Inga Kamp

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Inga Kamp The role of the central star for
the structure of protoplanetary disks Peter
Woitke, Wing-Fai Thi, Ian Tilling (all Edinburgh)
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Protoplanetary Disks and Planet Formation

• Dust dynamics are controlled by gas, even at late
  times !
• dust substructure
• dust coagulation
• dust settling

Reverse ?p/?r at 70 AU Klahr Lin 2001
HR4796 NICMOS 1.6 mm Schneider et al. 1999
8 Myr
mJy/pixel
Barge Sommeria 1995, Johansen et al. 2006,
2007
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Outline

• Various planet forming environments (BD - T
  Tauri - Herbig)
• Second generation disk structure modeling
• How do observations inform us about the
  star-disk
• interaction ?

4
Outline

• Various planet forming environments (BD - T
  Tauri - Herbig)
• Second generation disk structure modeling
• How do observations inform us about the
  star-disk
• interaction ?

5
Outline

• Various planet forming environments (BD - T
  Tauri - Herbig)
• Second generation disk structure modeling
• How do observations inform us about the
  star-disk
• interaction ?

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Protoplanetary Disk Models

• Key astrophysical questions
• What is the environment in which planets form ?
• disk structure - boundary conditions for planet
  formation
• Can planets form around stars different from our
  Sun ?
• star-disk interaction - impact on disk
  structure and dispersal

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Outline

• Various planet forming environments (BD - T
  Tauri - Herbig)
• Second generation disk structure modeling
• How do observations inform us about the
  star-disk
• interaction ?

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Disk properties
Dust in BD disks evolves on same time scale as T
Tauri disks Inner disk clearing occurs much
faster in T Tauri disks Dust models fit BD, T
Tauri and Herbig SEDs in the same way indicating
the first steps of planetesimal formation in all
cases some BD SEDs require flaring disks,
others flat low statistics
2 BDs _at_ 2 and 10 Myr
Sterzik et al. 2004 8?m
excess _at_ 5 Myr Carpenter et al.
2006 Pascucci et al. 2003, Allers et al.
2006, Bouy et al. 2008
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Disk properties
Kessler-Silacci et al. 2007
Pascucci et al. 2009
lower HCN/H2C2 ratios in the disks around brown
dwarfs weaker and more processed silicate
features
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Outline

• Various planet forming environments (BD - T
  Tauri - Herbig)
• Second generation disk structure modeling
• How do observations inform us about the
  star-disk
• interaction ?

