7,809 research outputs found

    Optical BVRI Photometry of Common Proper Motion F/G/K+M Wide Separation Binaries

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    We present optical (BVRI) photometric measurements of a sample of 76 common proper motion wide separation main sequence binary pairs. The pairs are composed of a F-, G-, or K-type primary star and an M-type secondary. The sample is selected from the revised NLTT catalog and the LSPM catalog. The photometry is generally precise to 0.03 mag in all bands. We separate our sample into two groups, dwarf candidates and subdwarf candidates, using the reduced proper motion (RPM) diagram constructed with our improved photometry. The M subdwarf candidates in general have larger VRV-R colors than the M dwarf candidates at a given VIV-I color. This is consistent with an average metallicity difference between the two groups, as predicted by the PHOENIX/BT-Settl models. The improved photometry will be used as input into a technique to determine the metallicities of the M-type stars.Comment: 26 pages, 8 figures, accepted for publication in A

    Comparative Financial Characteristics of U.S. Farms by Type, 2005

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    This study presents and analyzes the mean financial characteristics of different types of crop and livestock farms in the U.S. in 2005. The eighteen farm types are: poultry, beef cattle, hogs, dairy, general livestock, general cash grain, wheat, corn, soybean, grain sorghum, rice, tobacco, cotton, peanut, general crop, fruits and tree nuts, vegetables, and nursery and greenhouse. Significant, two-way statistical differences in mean farm income statement and farm balance sheet variables are highlighted. Results provide a general indication of the comparative profitability, liquidity, solvency, and financial efficiency of different types of U. S. crop and livestock farms.Farm type, ARMS data, financial characteristics, financial ratios, 2005, Agricultural Finance, Production Economics, Q12, Q14, D21,

    Lick Spectral Indices for Super Metal-rich Stars

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    The Lick Fe5015, Fe5270, Fe5335, Mgb and Mg2 indices are presented for 139 candidate SMR stars of different luminosity class studied in Malagnini et al. (2000). Evidence is found for a standard (i.e. [Mg/Fe]~0) Mg vs. Fe relative abundance. Both the Worthey et al. (1994) and Buzzoni et al. (1992, 1994) fitting functions are found to suitably match the data at super-solar metallicity regimes. See http://www.merate.mi.astro.it/~eps/home.html for further details.Comment: 16 pages with 11 figures (Aastex format). To appear in the Nov. '01 issue of the PAS

    DISTRIBUTIONAL IMPACTS OF CAPPING ELIGIBILITY FOR COMMODITY PROGRAM PAYMENTS

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    Adjusted Gross Income, Commodity Payments, Eligibility, Means Test, Resource /Energy Economics and Policy, Q12, Q18,

    Star Formation History and Extinction in the central kpc of M82-like Starbursts

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    We report on the star formation histories and extinction in the central kpc region of a sample of starburst galaxies that have similar far infrared (FIR), 10 micron and K-band luminosities as those of the archetype starburst M82. Our study is based on new optical spectra and previously published K-band photometric data, both sampling the same area around the nucleus. Model starburst spectra were synthesized as a combination of stellar populations of distinct ages formed over the Hubble time, and were fitted to the observed optical spectra and K-band flux. The model is able to reproduce simultaneously the equivalent widths of emission and absorption lines, the continuum fluxes between 3500-7000 Ang, the K-band and the FIR flux. We require a minimum of 3 populations -- (1) a young population of age < 8 Myr, with its corresponding nebular emission, (2) an intermediate-age population (age < 500 Myr), and (3) an old population that forms part of the underlying disk or/and bulge population. The contribution of the old population to the K-band luminosity depends on the birthrate parameter and remains above 60% in the majority of the sample galaxies. Even in the blue band, the intermediate age and old populations contribute more than 40% of the total flux in all the cases. A relatively high contribution from the old stars to the K-band nuclear flux is also apparent from the strength of the 4000 Ang break and the CaII K line. The extinction of the old population is found to be around half of that of the young population. The contribution to the continuum from the relatively old stars has the effect of diluting the emission equivalent widths below the values expected for young bursts. The mean dilution factors are found to be 5 and 3 for the Halpha and Hbeta lines respectively.Comment: 20 pages, uses emulateapj.cls. Scheduled to appear in ApJ Jan 1, 200

