408,250 research outputs found
Plasmaspheric H+, He+, He++, O+, and O++ Densities and Temperatures
Thermal plasmaspheric densities and temperatures for five ion species have recently become available, even though these quantities were derived some time ago from the Retarding Ion Mass Spectrometer onboard the Dynamics Explorer 1 satellite over the years 1981-1984. The quantitative properties will be presented. Densities are found to have one behavior with lessor statistical variation below about L=2 and another with much greater variability above that Lshell. Temperatures also have a behavior difference between low and higher L-values. The density ratio He++/H+ is the best behaved with values of about 0.2% that slightly increase with increasing L. Unlike the He+/H+ density ratio that on average decreases with increasing Lvalue, the O+/H+ and O++/H+ density ratios have decreasing values below about L=2 and increasing average ratios at higher L-values. Hydrogen ion temperatures range from about 0.2 eV to several 10s of eV for a few measurements, although the bulk of the observations are of temperatures below 3 eV, again increasing with L-value. The temperature ratios of He+/H+ are tightly ordered around 1.0 except for the middle plasmasphere between L=3.5 and 4.5 where He+ temperatures can be significantly higher. The temperatures of He++, O+, and O++ are consistently higher than H+
High Resolution Spectroscopy of SN1987A's Rings: He I 10830 and H-alpha from the Hotspots
We present the first high-dispersion spectroscopy of He I 10830 from the
hotspots in the ring around SN1987A, obtained at Gemini South, spatially
resolving the near and far sides of the ring. We compare these line profiles to
similar echelle spectra of H and [N II] 6583 obtained at the Magellan
Observatory. We find that the He I profiles are much broader than H-alpha or [N
II], but the He I profiles also have different shapes -- they have enhanced
emission at high speeds, with extra blueshifted emission on the north side of
the ring, and extra redshifted emission on the south side. To explain this, we
invoke a simple geometric picture where the extra He I emission traces hotter
gas from faster shocks that strike the apex of the hotspots directly, while the
H-alpha preferentially traces cooler lower-ionization gas from slower
transverse shocks that penetrate into the sides of the ring.Comment: 3 pages. To appear in proceedings: "Supernova 1987A: 20 Years After:
Supernovae and Gamma-Ray Bursters" AIP, New York, eds. S. Immler, K.W.
Weiler, and R. McCra
Plasmaspheric H+, He+, O+, He++, and O++ Densities and Temperatures
Thermal plasmaspheric densities and temperatures for five ion species have recently become available, even though these quantities were derived some time ago from the Retarding Ion Mass Spectrometer onboard the Dynamics Explorer 1 satellite over the years 1981-1984. The quantitative properties will be presented. Densities are found to have one behavior with lessor statistical variation below about L=2 and another with much greater variability above that Lshell. Temperatures also have a behavior difference between low and higher L-values. The density ratio He++/H+ is the best behaved with values of about 0.2% that slightly increase with increasing L. Unlike the He+/H+ density ratio that on average decreases with increasing Lvalue, the O+/H+ and O++/H+ density ratios have decreasing values below about L=2 and increasing average ratios at higher L-values. Hydrogen ion temperatures range from about 0.2 eV to several 10s of eV for a few measurements, although the bulk of the observations are of temperatures below 3 eV, again increasing with L-value. The temperature ratios of He+/H+ are tightly ordered around 1.0 except for the middle plasmasphere between L=3.5 and 4.5 where He+ temperatures can be significantly higher. The temperatures of He++, O+, and O++ are consistently higher than H+
Impact Analysis of a Small-Scale Irrigation Project in Manicahan District, Zamboanga City
This article is a product of a nine-month training and application program implemented by the micro component of the Economic and Social Impact Analysis/Women in Development (ESIA/WID) and the Food Systems Program of the East-West Center Resource Systems Institute (RSI). It focuses on the 300-hectare, small-scale irrigation system in Manicahan District and its impact on the employment levels on farms within the irrigated area.infrastructure, irrigation system, rural sector, farm lands, infrastructural development, impact analysis
The Philippines: External Shocks, Adjustment Policies and Impact on Selected Development Concerns, 1973-1985
With the objective of designing and implementing more effective policies and programs in the light of external shocks, this paper assesses the impact of economic crisis and adjustment policies on basic economic and social concerns particularly on vulnerable income groups. The development path implied in this article is a strategy that is expansionary within the limits set by external finance and other policy considerations.vulnerable groups, adjustment policies
Impact Analysis of a Small-Scale Irrigation Project in Manicahan District, Zamboanga City
This article is a product of a nine-month training and application program implemented by the micro component of the Economic and Social Impact Analysis/Women in Development (ESIA/WID) and the Food Systems Program of the East-West Center Resource Systems Institute (RSI). It focuses on the 300-hectare, small-scale irrigation system in Manicahan District and its impact on the employment levels on farms within the irrigated area.infrastructure, irrigation system, rural sector, farm lands, infrastructural development, impact analysis
Invertebrata Pacifica. (1903-7). Edited by C. F. Baker. Hampton, Middlesex, England: E. W. Classey, 1969. [ii], 197 pp. $10.80.
Excerpt: Charles Fuller Baker (1872-1927) was born in Lansing, Michigan, and received his undergraduate degree from Michigan Agricultural College [now Michigan State University) in 1892. While on the faculty of the Colorado Agricultural College he collected extensively in the West, specializing in the Homoptera. After a decade of varied employment, ranging from service as botanist on the H. H. Smith expedition to Colombia (1898-99) to teaching high school in St. Louis, he returned to academic life and obtained his M.S. at Stanford in 1903
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