Using kinematic properties of pre-planetary nebulae to constrain engine paradigms

摘要: Some combination of binary interactions and accretion plausibly conspire to produce the ubiquitous collimated outflows from planetary nebulae (PN) their presumed pre-PN (PPN) precursors. But which engines are viable? The difficulty in observationally resolving warrants pursuit indirect constraints. We show how kinematic outflow data for 19 PPN can be used determine minimum required rates. consider mainsequence (MS) white dwarf (WD) accretors five example rates inferred published models compare with minima derived momentum conservation. While our primary goal is method anticipation more better theoretical constraints, taking present results at face value already rules out modes accretion: Bondi– Hoyle–Lyttleton (BHL) wind Roche lobe overflow (M-WRLOF, based on Mira parameters) too feeble all 19/19 objects an MS accretor. For a WD accretor, BHL ruled 18/19 M-WRLOF 15/19 objects. RLOF Red Rectangle level accommodate 7/19 objects, though higher not yet out. Accretion operating within common envelope evolution if jet collimation maintained. Overall, subEddington accretor acceptable but 8/19 would require super-Eddington WD.