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Kinematical Structure of Wolf-Rayet Winds. II. Internal Velocity Scatter in WN Stars

Niedzielski, A.; Nugis, T.; Skorzynski, W.

The shortward edge of the absorption core velocities - v_black as determined from low resolution archived IUE spectra from the INES database are presented for three P Cyg profiles of NV 1240, HeII 1640 and NIV 1720 for 51 Galactic and 64 LMC Wolf-Rayet stars of the WN subtype. These data, together with v_black of CIV 1550 line presented in Niedzie…

X-Ray Emission from the Warm-Hot Intergalactic Medium

Kaastra, Jelle S.

Visualization and topographical analysis of the Mars surface

Dorninger, P.; Jansa, J.; Briese, Ch.

The Institute of Photogrammetry and Remote Sensing has more than 30 years of experience in computation, visualization and analysis of digital terrain data. Most of the developed methods and algorithms are implemented in the software application SCOP++ and tested on Earth datasets. Due to the institute's involvement into Mars Express, these methods…

The distance to NGC 5904 (M 5) via the subdwarf main sequence fitting method

Testa, V.; Marconi, G.; Andreuzzi, G. +2 more

We present a determination of the distance modulus of the globular cluster NGC 5904 (M 5), obtained by means of the subdwarf main-sequence fitting on the (V,V-I) color-magnitude diagram. The subdwarf sample has been selected from the HIPPARCOS catalog in a metallicity range homogeneous with the cluster ([Fe/H] ≃ -1.1). Both the cluster and the sub…

The Pattern of Moving Magnetic Inhomogeneities in and Around Sunspots

Venkatakrishnan, P.; Kumar, Brajesh; Ravindra, B.

High-resolution MDI magnetograms are used to study the pattern of moving magnetic inhomogeneities in sunspots. We examine the inward and outward moving features in sunspots. The velocity of these features is small in the umbra while it is about 0.5 km s⁻¹ in the outer penumbra. The inward and outward moving features may be the possible …

The Counterarc to MS 1512-cB58 and a Companion Galaxy

Teplitz, Harry I.; Malkan, Matthew A.; McLean, Ian S.

We present near-infrared spectra of ``A2,'' the primary counterarc to the gravitationally lensed galaxy MS 1512-cB58. The spectra show redshifted Hα, [N II], [O III], and Hβ at z=2.729+/-0.001. We observe the same Hα/[O III] ratio as cB58, which together with the redshift confirms that A2 is indeed another image of a single background galaxy. Publ…

Excess facular emission from an isolated active region during solar minimum: the example of NOAA AR 7978

Sanahuja, B.; Fröhlich, C.; Ortiz, A. +1 more

The facular contribution to solar irradiance variations on the short time scale is studied by analyzing a simple case of an isolated active region that crossed the solar disk during the 1996 minimum of activity, NOAA AR 7978. Its passage during several Carrington rotations, specifically from rotation 1911 to 1916, allows us to analyze the evolutio…

Properties and nature of Be stars. XXII. Long-term light and spectral variations of the new bright Be star HD 6226

Buil, C.; Harmanec, P.; Yang, S. +8 more

Photometric and spectroscopic monitoring of the B star HD 6226 resulted in the finding that this object is a new bright Be star with a clear positive correlation between the brightness and emission-line strength. The emission-line episodes are relatively short and seem to repeat frequently which makes this star an ideal target for studying the cau…

Monte Carlo simulations of CASSINI/LEMMS

Livi, S.; Haggerty, D. K.

In an effort to characterize the response of the low energy magnetospheric measurements system (LEMMS) on the CASSINI spacecraft to energetic ions and electrons we have taken advantage of the excellent pre-launch beam calibrations in comparison to an extensive series of electron and ion Monte Carlo simulations. We selected the geometry and trackin…

Faint 6.7 Micron Galaxies and Their Contributions to the Stellar Mass Density in the Universe

Matsuhara, Hideo; Cowie, Lennox L.; Taniguchi, Yoshiaki +6 more

We discuss the nature of faint 6.7 µm galaxies detected with the mid-infrared camera ISOCAM on board the Infrared Space Observatory (ISO). The 23 hr integration on the Hawaii Deep Field SSA13 has provided a sample of 65 sources down to 6 µJy at 6.7 µm. For 57 sources, optical or near-infrared counterparts were found using a stati…