Weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.

Weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.

The order parameter of the recently-discovered ferric arsenide family of superconductors remains uncertain. Some early experiments on polycrystalline samples suggested line nodes in the order parameter, however later experiments on single crystals have strongly supported fully-gapped superconductivity. An absence of nodes does not rule out unconventional order: {pi} phase shifts between the separate Fermi sheets and time-reversal symmetry-breaking components in the order parameter remain possibilities. One test for unconventional order is scanning magnetic microscopy on well-coupled polycrystalline samples: d- or p-wave order would result in orbital frustration, leading to spontaneous currents and magnetization in the superconducting state. We have performed scanning SQUID microscopy on SmFeAsO{sub 0.85} and NdFeAsO{sub 0.94}F{sub 0.06}, and in neither material do we find spontaneous orbital currents, ruling out p- or d-wave order.

Identifying the symmetry of the superconducting order parameter in the recently-discovered ferrooxypnictide family of superconductors, RFeAsO{sub 1-x}F{sub y}, where R is a rare earth, is a high priority. Many of the proposed order parameters have internal {pi} phase shifts, like the d-wave order found in the cuprates, which would result in direction-dependent phase shifts in tunneling. In dense polycrystalline samples, these phase shifts in turn would result in spontaneous orbital currents and magnetization in the superconducting state. We perform scanning SQUID microscopy on a dense polycrystalline sample of NdFeAsO{sub 0.94}F{sub 0.06} with T{sub c} = 48K and find no such spontaneous currents, ruling out many of the proposed order parameters.

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.

Daily newspaper from Sweetwater, Texas that includes local, state, and national news along with advertising.

We quantify natural methane hydrate reservoirs by generating synthetic seismic traces and comparing them to real seismic data: if the synthetic matches the observed data, then the reservoir properties and conditions used in synthetic modeling might be the same as the actual, in-situ reservoir conditions. This approach is model-based: it uses rock physics equations that link the porosity and mineralogy of the host sediment, pressure, and hydrate saturation, and the resulting elastic-wave velocity and density. One result of such seismic forward modeling is a catalogue of seismic reflections of methane hydrate which can serve as a field guide to hydrate identification from real seismic data. We verify this approach using field data from known hydrate deposits.

Daily newspaper from Sweetwater, Texas that includes local, state, and national news along with advertising.

Weekly newspaper from Archer City, Texas that includes local, state, and national news along with advertising.

Weekly newspaper from Nocona, Texas that includes local, state, and national news along with advertising.

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.

Weekly newspaper from Albany, Texas that includes local, county, and state news along with extensive advertising.

Daily newspaper from Sweetwater, Texas that includes local, state, and national news along with advertising.

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.

Biweekly newspaper from Harper, Texas that includes community news along with advertising.

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.

Semiweekly newspaper from Carthage, Texas that includes local, state, and national news along with advertising.

Weekly newspaper from Wylie, Texas that includes local, state and national news along with advertising.

Weekly newspaper from Albany, Texas that includes local, county, and state news along with extensive advertising.

Semiweekly newspaper from Carthage, Texas that includes local, state, and national news along with advertising.

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.