Looking for Stars and Finding the Moon: Effects of Lunar Gamma-ray Emission on Fermi LAT Light Curves

We are conducting a search for new gamma-ray binaries by making high signal-to-noise light curves of all cataloged Fermi LAT sources and searching for periodic variability using appropriately weighted power spectra. The light curves are created using a variant of aperture photometry where photons are weighted by the probability that they came from the source of interest. From this analysis we find that the light curves of a number of sources near the ecliptic plane are contaminated by gamma-ray emission from the Moon. This shows itself as modulation on the Moon's sidereal period in the power spectra. We demonstrate that this contamination can be removed by excluding times when the Moon was too close to a source. We advocate that this data screening should generally be used when analyzing LAT data from a source located close to the path of the Moon.Comment: 2012 Fermi Symposium proceedings - eConf C12102

Pion-Nucleus Scattering at Medium Energies with Densities from Chiral Effective Field Theories

Recently developed chiral effective field theory models provide excellent descriptions of the bulk characteristics of finite nuclei, but have not been tested with other observables. In this work, densities from both relativistic point-coupling models and mean-field meson models are used in the analysis of meson-nucleus scattering at medium energies. Elastic scattering observables for 790 MeV/$c$ $\pi^{\pm}$ on $^{208}$Pb are calculated in a relativistic impulse approximation, using the Kemmer-Duffin-Petiau formalism to calculate the $\pi^{\pm}$ nucleus optical potential.Comment: 9 page

Postal card from C. S. Tingey, as well as a letter from W. J. Kerr

Postal card and letter concerning a state warrant

Comment on "Nonlinear eigenvalue problems"

The asymptotic behaviour of solutions to $y'(x)=\cos[\pi x y(x)]$ was investigated by Bender, Fring and Komijani (2014). They found, for example, a relation between the initial value $y(0)=a$ and the number of maxima that the solution exhibited. We present an alternative derivation of the asymptotic results that looks at the solutions in the regions $xy$, and confirms the behaviour found previously for larger values of $a$. This method uses the small amplitude and high frequency of the oscillatory behaviour in the region $x<y$