Architecture of planetary systems:HR 8799 and ε Eridani

Martin ReidemeisterA. V. Krivov1, T. Lohne1, S. Muller1, T. O. B. Schmidt1, S. Fiedler1,

C. C. Stark2 and J.-C. Augereau3

1 Astrophysikalisches Institut und Universitats-Sternwarte JenaSchillergaßchen 2-3, 07745 Jena

2 Department of Physics, University of MarylandBox 197, 082 Regents Drive, College Park, MD 20742-4111

3 Laboratoire d’Astrophysique de Grenoble, CNRS UMR 5571Universite Joseph Fourier, Grenoble, France

15.11.2010

M. Reidemeister et al. (AIU Jena) Architecture of planetary systems 15.11.2010 1 / 13

Content

1 Introduction

2 HR 8799

3 ε Eridani

4 Summary

M. Reidemeister et al. (AIU Jena) Architecture of planetary systems 15.11.2010 2 / 13

Introduction

DefinitionArchitecture of planetary system:

starplanet(s)dustplanetesimal belts(source of dust)

Motivationmultiple interactions betweendust, planetesimals and planetsconstrain planet masses,eccentricity, inclinationplanetesimals are remnants ofplanet formation

M. Reidemeister et al. (AIU Jena) Architecture of planetary systems 15.11.2010 3 / 13

Introduction

DefinitionArchitecture of planetary system:

starplanet(s)dustplanetesimal belts(source of dust)

Motivationmultiple interactions betweendust, planetesimals and planetsconstrain planet masses,eccentricity, inclinationplanetesimals are remnants ofplanet formation

M. Reidemeister et al. (AIU Jena) Architecture of planetary systems 15.11.2010 3 / 13

Content

1 Introduction

2 HR 8799

3 ε Eridani

4 Summary

M. Reidemeister et al. (AIU Jena) Architecture of planetary systems 15.11.2010 4 / 13

HR 8799 – Introduction

ParametersA5 V star with d = 39.4 pcage of . 50 Myr Reidemeister et al. (2009)

(20 Myr up to 1 Gyr)γ Doradus (variable star)λ Bootis (metalpoor Pop. I)

Observationsstrong IR excess (IRAS, ISO)Sadakane&Nishida (1986), Zuckerman&Song (2004),

Moor et al. (2006), Rhee et al. (2007)

Spitzer/IRS spectrumJura et al. (2004), Chen et al. (2006)

3 directly imaged planetsat 68, 38 & 24 AUwith MP =5–13MJup

100

101

102

10310

−4

10−2

100

wavelength [µm]

flux

[Jy]

Marois et al. (2008)

M. Reidemeister et al. (AIU Jena) Architecture of planetary systems 15.11.2010 5 / 13

HR 8799 – The planets

toE

arth

System' sangularmomentum

System' s

symmetry plane

Sky planeLine of nodes

N

E

W

i

Resultsinclination of 20–30◦

(rotational period: 13–30◦)rotation angle of 0–50◦

slipping in 1:2:4 resonance

2:1 b-c

2:1 c-d

duration of stability in years

0 20 40 60 80 100 120 140 160 180

rotation angle [deg]

0

5

10

15

20

25

30

35

40

45

incl

inat

ion

angl

e [d

eg]

103

104

105

106

107

108

2:1 b-c

2:1 c-d

duration of stability in years

M. Reidemeister et al. (AIU Jena) Architecture of planetary systems 15.11.2010 6 / 13

HR 8799 – The dust

100AU

d

cb

outer dust disk

outer ring ofplanetesimals

planetesimals

inner ring of

and dust

dust ringsouter ring & 100 AUMdust ≈ 4× 10−2M⊕

inner ring 2–10 AUMdust ≈ 10−5M⊕

101

102

10 100 1000

Fν

[mJy

]

λ [µm]

101

102

10 100 1000

Fν

[mJy

]

λ [µm]

ring dring cdring bcring bbest fit

101

102

10 100 1000

Fν

[mJy

]

λ [µm]

M. Reidemeister et al. (AIU Jena) Architecture of planetary systems 15.11.2010 7 / 13

HR 8799

Stability

Dust mass

Ring position

Planetary mass

Inclination

Rotational period

Age

M. Reidemeister et al. (AIU Jena) Architecture of planetary systems 15.11.2010 8 / 13

Content

1 Introduction

2 HR 8799

3 ε Eridani

4 Summary

M. Reidemeister et al. (AIU Jena) Architecture of planetary systems 15.11.2010 9 / 13

ε Eridani

ParameterK2 V star at d = 3.2 pcage . 1 Gyr DiFolco et al. (2004)

SW: 30M� Wood et al. (2002)

“Kuiper belt” analog in sub-mmaround 65 AU Greaves et al. (1998, 2005)

assumed outer planetRV planet at 3.4 AU Hatzes et al. (2000)

A: e = 0.70 Benedict et al. (2006)

B: e = 0.25 Butler et al. (2006)

Spitzer/IRS spectrum indicateswarm dust at a few AU Backman et al. (2009)

“The cold origin of the warm dust”

M. Reidemeister et al. (AIU Jena) Architecture of planetary systems 15.11.2010 10 / 13

ε Eridani

ParameterK2 V star at d = 3.2 pcage . 1 Gyr DiFolco et al. (2004)

SW: 30M� Wood et al. (2002)

“Kuiper belt” analog in sub-mmaround 65 AU Greaves et al. (1998, 2005)

assumed outer planetRV planet at 3.4 AU Hatzes et al. (2000)

A: e = 0.70 Benedict et al. (2006)

B: e = 0.25 Butler et al. (2006)

Spitzer/IRS spectrum indicateswarm dust at a few AU Backman et al. (2009)

outer ring (55-90AU)

oute

r planet

intermediate (10-55AU)

inner (<10AU)

planet 'A'planet 'B'

0

0.5

1

1.5

2

10 100 1000

exce

ss fl

ux [J

y]

wavelength [µm]

IRASMIPS

MIPS (SED)SHARC II

SCUBA

“The cold origin of the warm dust”

M. Reidemeister et al. (AIU Jena) Architecture of planetary systems 15.11.2010 10 / 13

ε Eridani – ResultsSpectral energy distribution

0

0.5

1

1.5

2

10 100 1000

exce

ss f

lux [

Jy]

wavelength [µm]

Planet A: a=3.4AU, e=0.70

0-10AU, 0.05-1.42µm, q=3.010-90AU (ACE)

totalIRASMIPS

MIPS (SED)SHARC II

SCUBA

M. Reidemeister et al. (AIU Jena) Architecture of planetary systems 15.11.2010 11 / 13

ε Eridani – ResultsSurface brightness profile

10-3

10-2

10-1

100

101

0 5 10 15 20 25 30 35 40

su

rfa

ce

brig

htn

ess [

mJy/a

rcse

c2]

distance [arcsec]

24µm70µm

160µmSpitzer/MIPS

PSF

M. Reidemeister et al. (AIU Jena) Architecture of planetary systems 15.11.2010 12 / 13

Summary

HR 8799young system (. 50 Myr)- planets with lower mass- high dust masssolar system like architecture:two dust ringsgas giants in between

ε Eridanigap in the sub-mm indicatesan outer planetinner planetesimal beltunstablemassive dust disk (10−3M⊕)but transport dominateddust can stem from outer ringand supply the inner system

M. Reidemeister et al. (AIU Jena) Architecture of planetary systems 15.11.2010 13 / 13