Spatio-kinematic modelling of Abell 65, a double-shelled planetary nebula with a binary central star

摘要

We present the first detailed spatio-kinematical analysis and modelling ofthe planetary nebula Abell 65, which is known to host a post-common envelope,binary, central star system. As such, this object is of great interest instudying the link between nebular morphology and central star binarity. [OIII]5007A and H-alpha+[NII]6584A longslit spectra and imagery of Abell 65were obtained with the Manchester Echelle Spectrometer on the 2.1-m telescopeat the San Pedro Martir Observatory (MES-SPM). Further [OIII]5007A longslitspectra were obtained with the Ultraviolet and Visual Echelle Spectrograph onthe Very Large Telescope (VLT-UVES). These data were used to develop aspatio-kinematical model for the [OIII]5007A emission from Abell 65. A"best-fit" model was found by comparing synthetic spectra and images renderedfrom the model to the data. The model comprises an outer shell and an innershell, with kinematical ages of 15000 +/- 5000 yr kpc^-1 and 8000 +/- 3000 yrkpc^-1, respectively. Both shells have peanut-shaped bipolar structures withsymmetry axes at inclinations of 55 +/- 10 deg (to the line-of-sight) for theouter shell and 68 +/- 10 deg for the inner shell. The near-alignment betweenthe nebular shells and the binary orbital inclination (of 68 +/- 2 deg) isstrongly indicative that the binary is responsible for shaping the nebula.Abell 65 is one of a growing number of planetary nebulae (seven to date,including Abell 65 itself) for which observations and modelling support theshaping influence of a central binary.