Hydrodynamical Interpretation of Basic Nebular Structures M. Steffen & D. Schönberner M. Steffen & D. Schönberner Abell 39 (WIYN )

Hydrodynamical Interpretation Hydrodynamical Interpretation of Basic Nebular Structuresof Basic Nebular Structures

M. Steffen &M. Steffen &

D. D. SchönbernerSchönberner

M. Steffen &M. Steffen &

D. D. SchönbernerSchönberner

Abell 39 (WIYN)

Astrophysikalisches Institut Astrophysikalisches Institut Potsdam, GermanyPotsdam, Germany

Hydrodynamical Interpretation Hydrodynamical Interpretation of Basic Nebular Structuresof Basic Nebular Structures

Introduction: observed structures

PN physics and hydrodynamical modeling

Results from state-of-the-art simulations typical time evolution of PN structures dependence on mass loss of AGB progenitor

Conclusions and outlook

M. Steffen & D. SchönbernerM. Steffen & D. SchönbernerAstrophysikalisches Institut Potsdam, GermanyAstrophysikalisches Institut Potsdam, Germany

Observed PN structures: An overview

Examples of Examples of young young Planetary Nebulae Planetary Nebulae

Teff 36 000 K

He 2-131

Teff 30 000 K

IC 418

Sharp ionization front, optically thick in Ly-continuum

HST H Image HST H Image

Examples of Examples of middle-aged middle-aged Planetary Nebulae Planetary Nebulae

Teff 50 000 K

NGC 6826

Teff 50 000 K

IC 3568

Typical double-shell PNe, optically thin in Ly-continuum

HST color composite

HST V image

Rim RimShell

Shell

Halo

NGC 6826, observed with PMAS A&G camera (© 2004, M. Roth)

OIII, shortOIII, short

AGB HaloAGB Halo

OIII, long

Example of an AGB halo: Example of an AGB halo: NGC 6826NGC 6826

Examples of Examples of middle-agedmiddle-aged Planetary Nebulae Planetary Nebulae

Teff 100 000 K

NGC 2022NGC 2022

Teff 75 000 K

NGC 3242NGC 3242

Typical double-shell PNe, optically thin in Ly-continuum

HST V imageHST V imageHST V imageHST V image

Rim

RimShell

Shell

Halo

Xrays

NGC 2022 [OIII] images obtained with NTT/EMMI (Corradi et al. 2003)

Example of an AGB halo: Example of an AGB halo: NGC 2022NGC 2022

Examples of Examples of old old Planetary Nebulae Planetary Nebulae

Teff 117 000 K

Abell 39Abell 39

Single-shell PN, fully ionized

WIYN [OIII] imageWIYN [OIII] image

Rimno Shell

NGC 3587NGC 3587 KPNO 0.9mKPNO 0.9m

Double-shell PN, but no bright rimpartially ionized, complex morphology

Teff 110 000 K

Example of an Example of an oldold Planetary Nebulae Planetary Nebulae

Teff 114 000 KL 500 L

NGC 2438NGC 2438

Triple-shell configuration, partially recombined 2nd shell ?

Bright ´core´

Brighthalo

NTT H+[NII] NGC 2438NGC 2438 NTT H+[NII]

Bright´core´

Fainthalo

(Data from Corradi et al. 2000)

Sharply boundedSharply boundeddiffuse X-ray emission diffuse X-ray emission from central cavityfrom central cavity

©© M. Guerrero 2005 M. Guerrero 2005

HST [N II]HST HXMM X-rays

central star(no X-ray source)

Central CavityShell

Rim

X-ray detection of hot gas in PNeX-ray detection of hot gas in PNe

NGC 3242

Origin and evolution of Origin and evolution of observed structures ?observed structures ?Origin and evolution of Origin and evolution of observed structures ?observed structures ?

Theoretical concepts Theoretical concepts and models includingand models includingthe essential physics !the essential physics !

Theoretical concepts Theoretical concepts and models includingand models includingthe essential physics !the essential physics !

Hydrodynamical modeling of Planetary Nebulae

Hydrodynamical modeling of Planetary Nebulae

AGB & post-AGB stellar evolution with mass loss Teff (t), L (t), M(t), Vwind (t)

Non-equilibrium physics of a low-density plasma time-dependent ionization / recombination

energy balance due to radiative heating / cooling

Radiation hydrodynamics of stellar winds Dust-driven outflows (AGB) Wind -wind interaction (PPN, PN)

Essential physical ingredients:Essential physical ingredients:

•

1D Rotation, magnetic fields, binarity 2D, 3D

Pot

sdam

NE

BE

L M

odel

s

Example of complex structures: Example of complex structures: NGC 6543NGC 6543

HST color composite

Rotation, magnetic fields, binarity ?

