000008029 001__ 8029
000008029 005__ 20260226100609.0
000008029 0247_ $$2DOI$$a10.3847/1538-4357/adc91c
000008029 037__ $$aSCART-2026-0126
000008029 100__ $$aSahai, Raghvendra   
000008029 245__ $$aJWST Observations of the Ring Nebula (NGC 6720). III. A Dusty Disk around Its Central Star
000008029 260__ $$c2025
000008029 520__ $$aThe planetary nebula NGC 6720, also known as the "Ring Nebula," is one of the most iconic examples of nearby planetary nebulae whose morphologies present a challenge to our theoretical understanding of the processes that govern the deaths of most stars in the Universe that evolve on a Hubble time. We present new imaging with JWST of the central star of this planetary nebula (CSPN) and its close vicinity, in the near-to-mid-IR wavelength range. We find the presence of a dust cloud around the CSPN, both from the spectral energy distribution at wavelengths ≳5 μm as well as from radially extended emission in the 7.7, 10, and 11.3 μm images. From the modeling of these data, we infer that the CSPN has a luminosity of 310 L⊙ and is surrounded by a dust cloud with a size of ∼2600 au, consisting of relatively small amorphous silicate dust grains (radius ∼0.01 μm) with a total mass of 1.9 × 10‑6 M⊕. However, our best-fit model shows a significant lack of extended emission at 7.7 μm—we show that such emission can arise from a smaller (7.3 × 10‑7 M⊕) but uncertain mass of (stochastically heated) ionized polycyclic aromatic hydrocarbon (PAHs). However, the same energetic radiation also rapidly destroys PAH molecules, suggesting that these are most likely being continuously replenished, via the outgassing of cometary bodies and/or the collisional grinding of planetesimals. We also find significant photometric variability of the central source that could be due to the presence of a close dwarf companion of mass ≤0.1 M⊙.
000008029 594__ $$aNO
000008029 6531_ $$aPlanetary nebulae
000008029 6531_ $$aStellar mass loss
000008029 6531_ $$aPost-asymptotic giant branch 
000008029 6531_ $$aCircumstellar dust
000008029 6531_ $$aJames Webb Space Telescope
000008029 6531_ $$aSilicate grains
000008029 6531_ $$aPolycyclic aromatic hydrocarbons
000008029 6531_ $$a Infrared astronomy
000008029 6531_ $$aPlanetesimals
000008029 6531_ $$aUltraviolet spectroscopy
000008029 6531_ $$aGaia
000008029 6531_ $$aLight curves
000008029 6531_ $$aSolar and Stellar Astrophysics
000008029 700__ $$aVan de Steene, Griet 
000008029 700__ $$avan Hoof, Peter A. M.  
000008029 700__ $$aZijlstra, Albert  
000008029 700__ $$aVolk, Kevin  
000008029 700__ $$aDinerstein, Harriet L. 
000008029 700__ $$aBarlow, Michael J.  
000008029 700__ $$aPeeters, Els  
000008029 700__ $$a Manchado, Arturo 
000008029 700__ $$a Matsuura, Mikako  
000008029 700__ $$aCami, Jan  
000008029 700__ $$aCox, Nick L. J.  
000008029 700__ $$aAleman, Isabel  
000008029 700__ $$aBernard-Salas, Jeronimo 
000008029 700__ $$aClark, Nicholas 
000008029 700__ $$aJusttanont, Kay  
000008029 700__ $$aKaplan, Kyle F. 
000008029 700__ $$aKavanagh, Patrick J.  
000008029 700__ $$a Wesson, Roger 
000008029 773__ $$c1-17$$n1$$pThe Astrophysical Journal$$v985$$y2025
000008029 8560_ $$fgriet.vandesteene@ksb-orb.be
000008029 85642 $$ahttps://ui.adsabs.harvard.edu/abs/2025ApJ...985..101S/abstract
000008029 905__ $$apublished in
000008029 980__ $$aREFERD