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Near-infrared spectroscopy of PKS 1549-79: a protoquasar revealed?
We present a near-infrared (near-IR) spectrum of the nearby radio galaxyPKS 1549-79 (z= 0.153). These data were taken with the aim of testingthe idea that this object contains a quasar nucleus that is moderatelyextinguished, despite evidence that its radio jet points close to ourline of sight. We detect broad Paα emission (FWHM 1745 +/- 40 kms-1), relatively bright continuum emission, and a continuumslope consistent with a reddened quasar spectrum (3.1 < AV< 7.3), all emitted by an unresolved point source. Therefore weconclude that we have, indeed, detected a hidden quasar nucleus in PKS1549-79. Combined with previous results, these observations areconsistent with the idea that PKS 1549-79 is a young radio source inwhich the cocoon of debris left over from the triggering events has notyet been swept aside by circumnuclear outflows.
| VRI photometry of wide double stars with A- type primaries.
We are presenting VRI photometry of 93 wide visual double stars havinglate B- or A- type primaries, taken from the Annex of Double andMultiple Stars of the HIPPARCOS Input Catalogue. Spectral types havebeen estimated for most of the primaries and for the majority of thesecondaries. 40% of them probably have common origin components, forwhich we calculated photometric parallaxes and some orbital valuesestimates.
| Visual measurements of southern double stars
A double-star observing program is described which has been started atCordoba with a 30 cm refractor. Usually neglected Index Catalog ofVisual Double Stars (IDS) pairs south of -60 deg are selected forobservation, most of them having been measured only one or two timespreviously. A total of 174 micrometric observations of 78 wide pairs arepresented together with a few measurements of 9 double stars not foundin the IDS. Also reported is a list of 135 additional measurements of 26test stars. By comparison with all earlier observations, an estimate forthe personal equation has been made, which is applied in combinationwith catalogue proper motions to investigate the nature of many of thesepairs.
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Membre dels grups següents:
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Dades d'Observació i Astrometria
| Constel·lació: | Apus |
| Ascensió Recta: | 15h51m59.45s |
| Declinació: | -78°42'55.0" |
| Magnitud Aparent: | 9.141 |
| Moviment propi RA: | -5.7 |
| Moviment propi Dec: | -18.4 |
| B-T magnitude: | 9.221 |
| V-T magnitude: | 9.148 |
Catàlegs i designacions:
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