ALMA high-frequency long baseline campaign in 2021: highest angular resolution submillimeter wave images for the carbon-rich Star R Lep

Instrumentatio

ALMA high-frequency long baseline campaign in 2017: Band-to-band phase referencing in submillimeter waves

Instrumentatio

Supernova Interaction with a Circumstellar Medium

The explosion of a core collapse supernova drives a powerful shock front into the wind from the progenitor star. A layer of shocked circumstellar gas and ejecta develops that is subject to hydrodynamic instabilities. The hot gas can be observed directly by its X-ray emission, some of which is absorbed and re-radiated at lower frequencies by the ejecta and the circumstellar gas. Synchrotron radiation from relativistic electrons accelerated at the shock fronts provides information on the mass loss density if free-free absorption dominates at early times or the size of the emitting region if synchrotron self-absorption dominates. Analysis of the interaction leads to information on the density and structure of the ejecta and the circumstellar medium, and the abundances in these media. The emphasis here is on the physical processes related to the interaction.Comment: 22 pages, 7 figures, to appear as a Chapter in "Supernovae and Gamma-Ray Bursts," edited by K. W. Weiler (Springer-Verlag

The 2014 ALMA Long Baseline Campaign: First Results from High Angular Resolution Observations toward the HL Tau Region

Interstellar matter and star formatio

The 2014 ALMA Long Baseline Campaign: An Overview

Instrumentatio

Is the Outflow from RT Vir Bipolar or Rotating

Original paper can be found at: http://www.astrosociety.org/pubs/cs/195-221.html--Copyright Astronomical Society of the PacificWe present high angular resolution observations of H2O maser proper motions in the circumstellar envelope of the semi-regular variable RT Vir. The MERLIN observations, at 12-mas angular resolution, were used to map H2O maser emission at ~2 week intervals over 10 weeks in 1996, during which period the brightness distribution changed markedly

The Magnetic Field and Maser Structure in the Proto-Planetary Nebula IRAS 20406+2953

Original paper can be found at: http://www.astrosociety.org/pubs/cs/309.html--Copyright Astronomical Society of the PacificOur understanding of the morphological evolutionary path from AGB star to planetary nebula is still unclear; broadly speaking, we are faced with shaping models that primarily detail varying forms of binary evolution, and those which concentrate on the in uence of stellar magnetic fields. Here we report the detection and measurement of a magnetic field in the proto-planetary nebula IRAS 20406+2953. This is the second such object in which we have measured a field strength and shown that the magnetic energy density in the wind is an order of magnitude higher than the bulk mechanical energy density, suggesting that the magnetic field could be in uential in shaping the out ow