We present results from two Chandra/ACIS-I observations and one XMM-Newton observation of X-ray emission from the ISM and the inner radio lobes of the nearby radio galaxy Centaurus A. The ISM has an average radial surface brightness profile that is well described by a β-model profile with index β=0.40±0.04 and a temperature of k B T ISM ∼0.29 keV beyond 2 kpc from the nucleus. We find that diffuse X-ray emission is coincident with the outer half of the southwest radio lobe, and a bright X-ray enhancement is detected along the edge of the lobe. On the basis of energetic and lifetime arguments, we reject a nonthermal explanation for this emission. We model this emission as a thin, hot shell or cap of X-ray emitting plasma surrounding the radio lobe that was created by the supersonic inflation of the lobe. This plasma shell is both hotter than (k B T SH ∼2.9 keV) and greatly overpressurized relative to the ambient ISM indicating supersonic expansion. We estimate that the lobe is expanding into the ISM at approximately Mach 8.5 or 2400 km s −1 . We are not directly observing the bow shock, but rather the cooler, denser material that is accumulating ahead of the contact discontinuity. The thermal energy in the shell is a significant fraction of the thermal energy of the hot ISM, demonstrating the possibility that the hot ISM of early galaxies can be re-energized by outflows from nuclear activity.
A new electron beam source was developed according to ultrahigh vacuum design rules. It is rate controlled by means of a quadrupole mass spectrometer based flux meter. Preprogrammed and stored wobble patterns with a large frequency range prior and (for most materials) during evaporation improve the performance of operation and enable a high utilization of the material. A very stable operation is achieved by simultaneously controlling not only the power but also the power density. Long term stability, material utilization, dynamic range, minimum controllable rate and reproducibility were investigated especially for Si molecular beam epitaxy.
The Large Millimeter Telescope (LMT) 1 is a 50 m diameter millimeter-wave telescope designed for principal operation at wavelengths between 1mm and 4mm. The LMT secondary mirror will have a diameter of approximately 2.6 meters and focal ratio of .35. The purpose of this study was to implement the incoherent fringe projection technique and the spatial phase synchronous method to measure the secondary mirror mold profiling. The obtained topography is compared with the conic surface generated synthetically. We considered that mold should be hyperboloid surface with paraxial curvature of 1764.9 mm and conic constant of -1.1474. We will discuss the preliminary results where it is obtained a RMS of 0.624 cm.
In this paper, an optical design is presented for an anastigmatic telescope with back focal length corrected with exact ray tracing to eliminate spherical, coma, and astigmatism aberrations. The telescope is formed of three conical mirrors, two of them polished on the same substratum. The optical design is divided into three stages: we began the design obtaining the Gaussian parameters in a first-order solution; posteriorly, were obtained analytically the three mirrors' asphericity in a third-order design. The final design stage consists of the implementation of the Fermat's principle, the Abbe sine condition, and the Coddington equations for the exact correction for the three aforementioned aberrations.
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