Infrared regularization for spin-1 fields

We extend the method of infrared regularization to spin-1 fields. As applications, we discuss the chiral extrapolation of the rho meson mass from lattice QCD data and the pion-rho sigma term.Comment: 22 pp, 5 fig

A formalism for the study of K+π ΣK^{+}\pi\,\Sigma photoproduction in the Λ∗(1405)\Lambda^{\ast}(1405) region

We present a formalism for the low-energy analysis of the $\gamma p\rightarrow K^{+}\pi\Sigma$ photoproduction reaction in the $\Lambda^{\ast}(1405)$ resonance region. In particular, the constraints arising from unitarity, gauge invariance and chiral perturbation theory are discussed in some detail

Effect of Exopolymers on the Consumption of Synechococcus by Oxyrrhis marina

Microscopic organisms play an important role in carbon cycling in the ocean. Because of their large role, understanding how their activity is affected by other organisms and by particles in the water is important to understand the oceanic carbon cycle and flow of energy through food webs. This experiment was designed to determine what effect, if any, transparent exopolymer particles (TEP) have on the consumption of Synechococcus by Oxyrrhis marina. O. marina is a heterotrophic marine dinoflagellate that has the potential to be a model organism for heterotrophic dinoflagellates and protists. Synechococcus is a cyanobacterium that is responsible for a quarter of yearly marine net primary production. Because TEP are adhesive, they form aggregates of small particles such as Synechococcus. In this experiment, cultures containing O. marina and Synechococcus with TEP added saw a significant increase in the average number of Synechococcus consumed by O. marina. This is likely because the size of the aggregates of Synechococcus formed by TEP are more appealing to O. marina than individual Synechococcus cells. The results of this experiment suggest that the presence of TEP will increase the amount of carbon flow to upper trophic levels by causing higher consumption at lower levels due to prey aggregation