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Protoplanetary Disk Models
physical structure
comparison with observation
radiative transfer
chemical composition
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Protoplanetary Disk Models
surface density ? ?0 (r/r0)-p dust
temperature T T0 (r/r0)-q disk scale height
H H0 (r/r0)-e
physical structure
comparison with observation
radiative transfer
chemical composition
e.g. Menard et al. Pinte et al. 2006
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Protoplanetary Disk Models
surface density ? ?0 (r/r0)-p dust
temperature 2D continuum RT disk scale height
H (cs2 r3/GM)0.5
physical structure
comparison with observation
radiative transfer
chemical composition
e.g. DAlessio et al. 1998, Dullemond et al.
2002
Gas chemical modeling on top of fixed density
structure
e.g. Aikawa et al. 2002, Semenov et al. 2008
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Protoplanetary Disk Models
physical structure
hot flaring surface
comparison with observation
line radiative transfer
chemical composition
cold midplane
molecule freeze-out
rich molecular chemistry
atomic/ionized
e.g. Aikawa et al. 2002, Kamp Dullemond
2004 PPV chapters Dullemond et al. 2007,
Bergin et al. 2007
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Protoplanetary Disk Models
ProDiMo
physical structure
comparison with observation
radiative transfer
chemical composition
Woitke, Kamp, Thi 2009
Similar approaches have been followed by other
groups Nomura Millar 2005, Gorti Hollenbach
2004, 2008
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Chemistry
stationary solution with modified Newton-Raphson
algorithm (switch to time-dependant)
65 species H, H, H-, H2, H2, H3
He, He C, C,
CO, CO, CO2, CO2, HCO, HCO, H2CO
CH, CH, CH2, CH2, CH3, CH3, CH4, CH4,
CH5 O, O, O2, O2, OH, OH
H2O, H2O, H3O
N, N, NH, NH, NH2, NH2, NH3, NH3, N2, HN2
CN, CN, HCN, HCN, NO, NO
Si, Si, SiH, SiH, SiO,
SiO, SiH2, SiOH S, S, Mg,
Mg, Fe, Fe
--gt plus CO,
H2O, CO2, CH4, NH3 ice
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Heating and cooling
Heating
photo-electric heating, PAH heating, viscous (a)
heating, cosmic ray, C photo-ionisation, coll.
de-excitation of H?2 , H2 on grains, H2
photodissociation, IR background line
heating thermal accomodation on grains, OI, CII,
CI ?ne-structure cooling, CO ro-vibrational (110
levels, 243 lines), o/p H2O rotational (45/45
levels, 258/257 lines), o/p H2 quadrupole (80/80
levels, 803/736 lines), SiII, SII, FeII
semi-forbidden (80 levels, 477 lines), Ly a, MgII
hk, OI 6300Å
Cooling
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Heating and cooling
Heating
photo-electric heating, PAH heating, viscous (a)
heating, cosmic ray, C photo-ionisation, coll.
de-excitation of H?2 , H2 on grains, H2
photodissociation, IR background line heating,
(X-ray heating) thermal accomodation on grains,
OI, CII, CI ?ne-structure cooling, CO
ro-vibrational (110 levels, 243 lines), o/p H2O
rotational (45/45 levels, 258/257 lines), o/p H2
quadrupole (80/80 levels, 803/736 lines), SiII,
SII, FeII semi-forbidden (80 levels, 477 lines),
Ly a, MgII hk, OI 6300Å
Cooling
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Protoplanetary Disk Models
interstellar UV
stellar UV
stellar X rays
soft inner and outer edges Hartmann et al.
1989, Hughes et al. 2008,

Woitke, Kamp Thi 2009
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The Thermal Balance
Photoelectric heating of the gas
e-
stellar photons
small grains a ltlt l (e.g. PAHs) yield ??
e-
e-
e-
large grains a gtgt l (micron sized) yield ??
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The Thermal Balance
Photoelectric heating of the gas
e-
stellar photons
small grains a ltlt l (e.g. PAHs) yield ??
e-
e-
e-
large grains a gtgt l (micron sized) yield ??
Abbas et al. 2006
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Impact of UV Irradiation
HD104237
H2
OVI
H2, CO photodissociation
C ionization
FUSE Apr 2000 STIS
Oct 2001 May
2001 GHRS Nov 1994
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Impact of UV Irradiation
UV excess
time
5000 K
500
10
50
80
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Impact of UV Irradiation
UV excess
time
0 log n(OH)/n(tot)
-5
-14
-10
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Protoplanetary Disk Models
interstellar UV
stellar UV
stellar X rays
soft inner and outer edges Hartmann et al.
1989, Hughes et al. 2008,

Woitke, Kamp Thi 2009
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The Thermal Balance
TW Hya LX 1030 erg/s Kastner et al.
1997 Nomura et al. 2007
X-ray heating of the gas
Primary ionization
stellar X-rays
e-
124.0 Å
1.24 Å

e-
Secondary ionization

e-
Glassgold et al. 2004, Meijerink et al. 2008
Auger electrons
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Protoplanetary Disk Models
Flaring disk structure early Sun M 1 M? L
1 L? Teff 5800 K Mdisk 10-2 M? 0.5-500
AU dust 90 Mg2SiO4 10 Fe 0.1-10 ?m (2.5)
Woitke, Kamp, Thi
2009
X-ray source _at_ 20 R? to irradiate disk midplane
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Protoplanetary Disk Models
Flaring disk structure Herbig star M 2.2
M? L 32 L? Teff 8500 K Mdisk 10-2
M? 0.5-500 AU dust 90 Mg2SiO4 10 Fe 0.1-10
?m (2.5)
T Tauri
Herbig Ae
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Protoplanetary Disk Models
Herbig Ae
T Tauri
decreasing disk mass
Flaring disk structure Herbig star M 2.2
M?
dust L 32 L?
90 Mg2SiO4 Teff 8500 K
10 Fe Mdisk 10-2,
10-3, 10-4 M? 0.05-200 ?m
(3.5) 0.5-700 AU
self-similarity
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Outline

