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Observations of 12CO(3-2) emission of the circumbinary envelope of Mira Ceti, made by ALMA are analysed. The observed Doppler velocity distribution is made of three components: a blue-shifted south-eastern arc, which can be described as a ring in slow radial expansion, ~1.7 km/s, making an angle of ~50 deg with the plane of the sky and born some 2000 years ago; a few arcs, probably born at the same epoch as the blue-shifted arc, all sharing Doppler velocities red-shifted by approximately 3 +/- 2 km/s with respect to the main star; the third, central region dominated by the circumbinary envelope, displaying two outflows in the south-western and north-eastern hemispheres. At short distances from the star, up to ~1.5, these hemispheres display very different morphologies: the south-western outflow covers a broad solid angle, expands radially at a rate between 5 and 10 km/s and is slightly red shifted; the north-eastern outflow consists of two arms, both blue-shifted, bracketing a broad dark region where emission is suppressed. At distances between ~1.5 and ~2.5 the asymmetry between the two hemispheres is significantly smaller and detached arcs, particularly spectacular in the north-eastern hemisphere are present. Close to the stars, we observe a mass of gas surrounding Mira B, with a size of a few tens of AU, and having Doppler velocities with respect to Mira B reaching +/-1.5 km/s, which we interpret as gas flowing from Mira A toward Mira B.
We analyse ALMA observations of the 12CO(3-2) emission of the circumstellar envelope (CSE) of the Mira variable binary star W Aql. These provide, for the first time, spatially resolved Doppler velocity spectra of the CSE up to angular distances to th
We study the morpho-kinematics of the circumbinary envelope of Mira Ceti between $sim$100 and $sim$350 au from the stars using ALMA observations of the SiO ($ u$=0, $J$=5-4) and CO ($ u$=0, $J$=3-2) emissions with the aim of presenting an accurate an
Observations of the $^{12}$CO(3-2) emission of the circumstellar envelope (CSE) of the variable star $pi^1$ Gru using the compact array (ACA) of the ALMA observatory have been recently made accessible to the public. An analysis of the morphology and
Using ALMA observations of the C$^{18}$O(2-1) line emission of the gas envelope of protostar L1527, we have reconstructed its morphology and kinematics under the assumption of axisymmetry about the west-east axis. The main original contribution to ou
The prototypical Mira variable, $o$ Cet (Mira), has been observed as a Science Verification target in the 2014 ALMA Long Baseline Campaign with a longest baseline of 15 km. ALMA clearly resolves the images of the continuum and molecular line emission