AGB wind modelAGB wind model

Input:Input:MMiniini, , i i stellar evolutionM*(t), L*(t), T*(t), M*(t)Dust propertiesTc, a, I, Qabs(), Qsca()d/ g

ISM

zone

dust-free

5 1014 cm

Slow AGB windV 10 .. 15 km/s

gas & dustgas & dust

•

Output:Output:Wind structure & evolutionr1(t), Vg(r,t), Vd(r,t),g(r,t), d(r,t), Td(r,t)Maps I(x,t,)SEDs F(,t)

The final 350 000 years on the AGBThe final 350 000 years on the AGB

Stellar evolution + two-component hydrodynamics:Stellar evolution + two-component hydrodynamics:

( M( Mii = 3 M = 3 M M Mff = 0.605 M = 0.605 M ))Stellar evolution: Stellar evolution: Blöcker 1995Blöcker 1995

Steffen et al. 1998 / 2005

Dust: Dust: astronomical silicatesastronomical silicates (r) ~ r-, 3V(r) 10 .. 15 km/s

(r) ~ r-, 3V(r) 10 .. 15 km/s

The first 3 000 years of post-AGB evolutionThe first 3 000 years of post-AGB evolution

M=0.595 M

Snapshot: IC 418Snapshot: IC 418

M=0.595 M

Comparison of observation and model: IC 418Comparison of observation and model: IC 418

IC 418

HST H Image

Sharp outer edge of shell: D-type ionization frontFuture rim very faint:wind interaction still weak

Surface brightness profiles:

d [arcsec]

Proto rim

Proto rim

Observed and synthetic line profiles: IC 418Observed and synthetic line profiles: IC 418Central line profiles indicate positive velocity gradient:

2 x 15 km/s2 x 15 km/s

Model nebula (Teff=36300 K, optically thick)Observation © 2003 R. Corradi

[O III] [O III]

[N II][N II]

The formation of a double-shell nebulaThe formation of a double-shell nebula

M=0.595 M

Snapshot: NGC 6826Snapshot: NGC 6826

Rim

Rim

Shell Shell

M=0.595 M

Halo Halo

Observed and modeled surface brightness profiles(Schönberner, Jacob & Steffen, 2005)(Schönberner, Jacob & Steffen, 2005)

Observed and modeled surface brightness profiles(Schönberner, Jacob & Steffen, 2005)(Schönberner, Jacob & Steffen, 2005)

NGC 6826 – [O III] IC 2448 – [O III] NGC 3242 – [O III] NGC 3242 – He II

Observed and synthetic surface brightness distributions

NGC 6826 H NGC 3242 H NGC 1535 H

Comparison of observation and model: NGC 3242Comparison of observation and model: NGC 3242

Stellar evolution + radiation hydrodynamics:

Stellar evolution + radiation hydrodynamics:CCD images (Balick 1987):CCD images (Balick 1987):

H H [O III][O III]

[N II] [N II][He II] [He II]

Observed and synthetic line profiles: NGC 6826Observed and synthetic line profiles: NGC 6826

Rim and shell expand independently (different driving mechanisms)

Model nebula (Teff=67 800 K)Chu et al. 1984(Data © 1999 Lehmann/Hildebrandt)

[O III] [O III]

2 x 8 km/s

Rim

2 x 24 km/sShell

Vrim ~ strength of central star wind & ambient density ( MAGB )

Vshell ~ density gradient of ambient AGB wind & sound speed

Observed expansion velocities of double-shell PNe(Schönberner et al. 2005)(Schönberner et al. 2005)

Observed expansion velocities of double-shell PNe(Schönberner et al. 2005)(Schönberner et al. 2005)

Doppler velocities from Gaussian decomposition

Expansion velocitiesincrease with evolution

Vshell > Vrim

Expansion velocities and kinematic ages of double-shell Planetary Nebulae

(Schönberner, Jacob & Steffen 2005)(Schönberner, Jacob & Steffen 2005)

Expansion velocities and kinematic ages of double-shell Planetary Nebulae

(Schönberner, Jacob & Steffen 2005)(Schönberner, Jacob & Steffen 2005)

Rim Shell

True age [1000 yr] True age [1000 yr]Kin

emat

ic a

ge [

1000

yr]

Kin

emat

ic a

ge [

1000

yr]

Rim Doppler velocity: roughly constant kinematic age useless

Shell Doppler velocity: kinematic age real age [N II] preferred method

The phase of partial recombinationThe phase of partial recombination

M=0.605 M


Rim

Rim

Shell Shell

M=0.605 M

Observation and model: NGC 2438Observation and model: NGC 2438

NTT image, Corradi et al. 2000

H+[N II]

