Angular momentum transport chemical mixing and nucleosynthesis Georges

ROTATION Howarth et al. 97, Dufton et al. 2006, Hunter et al. 2009, Zorec

Rotating models With and without Dynamo. + Limongi & Chieffi 2013, 2018 13 -120

ROTATION CAN INDUCE MIXING MASS LOSS • Stellar winds • Anisotropic losses of mass

PROCESSES AFFECTING THE ANGULAR MOMENTUM CONTENT OF MASSIVE STARS TOTAL ANGULAR MOMENTUM DISTRIBUTION Single

WITHOUT INTERNAL MAGNETIC FIELD Zahn 1992 WITH INTERNAL MAGNETIC FIELD Spruit 1999, 2002 But

15 Msol, Z=0. 020, Vini=300 km s-1 Maeder & Meynet 2005 MAGNETIC FIELDS SOLID

120 Msun 85 Msun 60 Msun 40 Msun 32 Msun Mini [Msun] Vini km

HOW TO CONSTRAIN THIS TRANSPORT? - EVOLUTION OF THE SURFACE ROTATION-SURFACE ABUNDANCES - HELIOSEISMOLOGY

Asteroseismology of red giants Mixed modes in the red giant KIC 7341231 (0. 84

A PARAMETRIC APPROACH TO PROBE SOME PROPERTIES OF THE MISSING PROCESS Eggenberger et al.

Efficiency of the transport should decrease with evolution during the subgiant phase Increases with

Angular momentum in the remnant No internal magnetic field Internal magnetic field

CONCLUSIONS Present rotating stellar models miss an angular momentum Transport process In low mass

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Angular momentum transport, chemical mixing and nucleosynthesis Georges Meynet Geneva Observatory, Geneva University Why do we care on the effects of rotation? How can we test the angular momentum transport processes? Different physics with different outputs A new grid for s-process from rotating massive stars

ROTATION Howarth et al. 97, Dufton et al. 2006, Hunter et al. 2009, Zorec and Royer 2012

Rotating models With and without Dynamo. + Limongi & Chieffi 2013, 2018 13 -120 Msol, solar Z and lower No internal magnetic field + Groh et al. Submitted 1/35 solar Z, No internal magnetic field + Ekström et al. (2012) No internal magnetic field + Georgy et al. (2012; 2013) No internal magnetic field +Szécsi et al. (2015) Köhler et al. (2015)

ROTATION CAN INDUCE MIXING MASS LOSS • Stellar winds • Anisotropic losses of mass and J MIXING • Meridional circulation • Shear instabilities • Turbulence • Transport of angular momentum of elements Donati et al. 2006 MAGNETIC FIELD • Dynamo • Internal coupling • Effects on element transport • Wind magnetic braking Effects in Asteroseismology STRUCTURE • Oblateness (interior, surface) • Differential rotation

PROCESSES AFFECTING THE ANGULAR MOMENTUM CONTENT OF MASSIVE STARS TOTAL ANGULAR MOMENTUM DISTRIBUTION Single and close binary stars - INTERNAL ANGULAR MOMENTUM TRANSPORT (internal magnetic field) - MASS LOSSES BY LINE DRIVEN WINDS (surface magnetic field) - MECHANICAL MASS LOSSES Close binary stars - TIDAL INTERACTIONS - MASS TRANSFER IN CLOSE BINARIES - COMMON ENVELOPE PHASE - MERGING Not a collection of additive processes, rather processes whose interaction should ideally be accounted for

PROCESSES AFFECTING THE ANGULAR MOMENTUM CONTENT OF MASSIVE STARS TOTAL ANGULAR MOMENTUM DISTRIBUTION Single and close binary stars - INTERNAL ANGULAR MOMENTUM TRANSPORT TWO FLAVOURS OF ROTATING MODELS

TWO FLAVOURS OF ROTATING MODELS

WITHOUT INTERNAL MAGNETIC FIELD Zahn 1992 WITH INTERNAL MAGNETIC FIELD Spruit 1999, 2002 But Zahn et al. 2007 Differential rotation Solid body rotation Mixing of the elements due to shear Mixing of the elements due to meridional circulation Efficiency of mixing ÷ dΩ/dr Efficiency of mixing ÷ Ω CONSEQUENCES FOR THE EVOLUTION OF THE ANGULAR MOMENTUM

TWO FAMILIES WITH DIFFERENT OUTPUTS

15 Msol, Z=0. 020, Vini=300 km s-1 Maeder & Meynet 2005 MAGNETIC FIELDS SOLID BODY ROTATION

15 Msol Z=0. 020 Maeder & Meynet 2005

Szecsi et al. 2015

120 Msun 85 Msun 60 Msun 40 Msun 32 Msun Mini [Msun] Vini km s-1 150 350 77 350 39 350 Mini [Msun] Vini km s-1 120 463 85 469 60 435 40 393 32 366 25 343 20 314 25 Msun 20 Msun 15 Msun Groh et al submitted

WHICH MODEL IS PREFERRED BY NATURE?

HOW TO CONSTRAIN THIS TRANSPORT? - EVOLUTION OF THE SURFACE ROTATION-SURFACE ABUNDANCES - HELIOSEISMOLOGY & ASTEROSEISMOLOGY - YOUNG PULSAR ROTATION RATES-WHITE DWARF SPIN - SPIN OF MERGING BLACK HOLES - SPIN OF BH IN XRB

Asteroseismology of red giants Mixed modes in the red giant KIC 7341231 (0. 84 Msol, [Fe/H]=-1) - Rotational splittings for 18 modes (Deheuvels et al. 2012) Inversion of the rotation profile: OBSERVATION MODELS Micro Hertz Nano Hertz c = 710 ± 51 n. Hz (innermost 1. 4% in r) Vini= 2 km s-1 shellular Solid Xc=0. 1 s < 150 ± 19 n. Hz Deheuvels et al. 2012 Solid Xc=0 Ceillier et al. 2013

Asteroseismology of red giants Mixed modes in the red giant KIC 7341231 (0. 84 Msol, [Fe/H]=-1) - Rotational splittings for 18 modes (Deheuvels et al. 2012) Inversion of the rotation profile: OBSERVATION MODELS Micro Hertz Nano Hertz c = 710 ± 51 n. Hz (innermost 1. 4% in r) Vini= 2 km s-1 ADDITIONAL MECHANISM OPERATING DURING THE HR shellular CROSSING Solid Xc=0. 1 s < 150 ± 19 n. Hz Deheuvels et al. 2012 Solid Xc=0 Ceillier et al. 2013

A PARAMETRIC APPROACH TO PROBE SOME PROPERTIES OF THE MISSING PROCESS Eggenberger et al. 2018, in press

Efficiency of the transport should decrease with evolution during the subgiant phase Increases with evolution during the red giant phase. In both case, increase of the differential rotation above the Core a different mechanism is at work? Eggenberger + 2018

ANY CONSTRAINTS FOR MASSIVE STARS?

Angular momentum in the remnant No internal magnetic field Internal magnetic field

CONCLUSIONS Present rotating stellar models miss an angular momentum Transport process In low mass stars, during the evolution in the subgiant phase, this process decreases in importance. In low mass stars, during the evolution in the red giant phase, this process increases in importance. Are such processes also active in massive stars? ew grids at Z=0. 001 for s-process yields from (non-magnetuc) tating stellar models (same family of models as Frischknecht et a