249 Matching Results

Search Results

Advanced search parameters have been applied.
in subjects: "Solar Radiation"  
Results: 1 - 24 next
open access

Experimental and theoretical investigations of marine stratocumulus cloud sensitivity to climate parameters using ship-trail clouds

Description: The formation and radiative properties of clouds are poorly parameterized in numerical climate models, especially marine boundary layer clouds. Twomey (1991), after describing the importance of cloud microphysics to the climate problem, states Clearly, many more field measurements and laboratory experiments are called for, rather than endless repetitions of computer simulations that are closely related to each other and parameterize in very similar ways.'' The effort described here is a field e… more
Date: January 1, 1991
Creator: Porch, W.; Buchwald, M.; Glatzmaier, T.; Kao, C.-Y.; Unruh, W. (Los Alamos National Lab., NM (United States)); Hudson, J. et al.
Partner: UNT Libraries Government Documents Department
open access

Giotto observations of the bow shock at Comet Halley

Description: Preliminary results from the JPA instrument on Giotto indicate that Comet Halley, even on the flanks, has a bow shock which moves backwards and forwards over the spacecraft. To understand the structure properly will require more detailed investigation of the relationships between three particle populations, cometary ions, solar wind ions and electrons.
Date: January 1, 1986
Creator: Formisano, V.; Amata, E.; Wilken, B.; Jockers, K.; Johnstone, A.; Coates, A. et al.
Partner: UNT Libraries Government Documents Department
open access

The Soviet American Gallium Experiment (SAGE)

Description: A radiochemical experiment using the reaction v/sub e/ = /sup 71/Ga + e/sup e/ to determine the integral flux of low-energy neutrinos from the sun is currently under preparation at the Baksan Neutrino Observatory in the USSR. Measurements are scheduled to commence by late 1988 using /approximately/30 tonnes of metallic gallium. With this amount of gallium it should be possible to obtain a fractional statistical accuracy of 12 to 15% after one year (assuming the standard solar model neutrino flu… more
Date: January 1, 1988
Creator: Abazov, A. I.; Abdurashitov, D. N.; Anosov, O. P.; Avdeyev, A. V.; Belousko, Yu. I.; Bychuk, O. V. et al.
Partner: UNT Libraries Government Documents Department
open access

The GALLEX Project

Description: The GALLEX collaboration aims at the detection of solar neutrinos in a radiochemical experiment employing 30 tons of Gallium in form of concentrated aqueous Gallium-chloride solution. The detector is primarily sensitive to the otherwise inaccessible pp-neutrinos. Details of the experiment have been repeatedly described before. Here we report the present status of implementation in the Laboratori Nazionali del Gran Sasso (Italy). So far, 12.2 tons of Gallium are at hand. The present status of de… more
Date: January 1, 1989
Creator: Kirsten, T. (Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany, F.R.))
Partner: UNT Libraries Government Documents Department
open access

UV action spectra for mammalian systems: their implications for the predicted effects of ozone depletion on skin cancer incidence

Description: The predicted environmental effect of UV-B depend on the action spectrum for the response studied. Since such spectra change rapidly - usually decreasing with increasing wavelength - and since the biological effects depend on the product of the action spectrum and the sun's spectrum at the surface of the earth which decreases with decreasing wavelength, a slight change in action spectrum will markedly influence the predicted effects of ozone depletion on biological systems. Thus, the key, but b… more
Date: January 1, 1982
Creator: Setlow, R.B.
Partner: UNT Libraries Government Documents Department
open access

Counterstreaming solar wind halo electron events on open field lines

Description: Counterstreaming solar wind halo electron events have been identified as a common 1 AU signature of coronal mass ejection events, and have generally been interpreted as indicative of closed magnetic field topologies, i.e., magnetic loops or flux ropes rooted at both ends in the Sun, or detached plasmoids. In this paper we examine the possibility that these events may instead occur preferentially on open field lines, and that counterstreaming results from reflection or injection behind interplan… more
Date: January 1, 1991
Creator: Gosling, J.T.; McComas, D.J. & Phillips, J.L.
Partner: UNT Libraries Government Documents Department
open access

Gamow-Teller strength functions and neutrino problems

Description: A quantitative understanding of spin strengths in nuclei is of vital importance in studies of nuclear double beta decay and in solar neutrino spectroscopy. The current status of these problems is outlined.
Date: January 1, 1982
Creator: Haxton, W. C.
Partner: UNT Libraries Government Documents Department
open access

Quantitative analysis of bidirectional electron fluxes within coronal mass ejections at 1 AU

Description: The solar wind electron heat flux is carried primarily by suprathermal halo'' electrons beamed antisunward along the interplanetary magnetic field (IMF), indicating magnetic connection to the Sun only in one direction. However, electron observations at 1 AU show that counterstreaming halo beams, suggesting closed magnetic structures, prevail within coronal mass ejections (CMEs). These structures might be magnetic tongues'', tied to the Sun at both ends, magnetically detached plasmoids, or compl… more
Date: January 1, 1991
Creator: Phillips, J.L.; Gosling, J.T.; McComas, D.J.; Bame, S.J. & Feldman, W.C.
Partner: UNT Libraries Government Documents Department
open access

