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The complex structure of low-luminosity active galactic nuclei: NGC 4579
Contini, Marcella
We have modelled the low-luminosity active galactic nucleus (AGN) NGC 4579 by explaining both the continuum and the line spectra observed with different apertures. It was found that the nuclear emission is dominated by an AGN such that the flux from the active centre (AC) is relatively low compared with that of the narrow emission-line region (NLR…
Astrophysical supplements to the ASCC-2.5. I. Radial velocity data
Scholz, R. -D.; Piskunov, A. E.; Kharchenko, N. V.
We present a catalogue of radial velocities of Galactic stars with high precision astrometric data CRVAD which is the result of the cross-identification of star lists from the General Catalog of Average Radial Velocities (GCRV) and from the homogeneous All-sky Compiled Catalogue of 2.5 Million Stars (ASCC-2.5). The CRVAD includes accurate J2000 eq…
Detection of Nitrogen and Neon in the X-Ray Spectrum of GP Comae Berenices with XMM/Newton
Strohmayer, Tod E.
We report on X-ray spectroscopic observations with XMM/Newton of the ultracompact, double white dwarf binary GP Com. With the Reflection Grating Spectrometers (RGSs), we detect the Lyα and Lyβ lines of hydrogen-like nitrogen (N VII) and neon (Ne X), as well as the helium-like triplets (N VI and Ne IX) of these same elements. All the emission lines…
Study of the vertical structure of Saturn's atmosphere using HST/WFPC2 images
Moreno, F.; Grodent, D.; Dols, V. +3 more
We have studied the vertical structure of hazes at six different latitudes (-60°, -50°, -30°, -10°, +30°, and +50°) on Saturn's atmosphere. For that purpose we have compared the results of our forward radiative transfer model to limb-to-limb reflectivity scans at four different wavelengths (230, 275, 673.2, and 893 nm). The images were obtained wi…
Properties and nature of Be stars Dra. XXIII. Long-term variations and physical properties of κ Dra.
Harmanec, P.; Hadrava, P.; Krtička, J. +9 more
We present an analysis of new spectroscopic observations of the bright Be star
New Light Curves and Orbital Solution for AM Leonis
Terrell, Dirk; Hiller, Mary E.; Osborn, Wayne
New UBVRI photometry has been obtained for the W UMa eclipsing system AM Leonis. The data have been used to derive nine times of minimum and to construct light curves. The minimum timings show that the system recently had a significant period increase. Modeling of the light curves shows AM Leo to be an overcontact system with a mass ratio of 2.51.…
Quasi-periodic emissions (15- 80 min) from the poles of Jupiter as a principal source of the large-scale high-latitude magnetopause boundary layer of energetic particle
Preka-Papadema, P.; Anagnostopoulos, G. C.; Karanikola, I. +2 more
In this study, we concentrate on the examination of the quasi-periodic behavior of 0.5-1.6 MeV(∼40-400 keV) protons (electrons) and of relativistic (>16 MeV) electrons, observed at Jupiter by two different experiments onboard Ulysses, the HI-SCALE and COSPIN, respectively, within the large-scale south duskside magnetopause boundary layer (MPBL)…
An X-ray absorption analysis of the high-velocity system in NGC 1275
Fabian, A. C.; Sanders, J. S.; Gillmon, K.
We present an X-ray absorption analysis of the high-velocity system (HVS) in NGC 1275 using results from a deep 200-ks Chandra observation. We are able to describe the morphology of the HVS in more detail than ever before. We present a Hubble Space Telescope image for comparison, and note close correspondence between the deepest X-ray absorption a…
Nuclear Stellar Populations in the Infrared Space Observatory Atlas of Bright Spiral Galaxies
Bendo, George J.; Joseph, Robert D.
To understand the nuclear stellar populations and star formation histories of the nuclei of spiral galaxies, we have obtained K-band nuclear spectra for 41 galaxies and H-band spectra for 20 galaxies in the Infrared Space Observatory's Atlas of Bright Spiral Galaxies. In the vast majority of the subsample (80%), the near-infrared spectra suggest t…
On the wave mode of subsecond pulses in the cm-range
Altyntsev, A. T.; Meshalkina, N. S.; Yihua, Yan +2 more
In this paper we determined the wave mode of subsecond pulses (SSP). We used data on pulses with a degree of polarization over 30%, with the sources located at −60 to +60 deg from the central meridian, for the period 2000-2002. The superposition of SSRT radio maps and MDI magnetograms has shown that radio SSP sources are typically located near the…