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Detection of Optical Synchrotron Emission from the Radio Jet of 3C 279
Cheung, C. C.
We report the detection of optical and ultraviolet emission from the kiloparsec-scale jet of the well-known quasar 3C 279. A bright knot, discovered in archival V- and U-band Hubble Space Telescope Faint Object Camera images, is coincident with a peak in the radio jet ~0.6" from the nucleus. The detection was also confirmed in Wide Field Planetary…
The Cepheid Period-Luminosity Relation and the Maser Distance to NGC 4258
Marconi, M.; Musella, I.; Caputo, F.
In a recent paper describing Hubble Space Telescope observations of Cepheids in the spiral galaxy NGC 4258, Newman et al. report that the revised calibrations and methods for the Key Project on the Extragalactic Distance Scale yield that the true distance modulus of this galaxy is µ0,4258=29.40+/-0.09 mag, corresponding to a metri…
A new list of effective temperatures of chemically peculiar stars. III
Glagolevskij, Yu. V.
Our system of effective temperatures (paper II) is analysed by way of comparison with the Hipparcos data and the correctness of the methods of their determination is verified. With the aid of these temperatures absolute bolometric magnitudes of more than 220 CP stars have been estimated from the parameters of multicolour β and c1 photom…
The lensing system towards the doubly imaged quasar SBS 1520+530
Bolzonella, M.; Faure, C.; Alloin, D. +3 more
The gravitational potential responsible for the lensing effect in SBS 1520+530, is studied over length scales from a few arc-seconds to a few arc-minutes. For this purpose, we use sharply deconvolved Hubble Space Telescope images in the optical and near-IR, in combination with ground based optical data obtained over a wider field-of-view. In parti…
The Spatially Resolved Mass Function of the Globular Cluster M22
Albrow, Michael D.; Sahu, Kailash C.; De Marchi, Guido
Hubble Space Telescope imaging of M22 has allowed, for the first time, a detailed and uniform mapping of mass segregation in a globular cluster. Luminosity and mass functions from the turnoff down to the mid to lower main sequence are presented for M22 in annular bins from the center of the cluster out to five core radii. Within the core, a signif…
Far-infrared/millimetre emission in 3C sources. Dust in radio galaxies and quasars
Andreani, P.; Fosbury, R. A. E.; Freudling, W. +1 more
We present far-infrared and millimetric observations of a sample of 3C objects. Millimetre data were taken at 1.25 mm with the IRAM 30 m antenna feeding the MPIfR bolometer array. Mid-infrared (MIR) and far-infrared (FIR) photometry were carried out with the ISOCAM and ISOPHOT cameras on the ISO Satellite. Additional FIR IRAS observations are also…
Proper Motions in the Knotty, Bipolar Jet in Henize 2-90
Sahai, R.; Brandner, W.; Grebel, E. K. +4 more
Using second-epoch Hubble Space Telescope imaging of the unusual, bipolar jet source He 2-90, we have discovered proper motions of 0.03" yr-1 in the jet knots. Combining the proper motion with the knots' radial velocity measured from ground-based long-slit data, we find that the jet speed is roughly 150-360 km s-1, the source…
A Comparative Study of Jovian Cyclonic Features from a Six-Year (1994-2000) Survey
Colas, F.; Sánchez-Lavega, Agustín.; Lecacheux, J. +1 more
This work presents a six-year study aimed at characterizing the morphology and properties of the atmospheric features present in jovian cyclonic regions. It complements our previous analysis for the same period on the anticyclonic vortices (Morales-Juberias et al. 2002, Icarus 157, 76-90). The main difference between cyclonic and anticyclonic regi…
Submm/FIR CO line emission from the disk of the Class I protostar EL 29
Ceccarelli, C.; Caux, E.; Tielens, A. G. G. M. +3 more
We present observations towards the Class I protostar EL 29 of the CO J=6 -> 5 and J >= 15 transitions obtained with JCMT and ISO LWS respectively, and of five H_2 rotational lines obtained with ISO SWS. The simultaneous analysis of these observations reveals the presence of a warm gas component at about 170-250 K, ~ 550 AU in size, and whos…
Magellanic Clouds stellar clusters. II. New B,V CM diagrams for 6 LMC and 10 SMC clusters
Ripepi, V.; Castellani, V.; Brocato, E. +1 more
We present new CCD photometry for 6 LMC and 10 SMC stellar clusters taken at the ESO 1.54-m Danish Telescope in La Silla, to extend a previous investigation on Magellanic Clouds clusters based on HST snapshots. Thanks to the much larger area covered by the Danish detector, we investigate the spatial distribution of cluster stars, giving V, (B-V) C…