7,196 research outputs found

    Ultra Short Period Planets in K2: SuPerPiG Results for Campaigns 0-5

    Full text link
    We have analyzed data from Campaigns 0-5 of the K2 mission and report 19 ultra-short-period candidate planets with orbital periods of less than 1 day (nine of which have not been previously reported). Planet candidates range in size from 0.7-16 Earth radii and in orbital period from 4.2 to 23.5 hours. One candidate (EPIC 203533312, Kp=12.5) is among the shortest-period planet candidates discovered to date (P=4.2 hours), and, if confirmed as a planet, must have a density of at least rho=8.9 g/cm^3 in order to not be tidally disrupted. Five candidates have nominal radius values in the sub-Jovian desert (R_P=3-11 R_E and P<=1.5 days) where theoretical models do not favor their long-term stability; the only confirmed planet in this range is in fact thought to be disintegrating (EPIC 201637175). In addition to the planet candidates, we report on four objects which may not be planetary, including one with intermittent transits (EPIC 211152484) and three initially promising candidates that are likely false positives based on characteristics of their light curves and on radial velocity follow-up. A list of 91 suspected eclipsing binaries identified at various stages in our vetting process is also provided. Based on an assessment of our survey's completeness, we estimate an occurrence rate for ultra-short period planets among K2 target stars that is about half that estimated from the Kepler sample, raising questions as to whether K2 systems are intrinsically different from Kepler systems, possibly as a result of their different galactic location.Comment: 13 pages, 8 figures, accepted to AJ on 2016 May 2

    Seasonal Occurrence of the White Shark, Carcharodon carcharias, in Waters off the Florida West Coast, with Notes on its Life History

    Get PDF
    The white shark, Carcharodon carcharias, is considered rare in the Gulf of Mexico; however, recent longline captures coupled with historical landings information suggest that the species occurs seasonally (winter-spring) within this region. We examined a total of seven adult and juvenile white sharks (185-472 em total length) captured in waters off the west coast of Florida. Commercial longline fisheries were monitored for white sharks during all months (1981-94), but this species was captured only from January to April. All white sharks were captured in continental shelf waters from 37 to 222 km off the west coast of Florida when sea surface temperatures ranged from 18.7° to 21.6°C. Depths at capture locations ranged from 20 to 164 m. Fishing gear typically used in Gulf of Mexico offshore fisheries may not be effective at capturing this species, and the apparent rarity of white sharks in this area may be, in part, a function of gear bias

    Poincare duality for K-theory of equivariant complex projective spaces

    Get PDF
    We make explicit Poincare duality for the equivariant K-theory of equivariant complex projective spaces. The case of the trivial group provides a new approach to the K-theory orientation

    Changes in the Spatial Allocation of Cropland in the Ft. Cobb Watershed as a Result of Environmental Restrictions

    Get PDF
    Pollution runoff estimates from SWAT are used in a mathematical programming model to optimally model site-specific crop and conservation practices for pollution abatement in the Ft. Cobb watershed in Southwestern Oklahoma. Results indicate the tradeoffs between producer income, sediment and nutrient runoff and the spatial allocation of crops in the watershed.Environmental Economics and Policy,

    Computer Information Systems Development: Analysis and Design

    Get PDF

    Cash, Crops, Chemicals, and Cosmetics: A Mid-Green Eco-Labeling Approach

    Get PDF
    The United States Department of Agriculture (USDA) uses grade standards to uniformly characterize the quality and condition of agricultural commodities. The standards are promulgated by the USDA\u27s Agricultural Marketing Services (AMS) division in consultation with farming industry groups. Emphasizing produce attributes such as surface defects, shape, cleanliness, color, maturity, and decay, grade standards improve the marketability of agricultural commodities by establishing a common industry language for use in contracts. Use of such a language enables wholesale buyers to know the quality of commodities without first having to inspect them, thus facilitating trade by lowering transaction costs
    • …
    corecore