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Seminatrix, S. pygaea
Number of Pages: 5Integrative BiologyGeological Science
Solar System Processes Underlying Planetary Formation, Geodynamics, and the Georeactor
Only three processes, operant during the formation of the Solar System, are
responsible for the diversity of matter in the Solar System and are directly
responsible for planetary internal-structures, including planetocentric nuclear
fission reactors, and for dynamical processes, including and especially,
geodynamics. These processes are: (i) Low-pressure, low-temperature
condensation from solar matter in the remote reaches of the Solar System or in
the interstellar medium; (ii) High-pressure, high-temperature condensation from
solar matter associated with planetary-formation by raining out from the
interiors of giant-gaseous protoplanets, and; (iii) Stripping of the primordial
volatile components from the inner portion of the Solar System by super-intense
solar wind associated with T-Tauri phase mass-ejections, presumably during the
thermonuclear ignition of the Sun. As described herein, these processes lead
logically, in a causally related manner, to a coherent vision of planetary
formation with profound implications including, but not limited to, (a) Earth
formation as a giant gaseous Jupiter-like planet with vast amounts of stored
energy of protoplanetary compression in its rock-plus-alloy kernel; (b) Removal
of approximately 300 Earth-masses of primordial gases from the Earth, which
began Earth's decompression process, making available the stored energy of
protoplanetary compression for driving geodynamic processes, which I have
described by the new whole-Earth decompression dynamics and which is
responsible for emplacing heat at the mantle-crust-interface at the base of the
crust through the process I have described, called mantle decompression
thermal-tsunami; and, (c)Uranium accumulations at the planetary centers capable
of self-sustained nuclear fission chain reactions.Comment: Invited paper for the Special Issue of Earth, Moon and Planets
entitled Neutrino Geophysics Added final corrections for publicatio
Inverse beta decay reaction in Th and U fission antineutrino flux
Energy spectra of antineutrinos coming from Th and U
neutron-induced fission are calculated, relevant inverse beta decay
positron spectra and total cross sections are
found. This study is stimulated by a hypothesis that a self-sustained nuclear
chain reaction is burning at the center of the Earth ("Georeactor"). The
Georeactor, according to the author of this idea, provides energy necessary to
sustain the Earth's magnetic field. The Georeactor's nuclear fuel is U
and, probably, Th and U. Results of present study may appear to
be useful in future experiments aimed to test the Georector hypothesis and to
estimate its fuel components as a part of developments in geophysics and
astrophysics based on observations of low energy antineutrinos in Nature.Comment: 6 pages in LaTeX and 2 ps figures. Submitted to Physics of Atomic
Nucle
Neutrino Geophysics at Baksan I: Possible Detection of Georeactor Antineutrinos
J.M. Herndon in 90-s proposed a natural nuclear fission georeactor at the
center of the Earth with a power output of 3-10 TW as an energy source to
sustain the Earth magnetic field. R.S. Raghavan in 2002 y. pointed out that
under certain condition antineutrinos generated in georeactor can be detected
using massive scintillation detectors. We consider the underground Baksan
Neutrino Observatory (4800 m.w.e.) as a possible site for developments in
Geoneutrino physics. Here the intrinsic background level of less than one
event/year in a liquid scintillation ~1000 target ton detector can be achieved
and the main source of background is the antineutrino flux from power reactors.
We find that this flux is ~10 times lower than at KamLAND detector site and two
times lower than at Gran Sasso laboratory and thus at Baksan the georeactor
hypothesis can be conclusively tested. We also discuss possible search for
composition of georector burning nuclear fuel by analysis of the antineutrino
energy spectrum.Comment: 7 pages in LaTeX, 3 PS figures, Submitted to Physics of Atomic Nucle
Heat flow of the Earth and resonant capture of solar 57-Fe axions
In a very conservative approach, supposing that total heat flow of the Earth
is exclusively due to resonant capture inside the Earth of axions, emitted by
57-Fe nuclei on Sun, we obtain limit on mass of hadronic axion: m_a<1.8 keV.
