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W.M. Keck Research Laboratory
in Astrochemistry
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The W.M. Keck Research Laboratory in
Astrochemistry located at the University of Hawaii at Manoa is a
state-of-the-art international user facility established in 2010 with the
support of the W.M. Keck Foundation and the University of Hawaii at Manoa. We
invite collaborative proposals catalyzing multidisciplinary research in the
fields of astrochemistry, planetary sciences, astrobiology, material
sciences, and reaction dynamics. Inquiries and proposals (General User Proposal)
shall be sent to Ralf I. Kaiser (ralfk@hawaii.edu)
or to Brant M. Jones (brantmj@hawaii.edu) ; novel research directions are
supported and encouraged. The overall goal of the W.M. Keck Research
Laboratory in Astrochemistry is to unravel the effects of the interaction of
ionizing radiation (charged particles, UVVUV photons) with interstellar and
solar system ices, minerals, and carbonaceous surfaces at temperatures as low
as 4 K and to comprehend the chemical and astrobiological
evolution of the Solar System. This is achieved through an understanding of
the formation of carbon-, hydrogen-, oxygen-, and nitrogen-bearing (CHON)
molecules in ices of, for instance, Kuiper Belt Objects (KBOs)
by reproducing the space environment in a specially designed experimental
setup. KBOs are small planetary bodies orbiting the
sun beyond the planet Neptune, which are considered as the most primitive
objects in the Solar System. A study of KBOs is
important because they resemble natural time capsules at a frozen stage
before life developed on Earth. Our methodology is based on a comparison of
the molecules formed in the experiments with the current composition of KBOs; such approach provides an exceptional potential to
reconstruct the composition of icy Solar System bodies at the time of their
formation billions of years ago. The significance of this project is that our
studies elucidate the origin of biologically relevant molecules and help
unravel the chemical evolution of the Solar System. Since KBOs
are believed to be the main reservoir of short-period comets, which are
considered as delivery systems of biologically important molecules to the
early Earth, our project also brings us closer to the understanding of how
life might have emerged on Earth. |
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To achieve this goal, we established
the interdisciplinary W.M. Keck Laboratory in Astrochemistry comprising
researchers from the UH Department of Chemistry (Ralf Kaiser, John Head), UH
Department of Physics & Astronomy (Klaus Sattler), the UH Institute for
Astronomy (Karen Keech), UH HIGP (Shiv Sharma),
UCLA (David Jewitt), and NASA Goddard (John Cooper). The centerpiece of this
is a novel ultra high vacuum (UHV) surface scattering machine mimicking the
chemical evolution of icy bodies such as KBOs and
icy moons. This experimental setup allows a systematic investigation of the
formation of new species on the molecular level in low temperature ices
and/or silicates/carbonaceous matter by ionizing radiation (solar wind
particles and photons, galactic cosmic rays) over a wide range of parameters
under ultra clean (10-11 torr) conditions at temperatures as low
as 4 K. By analyzing intermediates and products on line and in situ via
infrared, Raman, UV/VIS spectroscopy and time-of-flight/mass spectrometry
utilizing soft ionization (low energy electrons, tunable photoionization),
the formation routes of newly formed molecules can be extracted
quantitatively. Theoretical calculations (John Head; Chemistry) are crucial to
extend the experiments, which can be carried out only at discrete irradiation
wavelengths and kinetic energies of the irradiating particles. These studies
are cross linked with observations of KBOs at Keck
and Subaru telescopes at
The four pillars of multidisciplinary
collaborations within the interdisciplinary W.M. Keck Research Laboratory in
Astrochemistry |
Assembly
drawing (left) and top view (right) of the new surface scattering machine.
Analytical
light sources from the infrared (IR) to the vacuum ultraviolet (VUV) in the
simulation chamber compared to currently operating space probes (left) and
resonant four wave mixing schemes to generate tunable vacuum ultraviolet (VUV)
light in the laboratory; mixing schemes involve gas cells and differentially
pumped, pulsed jet expansions
Reflectron-time-of-flight
(Re-TOF) spectrometer (left) and main chamber (right).
Quadruply
differentially pumped proton (left) and doubly differentially pumped electron
source (right).
Tunable
UVVUV laser system (left) and free jet expansion chamber for four wave mixing
scheme (right).
Tunable
CW UVVUV source (left) and resulting high and low resolution spectra (right).
Overview
of W.M. Keck Research Laboratory in Astrochemistry.
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irradiation
sources |
analytical
probes |
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tunable UVVUV
light (continuous mode) |
Infrared
spectroscopy |
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electron beam (tunable
energies) |
Raman
spectroscopy |
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charged
particle beam (tunable
energy) |
UVVIS/UVVUV
spectroscopy |
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tunable UVVUV
light (pulsed mode) |
RGA-QMS |
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Re-TOF |
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Kelvin probe |