Particle Cosmology Comes of Age

Description: The application of modern ideas in particle physics to astrophysical and cosmological settings is a continuation of a fruitful tradition in astrophysics which began with the application of atomic physics, and then nuclear physics. In the past decade particle cosmology and particle astrophysics have been recognized as 'legitimate activities' by both particle physicists and astrophysicists and astronomers. During this time there has been a high level of theoretical activity producing much specula… more
Date: December 1, 1987
Creator: Turner, M. S.
Partner: UNT Libraries Government Documents Department
open access

Resonant enhancement of flavor-changing neutrino interactions

Description: The resonant amplification of neutrino oscillations in the presence of flavor-changing neutrino interactions with matter is analyzed. It is shown that a significant {mu}-flavor conversion can take place even in the absence of neutrino mixing in vacuum. To account for the solar neutrino deficit, the strength of the new interactions should be {approximately} 10{sup {minus}2}G{sub F} and the resulting neutrino suppression and spectrum is similar to that in the ordinary MSW effect. I discuss some e… more
Date: October 1, 1991
Creator: Roulet, E.
Partner: UNT Libraries Government Documents Department
open access

Solar neutrinos: theory vs experiment

Description: I review the standard solar model, the disparities between its predictions and the solar neutrino flux measurements of the Homestake and Kamioka II collaborations, and possible particle physics resolutions of this puzzle. The effects of matter, including density fluctuations and turbulence, on solar neutrino oscillations are reviewed, including possibilities for generating time variations in the solar neutrino flux. Finally, I consider possible outcomes and implications of the SAGE/GALLEX galli… more
Date: January 1, 1991
Creator: Haxton, W. C.
Partner: UNT Libraries Government Documents Department
open access

MSW effect and solar neutrino experiments

Description: We describe the MSW solutions to the /sup 37/Cl solar neutrino experiment, and their implications for the /sup 71/Ga experiment. Measurement of the spectrum of electron-type neutrinos arriving at earth is emphasized. 8 refs., 2 figs., 1 tab.
Date: January 1, 1986
Creator: Rosen, S. P.
Partner: UNT Libraries Government Documents Department
open access

XIX Recontre de Moriond. Summary talk

Description: The theoretical arguments for neutrino mass are reviewed, and the present status of searches for neutrino mass in neutrino oscillations, direct measurements and other experiments are summarized. 46 references.
Date: January 1, 1984
Creator: Rosen, S.P.
Partner: UNT Libraries Government Documents Department
open access

Particle detection using superfluid helium

Description: We have observed 5 MeV {alpha} particles stopped in volumes-up to two liters of liquid helium at 70 mK. A fraction of the kinetic energy of an {alpha} particle is converted to elementary excitations (rotons and phonons), which progagate ballistically in isotopically pure {sup 4}He below 0.1 K. Most of these excitations have sufficient energy to evaporate helium atoms on hitting a free surface. The evaporated helium atoms can be detected calorimetrically when adsorbed on a thin silicon wafer ({a… more
Date: January 1, 1991
Creator: Bandler, S. R.; Lanou, R. E.; Maris, H. J.; More, T.; Porter, F. S.; Seidel, G. M. et al.
Partner: UNT Libraries Government Documents Department
open access

Clouds and Radiation Testbed Data Environment: Site data system and experiment center

Description: The Department of Energy (DOE) has initiated the Atmospheric Radiation Measurement (ARM) program as a research effort to reduce the uncertainties found in general circulation and other models due to the effects of clouds and solar radiation (DOE 1990, Patrinos, et al. 1990). This program will provide an experimental testbed for the study of important atmospheric effects, particularly cloud and radiative processes, and testing of parameterizations of the processes for use in atmospheric models. … more
Date: January 1, 1992
Creator: Melton, R.B.; Bobrowski, S.F. (Pacific Northwest Lab., Richland, WA (United States)); Campbell, A.P. (Argonne National Lab., IL (United States)); Corbet, J.M. (National Center for Atmospheric Research, Boulder, CO (United States)); Edwards, D.M. (Sandia National Labs., Livermore, CA (United States)); Kanciruk, P. (Oak Ridge National Lab., TN (United States)) et al.
Partner: UNT Libraries Government Documents Department
open access

Sunlight activation of shale-oil byproducts as measured by genotoxic effects in cultured Chinese hamster cells

Description: Activation of certain classes of promutagens/procarcinogens can be accomplished by exposure to various radiation sources. Retort processes currently in use in the production of shale oil generate significant quantities of process waters which contain a wide spectrum of uv-absorbing, organic material. Photoactivation of these waters with an artificial source of NUV results in genotoxic events in cultured mammalian cells. Since significant amounts (2 to 4%) of solar radiation reaching the earth's… more
Date: January 1, 1981
Creator: Strniste, G.F.; Chen, D.J. & Okinaka, R.T.
Partner: UNT Libraries Government Documents Department
open access