    Frost risks in the Mantaro river basin

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    As part of the study on the Mantaro river basin&apos;s (central Andes of Perú) current vulnerability to climate change, the temporal and spatial characteristics of frosts were analysed. These characteristics included intensity, frequency, duration, frost-free periods, area distribution and historical trends. Maps of frost risk were determined for the entire river basin, by means of mathematical algorithms and GIS (Geographic Information Systems) tools, using minimum temperature &amp;ndash; 1960 to 2002 period, geomorphology, slope, land-use, types of soils, vegetation and life zones, emphasizing the rainy season (September to April), when the impacts of frost on agriculture are most severe. We recognized four categories of frost risks: low, moderate, high and critical. The critical risks (with a very high probability of occurrence) were related to high altitudes on the basin (altitudes higher than 3800 m a.s.l.), while the low (or null) probability of occurring risks were found in the lower zones (less than 2500 m a.s.l.). Because of the very intense agricultural activity and the high sensitivity of the main crops (Maize, potato, artichoke) in the Mantaro valley (altitudes between 3100 and 3300 m a.s.l.), moderate to high frost risks can be expected, with a low to moderate probability of occurrence. Another significant result was a positive trend of 8 days per decade in the number of frost days during the rainy season

    The role of the synchrotron component in the mid infrared spectrum of M 87

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    We study in detail the mid-infrared Spitzer-IRS spectrum of M 87 in the range 5 to 20 micron. Thanks to the high sensitivity of our Spitzer-IRS spectra we can disentangle the stellar and nuclear components of this active galaxy. To this end we have properly subtracted from the M 87 spectrum, the contribution of the underlying stellar continuum, derived from passive Virgo galaxies in our sample. The residual is a clear power-law, without any additional thermal component, with a zero point consistent with that obtained by high spatial resolution, ground based observations. The residual is independent of the adopted passive template. This indicates that the 10 micron silicate emission shown in spectra of M 87 can be entirely accounted for by the underlying old stellar population, leaving little room for a possible torus contribution. The MIR power-law has a slope alpha ~ 0.77-0.82 (Sννα_\nu\propto\nu^{-\alpha}), consistent with optically thin synchrotron emission.Comment: 5 pages, 4 figures, accepted for publication in ApJ main journa

    Farm Service Agency Direct Farm Loan Program Effectiveness Study

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    The three primary objectives of the Effectiveness Study are to: (1) identify groups being served by FSA direct farm loan programs, (2) examine the length of time borrowers remain in the programs and the proportion of borrowers who exit or 'graduate' from the programs, and (3) measure and identify ways of reducing loan subsidy rates. The study found that direct Farm Loan Programs (FLPs) appear to be serving their intended clientele. Recent FLP borrowers are more financially stressed than non-borrowers and would be generally considered as family farms. About 78 to 92 percent would qualify as small family farms using USDA's Small Farms Commission definition. FLP credit market penetration is relatively high among farms likely to be eligible for these credit programs, despite the fact that these programs represent a relatively small proportion of total outstanding agricultural debt. Increasing market penetration or the share of farms served by the program would require greater obligation funding and hence greater budgetary costs. Conversely, implementing more rigorous loan eligibility criteria would likely lower the number of operators receiving loans and hence loan loss occurrences and subsidy rates would likely fall. The majority of FSA Direct borrowers from FY 1994-1996 used FLPs as a transitional tool. At time of origination, FSA Direct borrowers had fewer years of farming experience than the farming population at large. More than half of these borrowers no longer had active FLP loans by the end of November 2004. So for the majority of borrowers, FLPs are not a lifetime credit source. FLPs are helping farmers move to commercial credit or aiding farmers who subsequently leave farming completely, as is common among U.S. farmers. Not surprisingly, farmers in stronger financial condition originating FSA Direct loans are more likely to exit and have fewer outstanding loans with FSA. FSA experiences higher loan loss rates than conventional agricultural lenders. This is to be expected because commercial lenders can be more selective in choosing borrowers and price loans to match risk profiles which FSA does not do. In essence, FSA's mission is to provide credit to riskier 'creditworthy' borrowers. The agency is accomplishing this goal. The natural consequence is that FSA loan loss rates are higher than for conventional lenders. Whether the current borrowers are too risky or should even riskier borrowers be included are policy questions. The analysis indicates that attempts to cut losses systematically would imply denying credit to some current borrowers.Agricultural Finance,
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