\u3ci\u3eUrophora Affinis\u3c/i\u3e and \u3ci\u3eU. Quadrifasciata\u3c/i\u3e (Diptera: Tephritidae) Released and Monitored by USDA, APHIS, PPQ as Biological Control Agents of Spotted and Diffuse Knapweed

USDA, APHIS, PPQ has distributed the seedhead gall flies Urophora affinis and U. quadrifasciata (Diptera: Tephritidae) as classical biological agents of the introduced weeds spotted and diffuse knapweed (Centaurea maculosa and C. diffusa, respectively) (Asteraceae) in the United States. From 1987 to 1996, Urophora spp. have been released in 97 counties in 14 midwestern and western states. Established populations of U. affinis and U. quadrifasciata are confirmed in 85 and 95 counties, respectively, among all 14 states. These include the first reports of successful establishment of Urophora spp. in Arizona (two counties), Colorado (eight counties), Michigan (one county), Minnesota (six counties), Nebraska (four counties), Nevada (two counties), North Dakota (one county), South Dakota (four coun­ties), Utah (three counties), and Wisconsin (two counties). The first confirmed establishment of U. quadrifasciata in Indiana and Michigan is also reported

Towards a quantum field theory of primitive string fields

We denote generating functions of massless even higher spin fields "primitive string fields" (PSF's). In an introduction we present the necessary definitions and derive propagators and currents of these PDF's on flat space. Their off-shell cubic interaction can be derived after all off-shell cubic interactions of triplets of higher spin fields have become known [2],[3]. Then we discuss four-point functions of any quartet of PSF's. In subsequent sections we exploit the fact that higher spin field theories in $AdS_{d+1}$ are determined by AdS/CFT correspondence from universality classes of critical systems in $d$ dimensional flat spaces. The O(N) invariant sectors of the O(N) vector models for $1\leq N \leq \infty$ play for us the role of "standard models", for varying $N$, they contain e.g. the Ising model for N=1 and the spherical model for $N=\infty$. A formula for the masses squared that break gauge symmetry for these O(N) classes is presented for d = 3. For the PSF on $AdS$ space it is shown that it can be derived by lifting the PSF on flat space by a simple kernel which contains the sum over all spins. Finally we use an algorithm to derive all symmetric tensor higher spin fields. They arise from monomials of scalar fields by derivation and selection of conformal (quasiprimary) fields. Typically one monomial produces a multiplet of spin $s$ conformal higher spin fields for all $s \geq 4$, they are distinguished by their anomalous dimensions (in $CFT_3$) or by their mass (in $AdS_4$). We sum over these multiplets and the spins to obtain "string type fields", one for each such monomial.Comment: 16 pages,Late

Cleaning the USNO-B Catalog through automatic detection of optical artifacts

The USNO-B Catalog contains spurious entries that are caused by diffraction spikes and circular reflection halos around bright stars in the original imaging data. These spurious entries appear in the Catalog as if they were real stars; they are confusing for some scientific tasks. The spurious entries can be identified by simple computer vision techniques because they produce repeatable patterns on the sky. Some techniques employed here are variants of the Hough transform, one of which is sensitive to (two-dimensional) overdensities of faint stars in thin right-angle cross patterns centered on bright (<13 \mag) stars, and one of which is sensitive to thin annular overdensities centered on very bright (<7 \mag) stars. After enforcing conservative statistical requirements on spurious-entry identifications, we find that of the 1,042,618,261 entries in the USNO-B Catalog, 24,148,382 of them (2.3 \percent) are identified as spurious by diffraction-spike criteria and 196,133 (0.02 \percent) are identified as spurious by reflection-halo criteria. The spurious entries are often detected in more than 2 bands and are not overwhelmingly outliers in any photometric properties; they therefore cannot be rejected easily on other grounds, i.e., without the use of computer vision techniques. We demonstrate our method, and return to the community in electronic form a table of spurious entries in the Catalog.Comment: published in A

The Measure of the Orthogonal Polynomials Related to Fibonacci Chains: The Periodic Case

The spectral measure for the two families of orthogonal polynomial systems related to periodic chains with N-particle elementary unit and nearest neighbour harmonic interaction is computed using two different methods. The interest is in the orthogonal polynomials related to Fibonacci chains in the periodic approximation. The relation of the measure to appropriately defined Green's functions is established.Comment: 19 pages, TeX, 3 scanned figures, uuencoded file, original figures on request, some misprints corrected, tbp: J. Phys.

Balloon tank skin strain measurements at liquid-hydrogen temperature on centaur flight vehicle

Balloon tank skin strain measurements at liquid hydrogen temperature on Centaur flight vehicl

The Chandra Detection of Galactic Center X-ray Features G359.89-0.08 and G359.54+0.18

We report on the detection of two elongated X-ray features G359.89-0.08 and G359.54+0.18 in the Galactic center (GC) region using the Chandra X-ray Observatory. G359.89-0.08 is an elongated X-ray feature located $\sim$2\arcmin in projection south of the center of the Galaxy, SgrA$^*$. This X-ray feature source is partially coincident with a slightly curved (``wisp''-like) non-thermal radio source. The X-ray spectrum of G359.89-0.08 can be best characterized as non-thermal, with a photon index of 2. The morphological and spectral characteristics of the X-ray and radio emission associated with G359.89-0.08 are best interpreted as the synchrotron emission from a ram-pressure confined pulsar wind nebula. G359.54+0.18 is one of the most prominent radio non-thermal filaments (NTFs) in the GC region, located $\sim$30\arcmin in projection from SgrA$^*$. A narrow ($\sim$10\arcsec) filament of X-ray emission appears to arise from one of the two strands that comprise the radio NTF. Although the photon statistics are poor for this source, the X-ray emission is also likely to be non-thermal in nature. Several models for the production of X-ray emission in G359.54+0.18 are discussed.Comment: 19 pages with 6 figures included, accepted by A

Pairing and superconductivity driven by strong quasiparticle renormalization in two-dimensional organic charge transfer salts

We introduce and analyze a variational wave function for quasi two-dimensional kappa-ET organic salts containing strong local and nonlocal correlation effects. We find an unconventional superconducting ground state for intermediate charge carrier interaction, sandwiched between a conventional metal at weak coupling and a spin liquid at larger coupling. Most remarkably, the excitation spectrum is dramatically renormalized and is found to be the driving force for the formation of the unusual superconducting state.Comment: 4 pages, 4 figure