We have mapped the CO(3-2) line emission around the Mira AB system at 0.5 resolution using the Atacama Large Millimeter/submillimeter Array (ALMA). The CO map shows amazing complexity. The circumstellar gas has been shaped by different dynamical actors during the evolution of the system and several morphological components can be identified. The companion is marginally resolved in continuum emission and is currently at 0.487±0.006 separation. In the main line component, centered on the stellar velocity, spiral arcs around Mira A are found. The spiral appears to be relatively flat and oriented in the orbital plane. An accretion wake behind the companion is clearly visible and the projected arc separation is of order 5''. In the blue wing of the line emission, offset from the main line, several large (∼5-10''), opposing arcs are found. We tentatively suggest that this structure is created by the wind of Mira B blowing a bubble in the expanding envelope of Mira A.
@article{arxiv.1410.1529,
title = {The wonderful complexity of the Mira AB system},
author = {S. Ramstedt and S. Mohamed and W. H. T. Vlemmings and M. Maercker and R. Montez and A. Baudry and E. De Beck and M. Lindqvist and H. Olofsson and E. M. L. Humphreys and A. Jorissen and F. Kerschbaum and A. Mayer and M. Wittkowski and N. L. J. Cox and E. Lagadec and M. L. Leal-Ferreira and C. Paladini and A. Pérez-Sánchez and S. Sacuto},
journal= {arXiv preprint arXiv:1410.1529},
year = {2014}
}