36,170 research outputs found
Time-resolved multi-mass ion imaging: femtosecond UV-VUV pump-probe spectroscopy with the PImMS camera
The Pixel-Imaging Mass Spectrometry (PImMS) camera allows for 3D charged
particle imaging measurements, in which the particle time-of-flight is recorded
along with position. Coupling the PImMS camera to an ultrafast
pump-probe velocity-map imaging spectroscopy apparatus therefore provides a
route to time-resolved multi-mass ion imaging, with both high count rates and
large dynamic range, thus allowing for rapid measurements of complex
photofragmentation dynamics. Furthermore, the use of vacuum ultraviolet
wavelengths for the probe pulse allows for an enhanced observation window for
the study of excited state molecular dynamics in small polyatomic molecules
having relatively high ionization potentials. Herein, preliminary time-resolved
multi-mass imaging results from CFI photolysis are presented. The
experiments utilized femtosecond UV and VUV (160.8~nm and 267~nm) pump and
probe laser pulses in order to demonstrate and explore this new time-resolved
experimental ion imaging configuration. The data indicates the depth and power
of this measurement modality, with a range of photofragments readily observed,
and many indications of complex underlying wavepacket dynamics on the excited
state(s) prepared
The Infrared Camera (IRC) for AKARI - Design and Imaging Performance
The Infrared Camera (IRC) is one of two focal-plane instruments on the AKARI
satellite. It is designed for wide-field deep imaging and low-resolution
spectroscopy in the near- to mid-infrared (1.8--26.5um) in the pointed
observation mode of AKARI. IRC is also operated in the survey mode to make an
all-sky survey at 9 and 18um. It comprises three channels. The NIR channel
(1.8--5.5um) employs a 512 x 412 InSb array, whereas both the MIR-S
(4.6--13.4um) and MIR-L (12.6--26.5um) channels use 256 x 256 Si:As impurity
band conduction arrays. Each of the three channels has a field-of-view of about
10' x 10' and are operated simultaneously. The NIR and MIR-S share the same
field-of-view by virtue of a beam splitter. The MIR-L observes the sky about
$25' away from the NIR/MIR-S field-of-view. IRC gives us deep insights into the
formation and evolution of galaxies, the evolution of planetary disks, the
process of star-formation, the properties of interstellar matter under various
physical conditions, and the nature and evolution of solar system objects. The
in-flight performance of IRC has been confirmed to be in agreement with the
pre-flight expectation. This paper summarizes the design and the in-flight
operation and imaging performance of IRC.Comment: Publications of the Astronomical Society of Japan, in pres
ATLAS 1: Encountering Planet Earth
Several NASA science programs examine the dynamic balance of sunlight, atmosphere, water, land, and life that governs Earth's environment. Among these is a series of Space Shuttle-Spacelab missions, named the Atmospheric Laboratory for Applications and Science (ATLAS). During the ATLAS missions, international teams of scientists representing many disciplines combine their expertise to seek answers to complex questions about the atmospheric and solar conditions that sustain life on Earth. The ATLAS program specifically investigates how Earth's middle atmosphere and upper atmospheres and climate are affected by both the Sun and by products of industrial and agricultural activities on Earth
Digest of celestial X-ray missions and experiments
Information on instruments, the platforms that carried them, and the data they gathered is presented. Instrument selection was confined to detectors operating in the 0.20 to 300 keV range. Included are brief descriptions of the spacecraft, experiment packages and missions. Cross-referenced indexes are provided for types of instruments, energy ranges, time spans covered, positional catalogs and observational catalogs. Data sets from these experiments (NSSDC) are described
Space life sciences: A status report
The scientific research and supporting technology development conducted in the Space Life Sciences Program is described. Accomplishments of the past year are highlighted. Plans for future activities are outlined. Some specific areas of study include the following: Crew health and safety; What happens to humans in space; Gravity, life, and space; Sustenance in space; Life and planet Earth; Life in the Universe; Promoting good science and good will; Building a future for the space life sciences; and Benefits of space life sciences research
Aerospace medicine and Biology: A continuing bibliography with indexes, supplement 177
This bibliography lists 112 reports, articles, and other documents introduced into the NASA scientific and technical information system in January 1978
Aerospace Medicine and Biology: A continuing bibliography with indexes (supplement 141)
This special bibliography lists 267 reports, articles, and other documents introduced into the NASA scientific and technical information system in April 1975
Overcoming the Challenges Associated with Image-based Mapping of Small Bodies in Preparation for the OSIRIS-REx Mission to (101955) Bennu
The OSIRIS-REx Asteroid Sample Return Mission is the third mission in NASA's
New Frontiers Program and is the first U.S. mission to return samples from an
asteroid to Earth. The most important decision ahead of the OSIRIS-REx team is
the selection of a prime sample-site on the surface of asteroid (101955) Bennu.
Mission success hinges on identifying a site that is safe and has regolith that
can readily be ingested by the spacecraft's sampling mechanism. To inform this
mission-critical decision, the surface of Bennu is mapped using the OSIRIS-REx
Camera Suite and the images are used to develop several foundational data
products. Acquiring the necessary inputs to these data products requires
observational strategies that are defined specifically to overcome the
challenges associated with mapping a small irregular body. We present these
strategies in the context of assessing candidate sample-sites at Bennu
according to a framework of decisions regarding the relative safety,
sampleability, and scientific value across the asteroid's surface. To create
data products that aid these assessments, we describe the best practices
developed by the OSIRIS-REx team for image-based mapping of irregular small
bodies. We emphasize the importance of using 3D shape models and the ability to
work in body-fixed rectangular coordinates when dealing with planetary surfaces
that cannot be uniquely addressed by body-fixed latitude and longitude.Comment: 31 pages, 10 figures, 2 table
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