Feasibility of 81Br(Nu e-) 81Kr Solar Neutrino Experiment

Description: Several ingenious solutions have been offered for the solar neutrino problem - a defect in the solar model, the appearance of a new type of neutrino physics, the sun is no longer burning, etc. The range of these proffered solutions stresses the need for a new experiment to study the sun. The modern pulsed laser now makes possible a new solar neutrino test which examines an independent neutrino source in the sun. A recently proposed experiment would use the reaction /sup 81/Br(nu,e/sup -/)/sup 8… more
Date: May 1, 1985
Creator: Hurst, G. S.; Allman, S. L.; Chen, C. H.; Kramer, S. D.; Thomson, J. O. & Cleveland, B.
Partner: UNT Libraries Government Documents Department
open access

Neutrino oscillations: An essay in honor of Felix Boehm

Description: We briefly review the theory of neutrino oscillations and the MSW effect and report on new calculations by Rosen and Gelb for solar neutrino-electron scattering. The aim of these calculations is to try to use the scattering process as a means of choosing between the three types of MSW solutions for the {sup 37}Cl experiment. Both the efficiency and the resolution of the Kamiokande II detector are taken into account and the ratio R of the MSW prediction to the standard solar model prediction is … more
Date: January 1, 1989
Creator: Rosen, S.P.
Partner: UNT Libraries Government Documents Department
open access

Feasibility of a /sup 81/(. nu. ,e/sup -/)/sup 81/Kr solar neutrino experiment

Description: Discrepancies between standard model predictions and observed values of the solar neutrinos flux are described. A proposed experiment is discussed including facilities and compounds required, signal level, and background effects. 16 refs., 2 figs., 1 tab. (DWL)
Date: January 1, 1986
Creator: Hurst, G.S.
Partner: UNT Libraries Government Documents Department
open access

Review of the physics of the neutrino

Description: The status of knowledge with respect to neutrinos is reviewed. Questions covered briefly include whether or not a neutrino is its own antiparticle and neutrino mass. Experimental studies are also considered, including neutrino oscillations, double beta decay, and direct neutrino mass measurements. (LEW)
Date: January 1, 1986
Creator: Robertson, R.G.H.
Partner: UNT Libraries Government Documents Department
open access

Lunar radionuclide records of average solar-cosmic-ray fluxes over the last ten million years

Description: Because changes in solar activity can modify the fluxes of cosmic-ray particles in the solar system, the nature of the galactic and solar cosmic rays and their interactions with matter are described and used to study the ancient sun. The use of cosmogenic nuclides in meteorites and lunar samples as detectors of past cosmic-ray variations are discussed. Meteorite records of the history of the galactic cosmic rays are reviewed. The fluxes of solar protons over various time periods as determined f… more
Date: March 21, 1980
Creator: Reedy, R. C.
Partner: UNT Libraries Government Documents Department
open access

Underground science initiatives at Los Alamos

Description: Recently, the Los Alamos National Laboratory has proposed two major new initiatives in underground science. Following the dissolution of the original gallium solar neutrino collaboration, Los Alamos has formed a new North American collaboration. We briefly review the rationale for solar neutrino research, outline the proposal and new Monte Carlo simulations, and describe the candidate locations for the experiment. Because there is no dedicated deep underground site in North America suitable for… more
Date: January 1, 1985
Creator: Simmons, L.M. Jr.
Partner: UNT Libraries Government Documents Department
open access

Large-basis shell-model technology in nucleosynthesis and cosmology

Description: We discuss various applications of the Lanczos method to describe properties of many-body microscopic systems in nucleosynthesis and cosmology. These calculations include: solar neutrino detectors; beta-decay of excited nuclear states; electron-capture rates during a core-bounce supernova; exotic quarked nuclei as a catalyst for hydrogen burning; and the quark-hadron phase transition during the early universe. 27 refs., 3 figs.
Date: May 1, 1985
Creator: Mathews, G. J.; Bloom, S. D.; Takahashi, K.; Fuller, G. M. & Hausman Jr., R. F.
Partner: UNT Libraries Government Documents Department
open access

Application of the adjoint method in atmospheric radiative transfer calculations

Description: The transfer of solar radiation through a standard mid-latitude summer atmosphere including different amounts of aerosols (from clear to hazy) has been computed. The discrete-ordinates (S/sub N/) method, which has been developed to a high degree of computational efficiency and accuracy primarily for nuclear radiation shielding applications, is employed in a forward as well as adjoint mode. In the adjoint mode the result of a transfer calculation is an importance function (adjoint intensity) whi… more
Date: January 1, 1979
Creator: Gerstl, S.A.W.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen