Massive Stars Mass Loss Mathieu Renzo Advisors: S. N. Shore, C. D. - - PowerPoint PPT Presentation

PhD Recruitment, February 12, API/GRAPPA

Massive Stars Mass Loss

Mathieu Renzo Advisors: S. N. Shore, C. D. Ott

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Mass Loss - Why is it important ... ... for the environment of the stars?

• Chemical and dynamical evolution of Galaxies
• Effects on star formation
• Giant bubbles

... for the stellar structure?

• Evolutionary timescale
• Final fate (BH, NS or WD?)
• Light curve (LC) and explosion spectrum
• Appearence: CSM and wind features (WR)
• Role in the solution of the RSG problem?

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Mass Loss - Possible Driving Mechanisms Metal Line Driving

⇐

Winds Dynamical Instabilities

⇐

LBVs, Episodic Mass Loss, Super-Eddington Winds Binary interactions

⇐

Roche Lobe Overflows (RLO)

Figure: η Car, false colors.

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Mass Loss in Stellar Evolution Codes ( )

Figure: From Smith 2014, ARA&A, 52, 487S

Parametric models with large uncertainties (clumpiness, non-wind mass loss) encapsulated in efficiency factor: ˙ M(L, Teff, Z, R, M, ...)

←

η ˙ M(L, Teff, Z, R, M, ...)

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Mass Loss - Different ˙ M prescriptions with Grid of Z⊙ stellar models (Renzo et al., in preparation):

• Initial mass:

MZAMS = {15, 20, 25, 30} M⊙;

• Efficiency:

η = {1,

1 3, 1 10} ;

• Different combinations of wind mass loss rates

for “hot”, “cool” and WR stars: Kudritzki et al. ’89; Vink et al. ’00, ’01; Van Loon et al. ’05; Nieuwenhuijzen et al. ’90; De Jager et al. ’88; Nugis & Lamers ’00; Hamann et al. ’98.

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Mass Loss - Preliminary Results with Example: MZAMS = 15M⊙, Z⊙ evolutionary tracks

3.4 3.6 3.8 4.0 4.2 4.4 4.6 log(Teff/[K]) 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 5.0 5.1 5.2 log(L/L⊙) Kudritzki et al., de Jager et al. η = 1.0 η = 0.33 η = 0.1 3.4 3.6 3.8 4.0 4.2 4.4 4.6 log(Teff/[K]) 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 5.0 5.1 5.2 log(L/L⊙) Vink et al., de Jager et al. η = 1.0 η = 0.33 η = 0.1

⇒ Early (“hot”) wind influences subsequent evolution

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Experiment with Episodic Mass Loss (e.g. RLO)

• ∆Mwind ≪ ∆Mepisodic (?)
• Could explain H-poor progenitors of SNIIb/Ib/Ic

and/or CSM for SNIIn

• Dynamics ⇒

not ready

3.5 3.6 3.7 3.8 3.9 4.0 4.1 4.2 4.3 4.4 4.5 log10(Teff/[K]) 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 5.0 5.1 5.2 5.3 5.4 log10(L/L⊙) Stripping MZAMS = 15M⊙, Z⊙ unstripped stripped 1M⊙ stripped 2M⊙ stripped 3M⊙ stripped 4M⊙ stripped 5M⊙ stripped 6M⊙ stripped 7M⊙

Experiment with Episodic Mass Loss (e.g. RLO)

• ∆Mwind ≪ ∆Mepisodic (?)
• Could explain H-poor progenitors of SNIIb/Ib/Ic

and/or CSM for SNIIn

• Dynamics ⇒

not ready

3.5 3.6 3.7 3.8 3.9 4.0 4.1 4.2 4.3 4.4 4.5 log10(Teff/[K]) 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 5.0 5.1 5.2 5.3 5.4 log10(L/L⊙) Stripping MZAMS = 15M⊙, Z⊙ unstripped stripped 1M⊙ stripped 2M⊙ stripped 3M⊙ stripped 4M⊙ stripped 5M⊙ stripped 6M⊙ stripped 7M⊙

⇒ LC (SNEC)

(Morozova et al., in preparation)

Always Global Hydrostatic Equilibrium

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Light Curve from the Stripped Models with SNEC

50 100 150 41 42 43 44

Time since breakout (days) log10 L [10x erg/s]

M0 M1 M2 M3 M4 M5 M6 M7 M8

Figure: From Morozova et al., in preparation

Dashed: Eej = 1051 ergs, Plain: Eej = 2 × 1051 ergs

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Mass Loss - Conclusions Improvement needed for the dynamical instabilities

• Mass loss is important both for the stellar

structures and their environment;

• Several mass loss mechanisms, many neglected

in stellar evolution codes;

• Large theoretical and observational

uncertainties on the mass loss rate ˙ M;

• Effects of these uncertainties unexplored in a

systematic way. Thank you for your attention.

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Challenges: near-to-super-Eddington envelopes

dPgas dr = dPrad dr LEdd Lrad − 1

• ,

5.0 5.5 6.0 6.5 7.0 log10(T/[K]) 0.5 1.0 1.5 2.0 2.5 κ [cm2 g−1] OPAL: X = 0.7, log(ρ/T63) = −5 Z=0.02 Z=0.01 Z=0.004 Z=0.001 Z=0.0001

MZAMS 20M⊙ ⇒ insufficient F MLT

conv

MLT++:

∇T − ∇ad → α∇f∇(∇T − ∇ad)

α∇ ≡ α∇(β, ΓEdd), f∇ ≪ 1

• r/R⊙

log (ρ)

70 M⊙, Teff = 5000 K

a)

−10.1 −10.0 −9.9 log

• P

gas

• b)

2.31 2.38 log (P)

c)

2.7 3.0 3.3 S/ (N

AkB) d)

1000 1100 1200 1300 60 80

Figure: From Paxton et al. 2013, ApJS, 208, 5p

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Episodic Mass Loss: Choice of Stripping Moment

3.4 3.5 3.6 3.7 3.8 3.9 4.0 4.1 4.2 4.3 4.4 4.5 log10(Teff/[K]) 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 5.0 5.1 5.2 log10(L/L⊙) Middle SGB

R = 375R⊙ ≡ max(R)

2

Convective Envelope Maximum Extension M = 15M⊙, Z = Z⊙ unstripped

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Wind Mass Loss: Preliminary M(t) spread

The evolution is stopped at oxygen depletion Xc(16O) ≤ 0.4.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 t [Myr] 6 7 8 9 10 11 12 13 14 15 M [M⊙]

Vink et al., de Jager et al. Kudritzki et al., Nieuwenhuijzen et al. Kudritzki et al., de Jager et al. Vink et al., Nieuwenhuijzen et al. Kudritzki et al., van Loon et al. Vink et al., van Loon et al. η = 1.0 η = 0.33 η = 0.1

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