Taking into account release of heat from decays of 40-K, 232-Th, 238-U inside
the Earth, this estimation could be improved to the value: m_a<1.6 keV. Both
the values are less restrictive than limits set in devoted experiments to
search for 57-Fe axions (m_a<216-745 eV), but are much better than limits
obtained in experiments with 83-Kr (m_a<5.5 keV) and 7-Li (m_a<13.9-32 keV).Comment: 8 page
Effect of aerosols and NO<sub>2</sub> concentration on ultraviolet actinic flux near Mexico City during MILAGRO: measurements and model calculations
Urban air pollution absorbs and scatters solar ultraviolet (UV) radiation, and thus has a potentially large effect on tropospheric photochemical rates. We present the first detailed comparison between actinic fluxes (AF) in the wavelength range 330â420 nm measured in highly polluted conditions and simulated with the Tropospheric Ultraviolet-Visible (TUV) model. Measurements were made during the MILAGRO campaign near Mexico City in March 2006, at a ground-based station near Mexico City (the T1 supersite) and from the NSF/NCAR C-130 aircraft. At the surface, measured AF values are typically smaller than the model by up to 25% in the morning, 10% at noon, and 40% in the afternoon, for pollution-free and cloud-free conditions. When measurements of PBL height, NO<sub>2</sub> concentration and aerosols optical properties are included in the model, the agreement improves to within ±10% in the morning and afternoon, and ±3% at noon. Based on daily averages, aerosols account for 68% and NO<sub>2</sub> for 25% of AF reductions observed at the surface. Several overpasses from the C-130 aircraft provided the opportunity to examine the AF perturbations aloft, and also show better agreement with the model when aerosol and NO<sub>2</sub> effects are included above and below the flight altitude. TUV model simulations show that the vertical structure of the actinic flux is sensitive to the choice of the aerosol single scattering albedo (SSA) at UV wavelengths. Typically, aerosols enhance AF above the PBL and reduce AF near the surface. However, for highly scattering aerosols (SSA > 0.95), enhancements can penetrate well into the PBL, while for strongly absorbing aerosols (SSA < 0.6) reductions in AF are computed in the free troposphere as well as in the PBL. Additional measurements of the SSA at these wavelengths are needed to better constrain the effect of aerosols on the vertical structure of the AF
A geoneutrino experiment at Homestake
A significant fraction of the 44TW of heat dissipation from the Earth's
interior is believed to originate from the decays of terrestrial uranium and
thorium. The only estimates of this radiogenic heat, which is the driving force
for mantle convection, come from Earth models based on meteorites, and have
large systematic errors. The detection of electron antineutrinos produced by
these uranium and thorium decays would allow a more direct measure of the total
uranium and thorium content, and hence radiogenic heat production in the Earth.
We discuss the prospect of building an electron antineutrino detector
approximately 700m^3 in size in the Homestake mine at the 4850' level. This
would allow us to make a measurement of the total uranium and thorium content
with a statistical error less than the systematic error from our current
knowledge of neutrino oscillation parameters. It would also allow us to test
the hypothesis of a naturally occurring nuclear reactor at the center of the
Earth.Comment: proceedings for Neutrino Sciences 2005, submitted to Earth, Moon, and
Planet
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Application of Gauss's theorem to quantify localized surface emissions from airborne measurements of wind and trace gases
Airborne estimates of greenhouse gas emissions are becoming more
prevalent with the advent of rapid commercial development of trace gas
instrumentation featuring increased measurement accuracy, precision, and
frequency, and the swelling interest in the verification of current emission
inventories. Multiple airborne studies have indicated that emission
inventories may underestimate some hydrocarbon emission sources in USÂ oil-
and gas-producing basins. Consequently, a proper assessment of the accuracy
of these airborne methods is crucial to interpreting the meaning of such
discrepancies. We present a new method of sampling surface sources of any
trace gas for which fast and precise measurements can be made and apply it to
methane, ethane, and carbon dioxide on spatial scales of ââŒ 1000âŻm,
where consecutive loops are flown around a targeted source region at
multiple altitudes. Using Reynolds decomposition for the scalar
concentrations, along with Gauss's theorem, we show that the method
accurately accounts for the smaller-scale turbulent dispersion of the local
plume, which is often ignored in other average mass balance methods. With
the help of large eddy simulations (LES) we further show how the circling
radius can be optimized for the micrometeorological conditions encountered
during any flight. Furthermore, by sampling controlled releases of methane
and ethane on the ground we can ascertain that the accuracy of the method, in
appropriate meteorological conditions, is often better than 10âŻ%, with
limits of detection below 5âŻkgâŻhâ1 for both methane and ethane. Because of the FAA-mandated minimum flight safe altitude of 150âŻm, placement of the aircraft is critical to preventing a large portion of the emission plume from flowing underneath the lowest aircraft sampling altitude, which is generally the leading source of uncertainty in these measurements. Finally, we show how the accuracy of the method is strongly dependent on the number of sampling loops and/or time spent sampling the source plume
Using Observations and Source-Specific Model Tracers to Characterize Pollutant Transport During FRAPPE and DISCOVER-AQ
Transport is a key parameter in air quality research and plays a dominant role in the Colorado Northern Front Range Metropolitan Area (NFRMA), where terrain-induced flows and recirculation patterns can lead to vigorous mixing of different emission sources. To assess different transport processes and their connection to air quality in the NFRMA during the FRAPP and DISCOVER-AQ campaigns in summer 2014, we use the Weather Research and Forecasting Model with inert tracers. Overall, the model represents well the measured winds, and the inert tracers are in good agreement with observations of comparable trace gas concentrations. The model tracers support the analysis of surface wind and ozone measurements and allow for the analysis of transport patterns and interactions of emissions. A main focus of this study is on characterizing pollution transport from the NFRMA to the mountains by mountain-valley flows and the potential for recirculating pollution back into the NFRMA. One such event on 12 August 2014 was well captured by the aircraft and is studied in more detail. The model represents the flow conditions and demonstrates that during upslope events, frequently, there is a separation of air masses that are heavily influenced by oil and gas emissions to the north and dominated by urban emissions to the south. This case study provides evidence that NFRMA pollution not only can impact the nearby foothills and mountain areas to the east of the Continental Divide but that pollution can spillover into the valleys to the west of the Continental Divide
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