Single-spin asymmetries in the leptoproduction of transversely polarized Λ\Lambda hyperons

We analyze single-spin asymmetries (SSAs) in the leptoproduction of transversely polarized $\Lambda$ hyperons within the collinear twist-3 formalism. We calculate both the distribution and fragmentation terms in two different gauges (lightcone and Feynman) and show that the results are identical. This is the first time that the fragmentation piece has been analyzed for transversely polarized hadron production within the collinear twist-3 framework. In lightcone gauge we use the same techniques that were employed in computing the analogous piece in $p^\uparrow p\to \pi\,X$, which has become an important part to that reaction. With this in mind, we also verify the gauge invariance of the formulas for the transverse SSA in the leptoproduction of pions.Comment: 12 pages, 1 figure, reference added, version to appear in Phys. Lett.

Large-Scale Dryland Cropping Systems

A large-scale dryland cropping systems research and demonstration project at the Southwest Research-Extension Center near Tribune, Kansas, evaluated two summer crops (corn and grain sorghum) along with winter wheat in crop rotations varying in length from 1 to 4 years. The rotations were continuous grain sorghum, wheat-fallow, wheat-corn-fallow, wheat-sorghum-fallow, wheat-corn-sorghum-fallow, and wheatsorghum- corn-fallow. The objective of the study is to identify cropping systems that enhance and stabilize production in rain-fed locations to optimize economic crop production. Averaged across the past 7 years, wheat yields ranged from 22 to 25 bu/a and were not affected by length of rotation. Corn and grain sorghum yields (7-year average) were about twice as great when following wheat than when following corn or grain sorghum. Grain sorghum yields were almost twice as great as those of corn in similar rotations

Alternative Cropping Systems with Limited Irrigation

A limited irrigation study involving six cropping systems was initiated at the Southwest Research-Extension Center near Tribune, KS, in 2012. The cropping systems were two annual systems (continuous corn [C-C] and continuous grain sorghum [GS-GS]) and four 2-year systems (corn-sorghum [C-GS]), corn-sunflower [C-SF], corn-winter wheat [C-W], and corn-wheat/double sunflower [C-W/SF]). In 2015, corn yields were lower following corn than other crops while wheat and grain sorghum yields were similar for all rotations. This tended to agree with the 3-year average yields except for average sorghum yields being higher following corn than sorghum. Sunflowers were destroyed by rodents and no yields were obtained