A few Challenges in massive star evolution

ROTATION MAGNETIC FIELD MULTIPLICITY

How do these distributions vary with metallicity?

How do these distributions vary with the environment? (e.g. stellar density)

What is the origin of these distributions

What are the impacts on the interior?

40%vcrit

6-7%50-70%

+ Limongi & Chieffi 2013 13-120 Msol, solar ZNo internal magnetic field

+ Ekström et al. (2012)No internal magnetic field

+ Georgy et al. (2012; 2013)No internal magnetic field

Rotating models

With and withoutDynamo.

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:

Deheuvels et al. 2012

Asteroseismology of red giantsAsteroseismology of red giants

Ceillier et al. 2013

c = 710 ± 51 nHz (innermost 1.4% in r)

s < 150 ± 19 nHz

OBSERVATION MODELS

Vini= 2 km s-1

shellular

Solid Xc=0.1

Solid Xc=0

Nano Hertz Micro Hertz

ADDITIONAL MECHANISM OPERATING DURING THE HR CROSSING

Levesque et al. 2005

Upper luminosityOf SNIIP progenitors

Tracks from Ekström et al. 2012

RSG=End Point

RSG≠End Point

3) Where are the progenitors of the luminous type IIP SN ?

Smartt 2009

4) Which stars are the progenitors the type Ibc supenovae?

Jose Groh - The surprising look of massive stars before death

Jose Groh - The surprising look of massive stars before death

Jose Groh - The surprising look of massive stars before death Smartt 2009

4) Which stars are the progenitors the type Ibc supenovae?

Jose Groh - The surprising look of massive stars before death

Why so few detections of type Ibc progenitors? ~13 archives images, only one detection

Pre SN are WO stars not WN or WC starsToo low L for being detected

Groh et al, A&A in press; Yoon et al. 2012

Models

Observed upper limit

THE ONLY PROGENITOR DETECTED SO FAR FOR A TYPE Ibc: iPTF13bvn Cao et al. 2013

Models

Obs of iPTF13bvn

Groh et al. 2013 …QUITE WELL EXPLAINED BY THEORY OF SINGLE STARS

Jose Groh - The surprising look of massive stars before death

43-62

12-22

6-12

13-22

Observed rates Eldridge et al 2013Smith et al 2012

Rotating models with no internal magnetic field

Pre SN

For NS with P=20mms

For NS at break-upWoosley 2003

Zsol

WR

DO MASSIVE STARS ROTATE LIKE SOLID BODIES ON THE MS?

MAGNETIC FIELDS MAY ACTUALLY BE INVOLVED IN A DIFFERENT WAY

MAGNETIC BRAKING AT THE SURFACE

MAGNETIC BRAKING OF THE STELLAR CORES

LONG GRB MAY THEN OCCUR IN SITUATIONS WHERE THESE MAGNETIC BRAKING PROCESSES ARE NOT PRESENT

FAST ROTATORS AVOIDING THE RED SUPERGIANT PHASE?

HOW A RSG ROTATE IN THE INTERIOR? (SHELLULAR MODEL, NO MAGNETIC FIELD, SOLID BODY ROTATION IN CC)?

15 Msun, Z=0.014, Vini/Vcrit=0.4

A SMALL FAST SPINNING CORE IMMERGED IN A SLOWLY ROTATING ENVELOPE

TOTAL ANGULAR MOMENTUM:  (1050 cm2g-1) 12.0ANGULAR MOMENTUM IN THE ENVELOPE: 4.3ANGULAR MOMENTUM IN THE CORE:  1.0

Pulsar rotation estimated from conservation of angular momentum in the central 2 Msun: 

9.2e-5 s, a period 217 times smaller than 20 ms

Surface velocity is0.04 km s-1

critical velocityAt the surface isAbout 16 km s-1

If envelope absorb Lcore

increase of only 23% of the surface velocity

A COUPLING EFFICIENT ENOUGH BETWEEN THE CORE AND THE ENVELOPE WOULD HAVEA STRONG IMPACT ON THE ANGULAR MOMENTUM OF THE CORE WITHOUT CHANGING

TO MUCH THE ANGULAR MOMENTUM OF THE ENVELOPE

Mr/Msun

THE DIFFICULTYHOW TO RECONCILE THE LOSS OF LARGE AMOUNT OF MASS (H-RICH ENVELOPE REMOVED)

WITH FAST ROTATING CORE?

POSSIBLE SOLUTIONSSTARS BECOME H-POOR BY EVOLVING HOMOGENEOUSLY

THE ANGULAR MOMENTUM TRANSPORT BETWEEN CORE AND ENVELOPEREMAINS MODEST AT EVERY TIME

PREDICTIONS AND IMPLICATIONS ARE DIFFERENTHOMOGENEOUS EVOLUTION DIFFERENTIAL ROTATION

Only very fast rotators at low Z

GRB/CC ~ 2% at Z=0.002, 5% at Z=0.00001

Moderate rotators and Ic only when (C+O >He)

GRB/CC ~ 7% at Z=0.004, 0.008

Moderately rotating stars are also solid body rotating on MS Rotation of pulsars

Yoon et al. 2006 (interior magnetic field)

(No interior magnetic fields)

Asteroseismology?

need braking mechanisms to explain rotation of pulsars

Hirschi et al. 2005; Georgy et al. 2009, 2012

Core braking mechanism?

WEAK WR WINDS AT LOW Z NEEDED

Roche approximation

Shellularrotation

MOST OF MASS

SPHERICALDISTRIBUTION

MOST OF MASS

SPHERICALDISTRIBUTION

EQUATIONS FOR MEAN VALUES ON ISOBARS

ON ISOBARS DIFFERENCE WITH RESPECT TO MEAN VALUES SMALL (LEGENDRE)

1.5D

Numerical treatment of the meridional circulation

Treatment of the ``mixing blocking effect’’ of mu-gradients

Choice of the diffusion coefficient

Inclusion of a dynamo in radiative zone

Inclusion of internal waves

Inclusion of anisotropic winds

Inclusion of magnetic braking by the winds

Jose Groh - The surprising look of massive stars before death

Jose Groh - The surprising look of massive stars before death

Jose Groh - The surprising look of massive stars before death

Jose Groh - The surprising look of massive stars before death (after evol. tracks from Meynet & Maeder 03, Ekstrom+ 12)

OB-type LBV WR SN Ibc or BH

Massive star evolution (at solar Z, above 30 Massive star evolution (at solar Z, above 30 M )M )

OB-type

85M ☉

LBVWolf-Rayet

☉

So far, no observations of WRs as SN progenitors (Smartt 09)

5) ROTATION AND PROGENITORS OF LONG

SOFTGAMMA RAY BURSTS

Jose Groh - The surprising look of massive stars before death

Jose Groh - The surprising look of massive stars before death

Jose Groh - The surprising look of massive stars before death

Jose Groh - The surprising look of massive stars before death