• Various planet forming environments (BD - T
  Tauri - Herbig)
• Second generation disk structure modeling
• How do observations inform us about the
  star-disk
• interaction ?

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Probes of UV Irradiation OI, OH
OH photodissociation layer OH n ?
O H O denotes the 1D2 excited level
(decay emits a 6300 Å photon)
460 AU
WFPC2
Bally et al. 2000, Störzer Hollenbach 1998,
Acke et al. 2005
Mandell et al. 2008, Salyk et al. 2008
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Probes of UV Irradiation OI, OH
OH photodissociation layer OH n ?
O H O denotes the 1D2 excited level
(decay emits a 6300 Å photon)
VLT/UVES HD97048
normalized flux
velocity km/s
Bally et al. 2000, Störzer Hollenbach 1998,
Acke et al. 2005
Mandell et al. 2008, Salyk et al. 2008
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Probes of UV, X-ray Irradiation CO, H2
Fluorescence excitation vs. thermal emission CO
UV pumping of electronic states gt cascade into
high v levels H2 UV (Lyman Werner bands) or
X-rays (collisions with fast e-)
v1-0 S(1), S(0), v2-1 S(1) NIR Carmona et
al. 2008
Brittain et al. 2007
see talk by Gerrit van der Plas
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Probes of UV, X-ray Irradiation CO, H2
Fluorescence excitation vs. thermal emission CO
UV pumping of electronic states gt cascade into
high v levels H2 UV (Lyman Werner bands) or
X-rays (collisions with fast e-)
Brittain et al. 2007
see talk by Gerrit van der Plas
S(1), S(2), S(4) pure rotational MIR lines
Bitner et al. 2008
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Probes of X-ray Irradiation NeII
see talk by Richard Alexander
Glassgold et a. 2007, Pascucci et al. 2007,
Lahuis et al. 2007, Meijerink et al. 2008
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Probes of gas-dust decoupling
C
H
Pietu et al. 2007
D
E
0
50
100
150
200
R (AU)
temperatures derived from gas lines at the
surface are higher than dust temperatures gt
support for decoupling of gas and dust in the
surface layers
D 13CO 3-2 E 13CO 1-0
C 12CO 2-1 H HCO 4-5
van Zadelhoff et al. 2001
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Probes of gas-dust decoupling
OI emission
MIR dust emission
Fedele et al. 2008
dust is flat (self-shadowed) and gas is
flaring gt support for decoupling of gas and dust
in the surface layers
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GASPS A Herschel Key program
GAS evolution in Protoplanetary Systems (PI Dent)
200 disks distributed over spectral type, age,
and disk mass CII, OI, CO and H2O
lines Aim probe the gas mass evolution
throughout the planet forming phase
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GASPS A Herschel Key program
physical structure
line radiative transfer
comparison with observation
chemical composition
Monte Carlo line radiative transfer understand
where the line originates and then put resolution
there !!
Hogerheijde, van der Tak 2000
Kamp, Tilling, Woitke, Thi, Hogerheijde
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Key points to take home

• Models predict that stellar UV and X-ray
  radiation shape the
• disk structure and chemistry and we actually
  observe that !
• Individual gas lines DO NOT probe total disk
  mass !
• but we keep trying with multiple tracers
• Gas lines DO probe the physical and chemical
  conditions in the
• region where they arise (interplay between
  radiative transfer
• and chemical structure)

and we try hard with GASPS to find the
desperately wanted 10-4 M? disks
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Thank You !