Evidence for new unidentified TeV gamma-ray sources from angularly-correlated hot-spots observed by independent TeV gamma-ray sky surveys

We have examined the directional cross-correlation of statistical `hot-spots' between a Northern Sky TeV Gamma Ray Survey by the Milagro Observatory and a similar survey by the Tibet Array. We find the directions of these hot-spots are angularly uncorrelated between the two surveys for large angular separations (Delta theta > 4 degrees), but there appears to be a statistically significant correlation between hot-spot directions for Delta theta < 1.5 degrees. Independent simulations indicate the chance probability for the occurrence of this correlation is approximately 10^-4, implying the existence of one or more previously unobserved TeV gamma-ray sources in these directions. The data sets are consistent with both point-like sources or diffuse sources with extent of 1 - 2 degrees.Comment: 12 pages, 2 figures, 3 tables. Submitted to Astrophysical Journal Letter

Multiple jet study data correlations

Correlations are presented which allow determination of penetration and mixing of multiple cold air jets injected normal to a ducted subsonic heated primary air stream. Correlations were obtained over jet-to-primary stream momentum flux ratios of 6 to 60 for locations from 1 to 30 jet diameters downstream of the injection plane. The range of geometric and operating variables makes the correlations relevant to gas turbine combustors. Correlations were obtained for the mixing efficiency between jets and primary stream using an energy exchange parameter. Also jet centerplane velocity and temperature trajectories were correlated and centerplane dimensionless temperature distributions defined. An assumption of a Gaussian vertical temperature distribution at all stations is shown to result in a reasonable temperature field model. Data are presented which allow comparison of predicted and measured values over the range of conditions specified above

Flat conductor cable survey

Design handbook contains data and illustrations concerned with commercial and Government flat-conductor-cable connecting and terminating hardware. Material was obtained from a NASA-sponsored industry-wide survey of approximately 150 companies and Government agencies

<i>Aloe succotrina</i> (Asphodelaceae)

Aloe succotrina has a very long and complex taxonomic and nomenclatural history with wrong synonymy that is rivalled by few other aloes. This is mostly due to early authors wrongly assuming that this plant is from the Island of Socotra (Reynolds 1950). It has been in cultivation in Europe for over three hundred years, so consequently it is rather surprising that this iconic fynbos species has not featured in this journal until now

Circular Dichroism of RbHe and RbN2_2 Molecules

We present measurements of the circular dichroism of optically pumped Rb vapor near the D1 resonance line. Collisions with the buffer gases $^3$He and N$_2$ reduce the transparency of the vapor, even when fully polarized. We use two methods to measure this effect, show that the He results can be understood from RbHe potential curves, and show how this effect conspires with the spectral profile of the optical pumping light to increase the laser power demands for optical pumping of very optically thick samples

Effects of Quasi-Static Aberrations in Faint Companion Searches

We present the first results obtained at CFHT with the TRIDENT infrared camera, dedicated to the detection of faint companions close to bright nearby stars. The camera's main feature is the acquisition of three simultaneous images in three wavelengths (simultaneous differential imaging) across the methane absorption bandhead at 1.6 micron, that enables a precise subtraction of the primary star PSF while keeping the companion signal. The main limitation is non-common path aberrations between the three optical paths that slightly decorrelate the PSFs. Two types of PSF calibrations are combined with the differential simultaneous imaging technique to further attenuate the PSF: reference star subtraction and instrument rotation to smooth aberrations. It is shown that a faint companion with a DeltaH of 10 magnitudes would be detected at 0.5 arcsec from the primary.Comment: 12 pages, 10 figures, to appear in Astronomy with High Contrast Imaging, EAS Publications Serie

Dynamics of the nighttime thermosphere at Arecibo

Incoherent scatter radar observations of the nighttime F layer at Arecibo, Puerto Rico, are used to determine the O+ diffusion velocity at different altitudes. Further analysis allows evaluation of the neutral wind and the ion-drag force in the direction of the magnetic meridian. The local acceleration of the meridional neutral wind is also determined. The possibility of evaluating the viscous force using incoherent scatter radar data was also investigated. Preliminary results indicate that, at certain times and at altitudes above about 350 km, viscous drag may be a significant term in the neutral equation of motion. Combining these results allows height profiles of the meridional pressure gradient to be deduced. The pressure gradients thus derived is compared with that determined from measurements of the horizontal temperature gradient and that given by the MSIS model atmosphere