Astronomy and Astrophysics Supplement Series

https://aas.aanda.org/

List of Papers (Total 1,649)

Construction of the Tycho Reference Catalogue

The Tycho Reference Catalogue (TRC) project, as proposed in 1992 by the present authors, aimed to extend the Hipparcos reference system to fainter magnitudes. To assure rigidity of the reference system realization, the project relied on the Tycho Cataloguethat provides highly-accurate positions of more than one million stars on the Hipparcos system. To maintain the precision of...

Star formation in the Vela Molecular Clouds - III. Near IR images and mm photometry of D-cloud IRAS sources

We present the first results of a sensitive ( 17 mag) near IR (JHK) imaging survey of a complete IRAS selected sample of Young Stellar Objects (YSO's) belonging to a Giant Molecular Cloud (GMC) located in the Vela Molecular Ridge (VMR). We provide accurate position and photometry for more than 1300 sources, along with the identification of possible NIR counterparts of the IRAS...

1994-1996 CCD astrometric observations of Saturn's satellites and comparison with theories

In this paper, we publish 451 measurements of positions of the major satellites of Saturn made in 1994, 1995 and 1996 using a CCD detector attached to the 1.56 m reflector at the Sheshan Station near Shanghai. The observations we have made include the seven major satellites exclusive of the outermost satellite Iapetus. In our implementation the four contemporary theories were...

Understanding A-type supergiants - I. Ultraviolet and visible spectral atlas of A-type supergiants

This paper is the first of a series whose aim is to perform a systematic study of A-type supergiant atmospheres and winds. Here we present a spectral atlas of 41 A-supergiants observed by us in high and medium resolution in the visible and ultraviolet. The atlas consists of profiles of the Hα, Hβ, Hγ, Hδ, Hϵ, Ca II (H and K), Na I (D1 and D2), Mg II 4481, Mg II [uv1] and Fe II...

Phase calibration scheme for a "T” array

A calibration scheme based on closure and redundancy techniques is described for correcting the phase errors in the complex visibilities observed with a T-shaped radio interferometer array. Practical details of the scheme are illustrated with reference to the Gauribidanur radioheliograph (GRH).

Hydrogen content in Kazarian galaxies

Several H I related astrophysical parameters such as neutral hydrogen total mass and hydrogen mean projected density, indicative total mass as well as usual ratios , and for 23 galaxies from Kazarian lists are derived. Their variation ranges are rather wide almost coinciding with those for normal galaxies belonging to the same morphological types. Kazarian galaxies do not...

A survey of UV-excess AGNs in the South Galactic Pole - A sample for the analysis of the QSO clustering

Spectra, position, magnitudes and colors are presented for 485 faint () emission line objects selected with the ultraviolet-excess (UVX) criterion on a area of 24.6 deg2 in the South Galactic Pole. The objects were selected from the analysis of pixel-to-pixel stacking of COSMOS scans of UKST U J and R plates. The candidates were observed with the Meudon-ESO Fiber Optics System...

Contribution à l'étude des spectres composites - VIII. HD 174016-7, une étoile Ap associée à une géante G Contribution to the study of composite spectra VIII. HD 174016-7, an Ap star with a giant G

HD 174016-7, listed by [Hynek (1938)] as a star having a composite spectrum, was on our observing programmes of such objects carried out both at the Cambridge Observatories and at the Observatoire Midi-Pyrénées. Most of the observations were made with the CORAVEL spectrovelocimeter of the Swiss telescope at the Observatoire de Haute-Provence. We find that this star is a long...

The effective temperature scale of giant stars (F0–K5) - II. Empirical calibration of versus colours and [Fe/H]

We present calibrations of the effective temperatures of giant stars versus [Fe/H] and colours , , , , , , , , , , and . These calibrations are based on a large sample of field and globular cluster stars which roughly cover spectral types from F0 to K5. Their effective temperatures, scaled to direct determinations via reliable angular diameter measurements, were derived by...

An absolute calibration of DENIS (deep near infrared southern sky survey)

An absolute calibration of the DENIS photometric system is presented. It includes the determination of the overall transmission profiles in the 3 bands, namely i, J and Ks, combining contributions from atmosphere, telescope mirrors, instrument lenses and dichroics, filters, and detectors. From these normalized profiles, isophotal and effective wavelengths are computed, using the...

Interferometric imaging tests for the Large Binocular Telescope

We present an experiment of interferometric imaging for the Large Binocular Telescope (LBT), conducted at the 1.5 m TIRGO infrared telescope. The raw data were produced by simulating the LBT pupil with a mask on the secondary mirror. Two different conditions of , where is the single aperture diameter and the Fried parameter, were simulated by the choice of ; field rotation was...

