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Synchrotron emission is commonly found in relativistic jets from active galactic nuclei (AGNs) and microquasars, but so far its presence in jets from young stellar objects (YSOs) has not been proved. Here, we present evidence of polarized synchrotron emission arising from the jet of a YSO. The apparent magnetic field, with strength of ~0.2 milligauss, is(More)
A star like the Sun becomes a planetary nebula towards the end of its life, when the envelope ejected during the earlier giant phase becomes photoionized as the surface of the remnant star reaches a temperature of approximately 30,000 K. The spherical symmetry of the giant phase is lost in the transition to a planetary nebula, when non-spherical shells and(More)
4 RESUMEN Las observaciones interferométricas de la emisión maser de diversas moléculas (p. ABSTRACT Interferometric maser observations of several molecular species (e.g., H 2 O, OH, CH 3 OH) provide a very powerful tool to study with high-angular resolution the molecular gas close to protostars. In this way, groups of maser spots have been found to be(More)
We present radio continuum observations of the planetary nebula (PN) IRAS 17347-3139 (one of the only two known to harbour water maser emission), made to derive its spectral index and the turnover frequency of the emission. The spectrum of the source rises in the whole frequency range sampled, from 2.4 to 24.9 GHz, although the spectral index seems to(More)
We present 6 cm VLA observations of nine regions with molecular or HH outtows, that appear to be driven by young stellar objects of low bolometric luminosity. Radio continuum emission at 3.6 cm had been previously detected toward the center of symmetry of 13 outtows in these regions. With the new 6 cm observations we have been able to estimate the spectral(More)
We present [SII] images of the HH 30 and HL/XZ Tau region obtained at two epochs, as well as long-slit optical spectroscopy of the HH 30 jet. We measured proper motions of ∼100–300 km s −1 for the HH 30 jet and counterjet, and of ∼120 km s −1 for the HL Tau jet. Inclination angles with respect to the plane of the sky are 0 • –40 • for the HH 30 jet and 60 •(More)
The exact processes by which interstellar matter condenses to form young stars are of great interest, in part because they bear on the formation of planets like our own from the material that fails to become part of the star. Theoretical models suggest that ejection of gas during early phases of stellar evolution is a key mechanism for removing excess(More)
The current paradigm of star formation through accretion disks, and magnetohydrodynamically driven gas ejections, predicts the development of collimated outflows, rather than expansion without any preferential direction. We present radio continuum observations of the massive protostar W75N(B)-VLA 2, showing that it is a thermal, collimated ionized wind and(More)