An uncatalogued optical HII region at the outskirts of the Galaxy

We present NOT optical observations of a clump (l = 127.9435 deg, b = +1.8298 deg), embedded in an extended, irregularly shaped, diffuse optical nebula. This condensation shows an emission-line spectrum typical of classic HII regions. Although its location on the sky coincides with a nearby extended photoionized region recently identified by Cichowolski et al. (2003) in radio data from the Canadian Galactic Plane Survey (CGPS), the systemic velocity of this ~ 1 arcmin-sized HII region, V_LSR = -71$\pm$12 km/s, poses it far out in the Galaxy, beyond the Perseus arm. The location of this region in the Galaxy is supported by HI structures visible at comparable radial velocity on CGPS data. We argue that this HII region might belong to an outer Galactic arm. The emission line ratios of the surrounding extended nebula, whose radial velocity is consistent with that of the small HII region, are typical of photoionized gas in the low density limit. Smaller clumps of comparable surface brightness are visible within the optical boundaries of the extended, faint nebula. After comparison of the optical data with far infrared and radio observations, we conclude that this nebula is an HII region, ~ 70 pc in size, probably photoionized by an association of OB stars and surrounded by a ring of neutral hydrogen.Comment: 8 pages, 9 figures (some of which degraded due to size constraints), accepted on 2004/02/12 for publication in Astronomy and Astrophysic

Densification of powder metallurgy billets by a roll consolidation technique

Container design is used to convert partially densified powder metallurgy compacts into fully densified slabs in one processing step. Technique improves product yield, lowers costs and yields great flexibility in process scale-up. Technique is applicable to all types of fabricable metallic materials that are produced from powder metallurgy process

Particle dislodgement and entrainment by a low density airstream flowing over a surface

Dislodgement and entrainment of solid particles by low density airstream flowing over particulate surface, for aerodynamic surface erosion stud

Evaluation of the optical conductivity tensor in terms of contour integrations

For the case of finite life-time broadening the standard Kubo-formula for the optical conductivity tensor is rederived in terms of Green's functions by using contour integrations, whereby finite temperatures are accounted for by using the Fermi-Dirac distribution function. For zero life-time broadening, the present formalism is related to expressions well-known in the literature. Numerical aspects of how to calculate the corresponding contour integrals are also outlined.Comment: 8 pages, Latex + 2 figure (Encapsulated Postscript

Coseismic horizontal slip revealed by sheared clastic dikes in the Dead Sea Basin

Peer reviewedPostprin

Planetary environment simulation - Martian sand and dust storm simulation and evaluation, volume 2

Particle behavior in simulated Martian sand and dust stor

A pair of gigantic bipolar dust jets close to the solar system

We report the discovery of two adjacent jet candidates with a length of about 9 degrees each -- 10 times longer than the largest known jets -- detected by us on 60 and 100 micron IRAS maps, but not observed at any other wavelength. They are extremely collimated (length-to-width ratios 20--50), curved, knotty, and end in prominent bubbles. Their dust temperatures are 25 K and 30 K, respectively. Both harbour faint stars, one having a high proper motion (0.23 arcsec/yr) and being very red, suggesting a distance of about 60 pc. At this distance, the total mass of both jet candidates is about about 1 solar mass. We suspect that these gigantic (9 pc length respectively) jets are of fossil type and have a common origin, due to the decay of a system of evolved stars. They are the first examples of jets radiating in the far IR and might, because of their closeness, be of interest for further studies of the acceleration and collimation processes of astrophysical jets.Comment: 4 pages, 4 figures in reduced quality, accepted by Astronomy & Astrophysics (Letter) february 10, 2004. See http://astro.uibk.ac.at/dustjets/ for the full resolution and color version of the image