1103/PhysRevLett.93.171103]. In an attempt to confirm this interpretation with better time resolution and obtain a more direct flux estimate, we measured 60Fe concentrations along a dated marine sediment. We find no 60Fe peak at the expected level from 1.7 to 3.2 Myr ago. Possible causes for the discrepancy are discussed.
Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM) IN2P3/CNRS, Université Paris Sud, Bâtiment 108, Orsay, France.
C
C
Fitoussi
G M
GM
Raisbeck
K
K
Knie
G
G
Korschinek
T
T
Faestermann
S
S
Goriely
D
D
Lunney
M
M
Poutivtsev
G
G
Rugel
C
C
Waelbroeck
A
A
Wallner