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Magnetized vortex tubes in the solar wind plasma

Moussas, X.; Polygiannakis, J. M.

We make new applications of our previously proposed method for estimating the strain-rate tensor and vorticity vector in plasmas (concerning the local deformation and self rotation of the plasma fluid elements, respectively) solely from magnetic field time series. Here we use solar wind measurements of Ulysses spacecraft made in the outer heliosph…

Contribution à l'étude des binaires des types F, G, K, M. VIII. HD 195850 et HD 201193, binaires spectroscopiques à raies doubles Contribution to the study of F, G, K, M binaries. VIII. HD 195850 and HD 201193, double-lined spectroscopic binaries

Ginestet, N.; Carquillat, J. M.

Radial-velocity observations of the double-lined spectroscopic binaries HD 195850 and HD 201193 have been carried out at the Observatoire de Haute-Provence with the CORAVEL instrument in order to determine their orbital elements. They are as follows HD 195850: P = 37.94106 days; T = 2444872.24 HJD; omega = 111^o 5 ; e = 0.185; K_1 = 34.1…

Tidal Structures of z ~ 1 Galaxies in the Hubble Deep Field

Reshetnikov, V. P.

An analysis of the images of objects in the Northern Hubble Space Telescope Deep Field has revealed twelve galaxies with tidal tails at redshifts from 0.5 to 1.5. The integrated characteristics of the newly discovered tidal structures are found to be similar to those of the tails of local interacting galaxies. The space density of galaxies with ti…

Alfvénicity of fluctuations associated with the Kelvin-Helmholtz instability

Suess, S. T.; Parhi, S.

The velocity shear which exists between three layers in an ideal plasma is studied. This configuration is modeled as a jet (or, strictly speaking, a wake) embedded in a uniform medium using a magnetohydrodynamics (MHD) code developed for astrophysical jet simulations. Weak and strong magnetic fields are considered both inside and outside the jet w…

High-Resolution Near-Infrared Imaging of the Powerful Radio Galaxy 3C 324 at z = 1.21 with the Subaru Telescope

Terada, Hiroshi; Usuda, Tomonori; Imanishi, Masatoshi +18 more

We have obtained high-resolution K^'-band images of the powerful z=1.206 radio galaxy 3C 324 with the Subaru telescope under seeing conditions of 0.^''3-0.^''4. We clearly resolved the galaxy and directly compared it to the optical images obtained with the Hubble Space Telescope. The host galaxy of 3C 324 is revealed …

Rotational modulation of the ultraviolet line fluxes from the RS CVn star II Pegasi

Sarro, L. M.; Byrne, P. B.

The exceptional in-orbit performance of the International Ultraviolet Explorer (IUE) for more than eighteen years has made it possible to accumulate an invaluable database of ultraviolet observations of a wide variety of objects and, in particular of active stars. \citeN{BS98} -hereafter Paper I- have presented a multiwavelength campaign of observ…

The Magnetic Connectivity of Moss Regions

Kosovichev, A. G.; Hoeksema, J. T.; Scherrer, P. H. +2 more

A novel emission feature resembling moss was first identified in high-resolution TRACE Fe ix/x 171 Å images by Berger et al. (1999). The moss emission is characterized by dynamic arc-second scale, bright elements surrounding dark inclusions in images of solar active regions. Patches of moss elements, called moss regions, have a scale of 20-30 Mm. …

Separation between Gould Belt and Disk Stars in the Solar Neighbourhood

Alfaro, E. J.; Cabrera-Caño, J.; Elias, F.

The adoption of a parametric model for the spatial distribution of Gould Belt and Galactic Disk stars allows the classification by their membership probabilities of stars from the Hipparcos catalogue in the Solar vicinity and the estimation of structural parameters for both stellar systems for several age groups. The observed kinematics of Gould B…

Molecular gas and star formation in the host galaxy of I Zw 1

Schinnerer, Eva; Eckart, Andreas; Tacconi, Linda

A recent analysis of high angular resolution NIR imaging and spectroscopic data in conjunction with Plateau de Bure interferometric mm-line observations indicate the presence of a circum-nuclear starburst ring of ∼1.5″ (1.5 kpc) diameter in I Zw 1. High angular resolution NIR imaging, using the MPE SHARP camera at the ESO NTT, HST V-band images, a…

Measurement and Modeling of Solar EUV/UV Radiation

Tobiska, W. K.