A major goal in solar physics has during the last five decades been to find how energy flux generated in the solar convection zone is transported and dissipated in the outer solar layers. Progress in this field has been slow and painstaking. However, advances in computer hardware and numerical methods, vastly increased observational capababilities and growing physical insight seem finally to be leading towards understanding. Here we present exploratory numerical MHD models that span the entire solar atmosphere from the upper convection zone to the lower corona. These models include non-grey, non-lte radiative transport in the photosphere and chromosphere, optically thin radiative losses as well as magnetic field-aligned heat conduction in the transition region and corona.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

We present the initial results of our analysis of line emission produced in gas disks found at the centers of a sample of nearby radio galaxies with radio jets. We obtained data using STIS (The Space Telescope Imaging Spectrograph) at three parallel slit positions on the nucleus of each galaxy. This allows us to map the Hα + [NII] flux, the gas radial velocity and the velocity dispersion. We found that we cannot rule out a rotating disk model for the gas in any case. We found that for 62% of the galaxies the fit is improved in the nucleus by the inclusion of an additional broad component. By comparing the observed central kinematics to model gas disks we were able to estimate the masses of nuclear black holes in 12 of the sample galaxies.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

We derived the chemical abundances in the photosphere of $\delta$ Scuti, the prototype of the class of pulsating variables, from the analysis of a spectrum obtained at the Terskol Observatory 2-m telescope with a resolution $R=52000$ and $S/N=250$. VLT and IUE spectra were also used. The abundance pattern of $\delta$ Sct consists of 49 chemical elements. The abundances of Be, P, Ge, Nb, Mo, Ru, Er, Tb, Dy, Tm, Yb, Lu, Hf, Ta, Os, Pt, and Th were not investigated previously. The lines of third spectra of Pr and Nd also are investigated for the first time. The abundances of heavy elements show overabundances with respect to the Sun up to 1 dex. The abundance pattern of $\delta$ Sct is similar to that of the Am-Fm stars.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

Recent observational work has shown that the emission in different layers of the solar atmosphere can de described statistically. For example, Pauluhn et al. (2000) show that the frequency distribution of quiet Sun emission in EUV lines is well fit by a lognormal distribution. In addition, Parnell (2002) has shown that the frequency distribution of discrete magnetic elements in the quiet Sun is well fit by a Weibull distribution. These distributions arise naturally from fragmentation studies of materials such as polymers and sediments. It is suggested that fragmentation and its related phenomena may be of use in describing the physics of how the above distributions appear on the Sun.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

Recent spectroscopic observations of roAp stars with high spectral resolution and high time resolution show line profile variations (LPV) which seem to be similar to those seen in rapidly rotating B-type line-profile variables. At first glance these line profile variations seem to be in disagreement with the mode identification based on the photometric observations. We propose an interpretation according to which the observed line profile variations are a manifestation of a shock wave in the high atmosphere near the magnetic polar regions, and show that the line profile variations can be still understood in the framework of the oscillation mode being consistent with the photometric observations.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

We have carried out aperture synthesis CO(J=1-0) observations of the FRI radio galaxy 3C 31 (NGC 383), using the Nobeyama Millimeter Array (NMA) and the RAINBOW interferometer, which achieves a large collecting area by adding the NRO 45m telescope. Our high-resolution (1.9″×1.4″) CO 3D observations reveal a very massive ($\sim 10^9 M_\odot$), circularly-rotating molecular gas ring, which coincides nicely with the silhouette disk seen in the Hubble Space Telescope (HST) optical images. This is the first map depicting the molecular gas distribution and kinematics associated with a silhouette disk in the heart of a radio galaxy.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

We made observations of the LINER NGC 7213 in order to perform critical procedures in observing with the Eucalyptus IFU spectrograph. This object has emission lines with stellar profiles surrounded by weak extended nebular emission. We obtained narrow bands images and space resolved spectra, which suggest the existence of a bar of stellar origin.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

Changes of extreme ultraviolet (EUV) Solar flux were registered during the Annular Solar eclipse of May 31 2003, when CORONAS-F satellite (Oraevsky et al., 2002) intersected thrice a zone of the Solar eclipse. During these periods the solar emission was measured in visible and extreme UV spectral regions (near $L_{\alpha} = 121.6$ nm by VUSS instrument). Records by VUSS ($\sim 120$ nm) and the optical (visible) channel of EOS instruments on UTC scale for May 31, 2003 are given on Fig. 1.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

DG Leo is a spectroscopic triple system showing $\delta$ Scuti type photometric and spectroscopic variations. The three components have nearly equal masses but different chemical compositions in the outer layers. All three are potential pulsators. Frequency analyses of the photometric data were carried out using various methods. These global results together with those of the spectroscopic analysis permit us to discuss of the behaviour of each component with respect to pulsation.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

We present a novel method, based on the Doppler imaging inversion technique, which tries to construct a two-dimensional ‘image’ of the pulsation velocity field using time series observations of stellar spectra. This method is applied to study the geometry of nonradial oscillations in the roAp star HR 3831. The image of pulsational perturbations at the surface of this star is the first stellar pulsation map derived without assuming the spherical harmonic formalism. Our Doppler reconstruction directly demonstrates an alignment of the roAp pulsations with the stellar magnetic field axis. It also reveals a significant distortion of the dominant oblique $\ell=1$ oscillation mode by the stellar magnetic field. This first detailed characterization of the magnetic and rotation effects on pulsations opens possibilities for the direct testing of recent theories of magnetoacoustic oscillations in roAp stars.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

