Search Publications

ISO SWS-LWS observations of the prototypical reflection nebula NGC 7023
DOI: 10.48550/arXiv.astro-ph/0001155 Bibcode: 2000A&A...354.1053F

Cernicharo, J.; Gerin, M.; Fuente, A. +2 more

We present SWS and LWS ISO observations towards a strip across the photodissociation region (PDR) in the reflection nebula NGC 7023. SWS02 and LWS01 spectra have been taken towards the star and the brightest infrared filaments located NW and SW from the star (hereafter NW and SW PDRs). In addition, SWS02 spectra have been taken towards two interme…

2000 Astronomy and Astrophysics
ISO 38
Ultraviolet fluorescence lines of Fe II observed in satellite spectra of the symbiotic star RR Telescopii
Bibcode: 2000A&A...359..627H

Johansson, S.; Hartman, H.

By examining all emission lines of Fe II in high resolution satellite spectra of the symbiotic star RR Tel we have made a systematic study of fluorescence lines in the ultraviolet wavelength region 1200-3000 Ä. We list 33 energy levels of Fe II that are selectively excited in the stellar system by photons from strong lines of H, He II, Si III, O I…

2000 Astronomy and Astrophysics
IUE eHST 37
Ca II activity and rotation in F-K evolved stars
DOI: 10.48550/arXiv.astro-ph/0008109 Bibcode: 2000A&A...361.1011P

Pasquini, L.; de Medeiros, J. R.; Girardi, L.

Ca II H and K high resolution observations for 60 evolved stars in the field and in 5 open clusters are presented. From these spectra chromospheric fluxes are derived, and a homogeneous sample of more than 100 giants is built adding data from the literature. In addition, for most stars, rotational velocities were derived from CORAVEL observations.…

2000 Astronomy and Astrophysics
Hipparcos 37
Spectropolarimetric measurements of the mean longitudinal magnetic field of chemically peculiar stars. On the light, spectral and magnetic variability
Bibcode: 2000A&A...355..315L

Leone, F.; Catalano, S.; Catanzaro, G.

We have equipped the spectrograph of the Catania Astrophysical Observatory with a polarimetric module which gives simultaneous circularly right and left polarised radiation spectra. This facility has been used to perform time-resolved spectropolarimetric (Stokes V) measurements of the mean longitudinal (effective) magnetic field for seven chemical…

2000 Astronomy and Astrophysics
Hipparcos 37
Near-infrared photometry of isolated spirals with and without an AGN --- II. Photometric properties of the host galaxies
DOI: 10.48550/arXiv.astro-ph/0006247 Bibcode: 2000A&A...360..431M

Roth, M.; Durret, F.; González Delgado, R. M. +6 more

We present here the analysis of morphological and photometric properties of a sample of isolated spirals with (18) and without (11) an active nucleus, based on near-infrared imaging in the J and K' bands (Paper I). The aim of that comparative analysis is to find the differential properties that could be directly connected with the phenomenon of nu…

2000 Astronomy and Astrophysics
eHST 37
Radiance variations of the quiet Sun at far-ultraviolet wavelengths
Bibcode: 2000A&A...354L..71S

Wilhelm, K.; Schühle, U.; Lemaire, P. +2 more

We have measured the radiance of quiet-Sun areas at the centre of the solar disk using the vacuum-ultraviolet telescope-spectrograph SUMER (Solar Ultraviolet Measurements of Emitted Radiation) on the Solar and Heliospheric Observatory (SOHO). The radiances of selected emission lines have been measured from March 1996 to the present. The lines that…

2000 Astronomy and Astrophysics
SOHO 36
The multiple system LHS 1070: a case study for the onset of dust formation in the atmospheres of very low mass stars
Bibcode: 2000A&A...353..691L

Hauschildt, Peter H.; Richichi, Andrea; Leinert, Christoph +1 more

LHS 1070 (other common name: GJ 2005) is a nearby multiple system consisting of very low mass red dwarfs. We present the results of WFPC2 photometry and FOS spectroscopy for the three optically resolved components of this system acquired during HST cycle 5. These show (1) absolute brightnesses corresponding to…

2000 Astronomy and Astrophysics
eHST 36
Multi-wavelength study of the slow ``disparition brusque" of a filament observed with SOHO
Bibcode: 2000A&A...358..728S

Schmieder, B.; Delannée, C.; Yong, Deng Yuan +2 more

A mid-latitude filament was observed before and after its eruption with SOHO (EIT, SUMER, CDS and LASCO) and with ground based observatories (Meudon and Pic du Midi) in the context of a coordinated MEDOC campaign in Orsay. The eruption was followed by a large Coronal Mass Ejection well observed by LASCO. Few hours before its eruption, the filament…

2000 Astronomy and Astrophysics
SOHO 36
Anatomy of the counterrotating molecular disk in the spiral NGC 3593. 12CO(1-0) interferometer observations and numerical simulations
Bibcode: 2000A&A...363..869G

Hunt, L. K.; Combes, F.; García-Burillo, S. +2 more

This paper presents high-resolution (4arcsec x3arcsec ) interferometer observations of the inner disk of the starburst spiral NGC 3593, made in the (1-0) line of 12CO. NGC 3593 is an early-type system known to possess two counterrotating stellar disks of markedly different scale lengths and masses. The CO emission comes from a highly st…

2000 Astronomy and Astrophysics
eHST 36
The structure and momentum of multiple collimated outflows in the protoplanetary nebula Frosty Leo
Bibcode: 2000A&A...360L...9S

Sahai, R.; Bujarrabal, V.; Castro-Carrizo, A. +1 more

We have discovered multiple jet-like features in the inner regions of the protoplanetary nebula (PPN) Frosty Leo, in optical images obtained with the Hubble Space Telescope. Frosty Leo is only the second PPN (after CRL2688) and the first oxygen-rich one, to show well-focussed jets close to the equatorial plane. The nebula consists of two bright co…

2000 Astronomy and Astrophysics
eHST 35