The morpho-kinematics of the circumstellar envelope around the AGB star EP Aqr

摘要: ALMA observations of CO(1-0) and CO(2-1) emissions the circumstellar envelope EP Aqr, an oxygen-rich AGB star, are reported. A thorough analysis their properties is presented using original method based on separation data-cube into a low velocity component associated with equatorial outflow faster bipolar outflow. number important new results obtained concerning distribution in space effective emissivity, temperature, density flux matter. mass loss rate (1.6$\pm$0.4)10$^{-7}$ solar masses per year measured. The main parameters defining morphology kinematics evaluated uncertainties inherent to de-projection critically discussed. Detailed region including measurement line width precise description observed inhomogeneity both kinematics. In particular, addition presence previously spiral enhancement at very small Doppler velocities, similarly significant but uncorrelated circular expansion revealed, close limit sensitivity. place constraints models proposing descriptions mechanism, cannot choose among them confidence.