The binary and the disk: the beauty is found within NGC3132 with JWST by Raghvendra Sahai et al. on Wednesday 30 November

The planetary nebula (PN) NGC3132 is a striking example of the dramatic but

poorly understood, mass-loss phenomena that (1-8) Msun stars undergo during

their death throes as they evolve into white dwarfs (WDs). From an analysis of

JWST multiwavelength (0.9-18 micron) imaging of NGC3132, we report the

discovery of an extended dust cloud around the WD central star (CS) of NGC3132,

seen most prominently in the 18 micron~image, with a surface-brightness limited

radial extent of >~2 arcsec. We show that the A2V star located 1.7 arcsec to

CS's North-East (and 0.75 kpc from Earth) is gravitationally-bound to the

latter, by the detection of relative orbital angular motion of (0.24+/-0.045)

deg between these stars over ~20 yr. Using aperture photometry of the CS

extracted from the JWST images, together with published optical photometry and

an archival UV spectrum, we have constructed the spectral-energy distribution

(SED) of the CS and its extended emission over the UV to mid-IR (0.091-18

micron) range. We find that fitting the SED of the CS and the radial intensity

distributions at 7.7, 12.8 and 18 micron with thermal emission from dust

requires a cloud that extends to a radius of >~1785 au, with a dust mass of

~1.3 x 10^(-2) M(Earth) and grains that are 70% silicate and 30% amorphous

carbon. We propose plausible origins of the dust cloud and an evolutionary

scenario in which a system of three stars -- the CS, a close low-mass

companion, and a more distant A2V star -- forms a stable hierarchical triple

system on the main-sequence but becomes dynamically unstable later, resulting

in the spectacular mass-ejections that form the current, multipolar PN.

arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.16741v1