Bright core = RimInner halo = Recombined shell

H+[N II]

Outer halo = Fossil AGB wind

Hydrodynamical interpretation:

PN evolution of low mass CS: no recombination phasePN evolution of low mass CS: no recombination phase

M=0.565 M

Snapshot: Abell 39Snapshot: Abell 39

M=0.565 M

Observation and model: Abell 39Observation and model: Abell 39

Shell swallowed by rim


Observed E-W [O III] slice (Jacoby et al. 2001)

Hydrodynamical model, M=0.565 M (Perinotto et al. 2004)

relic of shell

PN evolution of massive CS: trapped ionizationPN evolution of massive CS: trapped ionization

M=0.696 M


M=0.696 M

rim

shell

Comparison of observation and model: NGC 7027Comparison of observation and model: NGC 7027

Optically thick rim/shell structure

Diffuse outer edge of shell: D-type ionization front beginning recombination


Teff 200 000 K, L 8000 L

HST NICMOS IR image

Schönberner, Jacob, Steffen 2005

rim

shell

Does the AGB mass loss history Does the AGB mass loss history influence the PN evolution ?influence the PN evolution ?

Does the AGB mass loss history Does the AGB mass loss history influence the PN evolution ?influence the PN evolution ?

Structure and expansion properties of Structure and expansion properties of Planetary Nebulae provide constraintsPlanetary Nebulae provide constraintson the final phases of AGB mass loss on the final phases of AGB mass loss


Yes !Yes !Yes !Yes !

Influence of AGB mass loss on PN structureInfluence of AGB mass loss on PN structure

Simple initial model (r) ~ r-2

Simple initial model (r) ~ r-2

H surface brightness

Rim

Shell

Halo

AGB Hydro simulation(r) ~ r-, 3

AGB Hydro simulation(r) ~ r-, 3

H surface brightness

RimShell

Halo

Circumstellar environment and expansion properties of Planetary Nebulae (Schönberner et al. 2005)(Schönberner et al. 2005)

Circumstellar environment and expansion properties of Planetary Nebulae (Schönberner et al. 2005)(Schönberner et al. 2005)

Shell expansion velocity depends only on slope of AGB wind density (and cs)(cf. Chevalier 1997, Shu et al. 2002)

Shell expansion velocity depends only on slope of AGB wind density (and cs)(cf. Chevalier 1997, Shu et al. 2002)

Initial AGB wind density:

r-

2.5 < < 3.3

Typical double-shell PNe:25 km/s < Vshell < 40 km/s

(Vsh

ell-V

AG

B)

/ cs

The halo of NGC 6826The halo of NGC 6826

Inner halo: I ~ r –, 5 .. 7

Outer edge: last TP on AGB

~ r –, 3 .. 4

(Corradi et al. 2003)



AGBAGB ~ r ~ r ––, , 2.52.5 < < < < 3.53.5

Mass loss increases Mass loss increases towards end of AGBtowards end of AGBMass loss increases Mass loss increases towards end of AGBtowards end of AGB

AGB: > 2.5 (Kwok et al. 2002)

PPN: 3 < < 4 (Hrivnak & Bieging 2005)

How does the How does the central star windcentral star windinfluence the PN evolution ?influence the PN evolution ?

How does the How does the central star windcentral star windinfluence the PN evolution ?influence the PN evolution ?

Comparison of two different wind models:

Pauldrach et al. (1988)Pauldrach et al. (2004)

Pauldrach et al. (1988)Pauldrach et al. (2004)

Influence of central star wind on rim structureInfluence of central star wind on rim structure

CSPN wind: Pauldrach et al. (1988) CSPN wind: Pauldrach et al. (2004)

Rim: density gradient & velocity gradient reversed, increased width

ConclusionsConclusions

Time-dependent 1D modeling combining Single star evolution with mass loss + radiation-hydrodynamics of stellar winds + non-equilinrium low-density plasma physicscan explain the observed basic nebular structures:

X-ray emission of the central hot bubble radial intensity profiles in various emission lines internal kinematics and expansion properties structure and evolution of PN haloes

Models allow a classification of observed PNeModels allow a classification of observed PNein terms of evolutionary state and central star massin terms of evolutionary state and central star mass

DiscussionDiscussion & Outlook & Outlook

Main uncertainties of present models:Main uncertainties of present models:Mass loss during end of AGB and beyond Transition times

Improved models:Improved models: New AGB and post-AGB tracks with mass loss PN evolution for different metallicities PN evolution for Wolf-Rayet (WC) central stars

Documents

Hydrodynamical Interpretation of Basic Nebular Structures M. Steffen & D. Schönberner M. Steffen & D. Schönberner Abell 39 (WIYN )