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W. M. Keck Cosmochemistry Laboratory in Hawaii

The W. M. Keck Cosmochemistry Laboratory supports interdisciplinary research into the origin of the solar system through detailed studies of a variety of materials including meteorites, interplanetary dust particles (IDPs), and samples returned by NASA missions.

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Our broad research themes:
  - Presolar grains and comet dust,
  - Mixing of reservoirs and processing of materials in the early solar system,
  - Early solar system chronology by measuring decay products of short-lived radionuclides.
The centerpiece of the lab is a new Cameca ims 1280 ion microprobe, installed in 2006.  

The Cameca ims 1280 (shown above, left, and on the right in schematic format) is the newest incarnation of the large-geometry Cameca ion probe (Conty, 1990). It uses a new generation of electronics to control the voltages in the primary-ion column and secondary-ion mass spectrometer. It has improved magnet control, including an improved Hall probe system and a new NMR system. It  as computer control of all slits and apertures, new computer routines to improve reproducibility, and improved ion detectors. These new features give the 1280 better performance than earlier machines.

We will upgrade this highly capable instrument with additional state-of-the-art technologies to address the unique challenges of research on early solar-system materials. We will add a secondary-electron detector to aid in locating tiny grains for analysis. The secondary-electron image in the ion microprobe can be directly correlated with the secondary-electron image from an SEM. To help precisely position the sample under the primary beam during automated analyses and to facilitate using sample locations determined by an automated system on the SEM, we will add optical encoders to the sample stage. In collaboration with Prof. Yurimoto of Hokkaido Univer
sity, Japan, we will add a new type of two-dimensional, solid-state detector called SCAPS (Nagashima et al., 2001; Yurimoto et al., 2003). Kazuhide Nagashima, a member of our research team, is a co-developer of this unique detector. The SCAPS detector will permit direct ion imaging of fine-grained samples and will permit identification of isotopically or chemically anomalous grains at a spatial resolution of a few tenths of a micron (Nagashima et al., 2004; Kobayashi et al., 2005).  
Origin of the Solar System
We will use the Cameca ims 1280 and associated equipment to investigate the origin of the solar system. The research can be thought of as consisting of three basic types of investigations: 1) Studies of the raw materials that were the building blocks for the solar system, including presolar grains from meteorites, interplanetary dust particles, and comet samples returned by the Stardust mission. 2) Studies of the timing of events during the formation of the solar system. Chronology will be investigated through studies of short-lived radionuclides. 3) Studies of early solar system processes, which we will investigate through measurements of chemical compositions, trace-element abundances, isotopic fractionations, and the unique variations exhibited by oxygen isotopes.

In addition to the laboratory work, our studies will have strong interdisciplinary collaborations with the astronomers and astrophysicists at the
Institute for Astronomy at the University of Hawaii and around the world, and with the University of Hawaii Astrobiology Institute.
The people responsible for the success of the W. M. Keck Cosmochemistry Laboratory

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