Convergence of eclipsing binary solutions

Attention is called to the fact that convergence to negligible corrections in differential corrections solutions usually can be achieved, provided that one or both of two common causes of poor convergence are recognized and properly dealt with.     

Classification of five new chondrite finds from Roosevelt County,New Mexico

Abstract— Five small, weathered meteorites recovered from Roosevelt County, New Mexico, USA, are called Roosevelt County 066–070. Based on optical microscopy and electron microprobe analysis of mafic minerals, RC 066–070 are classified as L5a chondrites. RC 068 and 069 are tentatively paired. RC 066 and RC 067 are not paired with RC 068 and RC 069. RC 066, 067 and 070 do not appear to be paired with each other or with RC 001–031.     

Perturbative inversion of geoacoustic parameters in a shallow waterenvironment

In many strategic shallow water areas, the geoacoustic properties of the sub-bottom are largely unknown. This paper demonstrates that inverse theory and measured data from a single hydrophone can be used to accurately deduce the geoacoustic properties of the sub-bottom, even when the initial background geoacoustic model is a highly inaccurate estimate. Since propagation in shallow water is very sensitive to the geoacoustic properties of the sub-bottom the inverse technique is a vitally important, practical, and inexpensive means to improve sonar performance prediction in a potentially hostile environment. To provide ground truth for the inverse technique, measured data collected during Project GEMINI were compared to the inverse solutions. Detailed, site-specific geoacoustic models were developed for two array locations and the finite-element parabolic equation (FEPE) model was used to estimate transmission loss (TL). The model estimates from FEPE compared well with the measured data and the detailed geoacoustic models were considered as “ground truth.” To test the efficacy of the technique, initial background geoacoustic models were constructed assuming no a priori information of the bottom. The resultant inverse solution was used to predict the geoacoustic properties at each of the sites. The final results were in excellent agreement with the measured data and the resulting TL estimates derived from the inverse technique were as good or better than the TL estimates obtained from the detailed, site-specific geoacoustic models     

Bi-Dimensional Spectrography at HST-Like Spatial Resolution: [OIII] Kinematics and Ionization in the NLR of NGC 1068

We present a study at HST-like spatial resolution of the gas kinematics in the innermost part of NGC 1068. This work is based on observations with the integral field spectrograph TIGER mounted on the CFH Telescope. We first derived the final spatial PSF of our data and checked its photometric integrity by comparison with two independent [OIII] HST images (FOC and WFPC2). We then performed a spatial deconvolution of the data-cube constraining the sum of the deconvolved velocity-slices to be as close as possible to the HST image. The resulting deconvolved data-cube has then a resolution similar to the HST image. It shows that the velocity distribution of the inner clouds detected with the HST differs strongly from a simple NE-SW ejection flow. We thus show that the previous interpretations of the double-peaked lines NE of the nucleus must be revisited. This revised version was published online in July 2006 with corrections to the Cover Date.     

Light scattering by an inhomogeneous spherically symmetric cometary atmosphere: Solar flux impinging on the nucleus head

The generalized Eddington approximation, obtained by the three-stream division of the radiation field, is used to compute the intensity falling on the nucleus head of a spherically-symmetric comet illuminated by parallel solar radiation.     

3.3 Millimeter limb brightening measurements during the 30 June 1973 total solar eclipse

Solar limb brightening measurements at a wavelength of 3.3 mm were made during the 30 June 1973 total solar eclipse from a site at Lake Rudolf, Kenya. The results show that at this wavelength there is a limb brightening of about 20%, occurring within one half arc min of the limb.