HI observations of nearby galaxies - I. The first list of the Karachentsev catalog

We present HI observations of the galaxies in the first list of the Karachentsev catalog of previously unknown nearby dwarf galaxies (Karachentseva & Karachentsev 1998). This survey covers all known nearby galaxy groups within the Local Volume (i.e. within 10 Mpc) and their environment, that is about 25% of the total sky. A total of 257 galaxies have been observed with a...

Estimating the point spread function of the adaptive optics system ADONIS using the wavefront sensor measurements

Adaptive Optics (AO) has been developed to compensate the wavefront deformation due to the atmospheric turbulence. The wavefront correction, however, is often only partial and a residual blur is present in a long exposure image. It is therefore important to deconvolve the image to do accurate photometry or to detect faint structures. For this, the point spread function (PSF) has...

Relative figure of merit of optical interferometry and spectroscopy - Example of parameter estimates of P Cygni circumstellar envelope

When planning new facilities, one is interested to know whether and by how much the new technique is superior to already existing ones. We describe a general approach permitting us to evaluate the relative merits of various techniques used in astrophysical observations, following the theory of model parameter estimation. It is applied to compare two-aperture optical long baseline...

The ionized gas in the spiral galaxy NGC 3359 - II. Kinematics

The spiral galaxy NGC 3359 has been observed in the Hα line with the TAURUS II Fabry-Perot interferometer at the William Herschel Telescope within the BARS programme on the Canary Island telescopes in order to study the kinematics of the ionized gas.
We have produced maps of velocity and velocity dispersion, and computed the rotation curve out to ~ 3 scale lengths from the centre...

A list of data for the broadening of metallic lines by neutral hydrogen collisions

A list of data for the broadening by neutral hydrogen collisions of many astrophysically important spectral lines, which has been incorporated into the Vienna Atomic Line Database (VALD), is presented. Data for lines of neutral atoms are interpolated from the tabulated data of Anstee & O'Mara (1995), Barklem & O'Mara (1997), and Barklem et al. (1998). Data for lines of singly...

Optical polarization of 47 quasi-stellar objects: The data

New broad-band linear polarization measurements are presented for a sample of 47 QSOs which includes 27 broad absorption line QSOs and 2 gravitational lens candidates.

Search and discovery tools for astronomical on-line resources and services

A growing number of astronomical resources and data or information services are made available through the Internet. However valuable information is frequently hidden in a deluge of non-pertinent or non up-to-date documents. At a first level, compilations of astronomical resources provide help for selecting relevant sites. Combining yellow-page services and meta-databases of...

Micrometer measurements of double stars made at the Côte D'Azur and Calar Alto observatories

We report 312 micrometer measurements of 155 visual double stars made with the 50 cm refractor at the Côte D'Azur observatory (Nice, France) and with the 152 cm telescope at Calar Alto observatory (Almería, Spain).

Atomic data from the IRON Project - XLII. Electron impact excitation of Fe xxi

Collision strengths and collisional rate parameters are provided for transitions among the and 2p levels of C-like Fe xxi. The data have been computed in a 52-state Breit-Pauli approximation thus accounting for the most prominent relativistic effects. An R-matrix close-coupling calculation comprising partial wave contributions up to and of order 8000 energy points in the range up...

Tuorla quasar monitoring

We present results of optical monitoring of quasars and blazars obtained at Tuorla Observatory between September 1995 and May 1997. The aim of our monitoring is to provide well sampled optical light curves for quasar and blazar studies. During the observing period the V-band brightness of S2 0109+224, 3C 66A, and ON 231 (W Comae) reached some of the brightest values ever measured...

Hipparcos astrometry for 257 stars using Tycho-2 data

We present improved Hipparcos astrometry for 257 Hipparcos stars, resolved into 342 components. For 64 of the stars no astrometry was obtained in the Hipparcos Catalogue, while for the remaining stars additional components have been added by this solution or the positions have been revised considerably. We have used the published Hipparcos transit data for the new solutions...

Polarization for pair annihilation in strong magnetic fields

We derive the cross-section for one-quantum annihilation of polarized electrons and positrons. The electron and positron can occupy arbitrary Landau levels and have non-zero momentum parallel to the field, and the cross-section is calculated for any polarization of the radiation. When we take zero parallel momentum for the electron and sum over photon polarization we obtain...

A revised catalogue of δ Sct stars

An extensive and up-dated list of δ Sct stars is presented here. More than 500 papers, published during the last few years, have been revised and 341 new variables have been added to our last list, six years ago. This catalogue is intended to be a comprehensive review on the observational characteristics of all the δ Sct stars known until now, including stars contained in earlier...

Strömgren and Hβ photometry of O and B type stars in star-forming regions - III. Carina Spiral Feature

Strömgren and Hβ photometry of O and B type stars, generally brighter than 9.5 mag is reported for the field of the Carina Spiral Feature. The observations are based on the PPM catalogue identifications and are designed to improve the completeness of the existing data for the bright early-type stars in the field. We present new uvby photometry for 283 stars and Hβ photometry for...