Preliminary results of the heavy-light meson spectrum using chirally improved light quarks

Using a ``wall'' of quark point sources, we invert the chirally improved Dirac operator to create an ``incoherent'' collection of quark propagators which originate from all spatial points of the source time slice. The lowest-order NRQCD approximation is used to create heavy-quark propagators from the same wall source. However, since the numerical cost involved in computing such heavy-quark propagators is low, we are able to use a number of source gauge paths to establish coherence between the heavy and light quarks at several spatial separations. The resulting collection of heavy-light meson correlators is analyzed to extract the corresponding mass spectrum.Comment: 3 pages, 1 figure, Lattice2004(spectrum), minor corrections adde

Energies of B_s meson excited states - a lattice study

This is a follow-up to our earlier work on the energies and radial distributions of heavy-light mesons. The heavy quark is taken to be static (infinitely heavy) and the light quark has a mass about that of the strange quark. We now concentrate on the energies of the excited states with higher angular momentum and with a radial node. A new improvement is the use of hypercubic blocking in the time direction. The calculation is carried out with dynamical fermions on a 16 cubed times 32 lattice with a lattice spacing approximately 0.1 fm generated using a non-perturbatively improved clover action. In nature the closest equivalent of this heavy-light system is the B_s meson, which allows us to compare our lattice calculations to experimental results (where available) or to give a prediction where the excited states, particularly P-wave states, should lie. We pay special attention to the spin-orbit splitting, to see which one of the states (for a given angular momentum L) has the lower energy. An attempt is made to understand these results in terms of the Dirac equation.Comment: 35 pages. v3: Data from two new lattices added. New results in several chapter

Decays of mesons with charm quarks on the lattice

We investigate mesons containing charm quarks on fine lattices with a^{-1} \sim 5 GeV. The quenched approximation is employed using the Wilson gauge action at \beta = 6.6 and nonperturbatively O(a) improved Wilson quarks. We present results for decay constants using various interpolating fields and give preliminary results for form factors of semileptonic decays of D_s mesons to light pseudoscalar mesons.Comment: 7 pages, 3 figures, talk presented at the XXV International Symposium on Lattice Field Theory, 30 July - 4 August 2007, Regensburg, German

The Missouri plan of sheep improvement

"March, 1940""Missouri ranks as the leading state in the corn belt in the production of early spring lambs. A relatively short winter with sufficiently low temperatures to hold sheep parasites in check, and an early spring, make conditions nearly ideal for the production of February lambs. Pasture from bluegrass and the small grains (wheat, rye, barley and oats mixed with rape) supplies early spring grazing for ewes. A liberal milk flow as a result of good pasture enables February and March lambs to reach the late May and early June market. These natural conditions and the proximinity of markets give Missouri sheep raisers advantages not common in other sections of the corn belt."--First paragraph.T.A. Ewing, and J.W. Burc

Care and hitches for work horses

May, 1939."Revision of Circular 287.