When stars collide: of planetary nebulae, jets and cosmic outbursts Orsola De Marco Macquarie University Add photos of the people I am reviewing? Collaborators: Jan Staff (Florida State) Jean-Claude Passy (Bonn U) Roberto Iaconi (Macquarie U) Todd Hillwig (Valparaiso U) Falk Herwig (U Victoria) Thomas Reichardt (Macquarie U)

Stellar evolution for 1-8Mo stars CRL 2688 Post-AGB star + pre PN NGC 6543 pre WD star + ionised PN ~0.15 pc AFGL 3068 Post AGB phase ~0.15 pc AGB phase ~0.15 pc WD cooling track

<~20% spherical ~20% bipolar ~60% ellipticals Parker et al. 2006

We thought we had the solution to the formation of non-spherical PN …

Only <20% of the PN progenitor stellar population has companions that will interact on the AGB. But 80% of nebulae are non-spherical!

20% of 1-8Mo stars can have a binary interaction on the AGB … expect 20% of PN to be non-spherical If some single and non-interacting binary stars do not make a PN… … the fraction of non-spherical PN can increase Moe and De Marco, 2006, 2012

What can we say from observations 15-20% of all central stars of PN are short-period binaries (Bond 2000; Miszalski et al. 2009) There are likely more … Artist: Dana Berry

The Kepler sample: 5 PN Merger No variability Likely binary Binary De Marco et al. 2015 NGC 6826 (V ~ 11) Bruce Balick Abell 61 (V ~ 17) Jim Shuder Merger No variability Likely binary Binary Binary Pa 5 (V ~ 16) Kn 61 (V ~ 18) Travis Rector J19411+4324 (V ~ 14) Aller et al 2013

What can we say from observations 15-20% of all central stars of PN are short-period binaries (Bond 2000; Miszalski et al. 2009) There are likely more … These are post-common envelope binaries De Marco et al. 2008, Hillwig et al. 2010,2014 Current scenarios predict only 5% (Madappatt, De Marco, Villaver 2016) Artist: Dana Berry

Shaping PN with common envelope interactions Common envelope interactions promote equatorially-enhanced mass loss, magnetic fields and jets Passy et al. 2012

Shaping PN with common envelope interactions Jet masses and kinematics in post-common envelope PN allow us to determine the strength of the magnetic fields in common envelope interactions (Tocknell, De Marco & Wardle 2014)

A jet shaping model for OH231.8+4.2 Nebula around a 3.05Mo Mira (AGB star) Well measured lobes momenta, energies and power Kinematics give a lobe age of 800 years Any other values of the momentum?

A jet shaping model 3D hydrodynamic model with an eccentric binary interaction + Roche lobe overflow, disk formation and common envelope merger Characterization of disk mass and survival time scales Analytical determination of jet Speeds and momenta/energies/ power Staff et al. 2016a Any other values of the momentum?

Further implications of jet models e Carinae: luminous blue variable, massive binary 150Mo + 30 Mo, 5.5 year period, 0.9 eccentricity

Connecting outflows and outbursts NGC6826 (PN): Common envelope merger outburst ~10,000 years ago, resolved outflow V838 Mon: Common envelope merger of a ~6Mo sub-giant star with companion, outburst 2002, no outflow yet V1309Sco: Common envelope merger of a 1.5Mo and 0.15Mo, outburst 2010, no resolved outflow yet

LSST will find many mergers and binary-induced outbursts

Prediction of BH merger rates rest on shaky common envelope Physics