AGN activity is known to drive fast outflows of gas. We report the discovery of fast outflows of neutral gas with velocities over 1000 km/s in a number of radio galaxies. In the best studied object, 3C 293, the kinematical properties of the neutral and ionised outflows are similar, indicating a common origin. Moreover, the outflow appears to be located near the radio lobes and not near the nucleus. This suggests that the interaction between the radio jet and the ISM is driving the outflow.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

On the basis of an analogy between solar and stellar flares the optical oscillations with periods of tens of seconds observed on the EV Lac are analyzed. In terms of the diagnostic tool proposed by Zaitsev & Stepanov (1982) the main parameters of the flare loop was obtained. We concluded that source of the optical radiation is located at the loop footpoints and its pulsations are determined by the modulation of the flux of energetic particles.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

The existence of Maia variables has been in dispute since 1955. They are supposed to be located between the blue edge of the classical instability strip and the red border of the slowly pulsating B stars, hence in a domain of the HRD where no excitation mechanism for pulsation is yet known. But luminosity variations were discovered in time series of $\alpha$ Draconis, an A0III Maia candidate star, with a period of about 53 minutes and an amplitude of less than 0.002 mag. Spectroscopic time series indicate radial velocity variations with the same period and an amplitude of about $40{\rm m\,s}^{-1}$. Alpha Dra is a single-lined spectroscopic binary with an orbital period of 51.4 days and a distance between the components of about 0.46 AU. Tidal interaction may therefore be responsible for pulsation. If true, the pulsation amplitude should be modulated with the orbit as is indeed indicated by recent observations.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

Four series of coronal images have been obtained by the expedition of Abastumani Astrophysical Observatory during the August 11, 1999 total solar eclipse with the help of the photographic mirror-lens polarimeter (D=150 mm, F=1000 mm). Each series includes three images corresponding to three positions of the polarization analyzer. The position of the solar disk center relative to the Moon's center has been determined beforehand. In addition, the background skylight polarization and intensity are calculated. All measurements are absolute given in units of the sun's average surface brightness. Equatorial electron densities and temperatures are determined. Our data are compared with previous absolute measurements.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

We present a study of the emission line profiles of a sample of 12 single-peaked Active Galactic Nuclei (AGNs- Sy 1 and QSOs). The narrow [OIII] lines seem to be related to two components; NLR1, which has dispersion velocities from 200 to 500 km s−1 and is blueshifted with respect to the systemic by about 20 to 350 km s−1; and NLR2, with smaller dispersion velocities (∼100-200 km s−1) and a redshift corresponding to the cosmological one. The broad lines have complex structure and a two-component model has been applied.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

In addition to revealing spherical harmonic degrees, $\ell$, of excited modes, pulsational amplitudes and phases from multicolour photometry and radial velocity data yield valuable constraints on stellar atmospheric parameters and on subphotospheric convection. Multiperiodic pulsators are of particular interest because each mode yields independent constraints. We present an analysis of data on the twelve modes observed in FG Vir.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

In this paper we interpret C and X-band radio continuum observations of a sample of Markarian galaxies. The results are briefly discussed. Seyfert 2 galaxies show sistematically higher HI mass-to-blue magnitude than Seyfert 1 galaxies, as well as higher radio to far-infrared luminosities. The observational properties are interpreted in terms of simple non-thermal and dust emission. We obtained radio brightness temperatures, equipartion magnetic fields and total magnetic densities for the disks. Upper limits for thermal densities are derived from simple free-free emission. Star formation rates and mean supernova rates are estimated for individual Markarian galaxies. The SFR values of the most luminous Markarian galaxies are considerably higher than those found in compact blue dwarf galaxies and also in gas-rich, early-type spirals.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

We present a method how to describe analytically a magnetic field distribution in the vicinity of a large interplanetary flux rope. The field consists of the pre-existing one and an additional current-free part. This work was supported by INTAS grant 03-51-6206, AV ČR project S1003006, and RFBR grant 03-02-16340.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

Based on a preliminary analysis of 3 nights of high-dispersion spectral observations of HD 101065 (Przybylski's star) obtained on the ESO 3.6-m telescope + HARPS we find rapid multiperiodic radial velocity oscillations of at least three pulsation modes. The detailed analysis of the frequency space and probable splitting based on 4 nights of data will be given later.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

In this paper we present some preliminary results of a 3-mm (86 GHz) radio continuum survey of selected Seyfert galaxies made with the Berkley-Maryland Illinois Millimeter Array (BIMA) in D configuration. The images shown here have spatial resolutions of about two arcminutes after gaussian tapering. At this observing wavelength, we expect to have a negligible non-thermal emission as the spectra is certainly dominated by free-free radio emission. We have measured flux densities and 3 mm luminosities which agree with a thermal blackbody spectra expected from data obtained with the IRAS satellite at wavelengths shorter than 80 μm. Data is presented for NGC3982, NGC5597, NGC5253, NGC1667, and NGC2997 and the main astrophysical consequences of such studies are discussed in this poster. We also argue that radio continuum at millimeter wavelengths is a better observational tool to study the star-formation in active galaxies than conventional infrared photometry.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html