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Do Most Planetary Systems Form in Star Clusters

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Do Most Planetary Systems Form in Star Clusters Powered By Docstoc
					Do Most Planetary Systems Form in Star Clusters?
John Bally
Nathaniel Cunningham1,2 Nick Moeckel1 Nathan Smith3 Guy Stirngfellow1 Josh Walawender4 + Bolocam Galactic Plane Survey team: J. Aguirre, N. J. Evans, J. Glenn, M. Nordhaus, J. Williams, ….

Center for Astrophysics and Space Astronomy

University of Colorado, Boulder, CO

Outline
• Dense cores in GMCs => dense star clusters - 50 to 90% of stars - Clusters and associations with up to 106 stars - Dissolve in 1 to 100 Myrs - Massive stars: 8 to > 130 Mo => UV, SN - Time scales: t* ~ M* / (dM/dt) ~ 105 yr tcluster ~ few x 106 yr • Impacts on Planet formation - UV: Grain growth + sedimentation + UV => Increase metallicity in disk, => Prompt planetesimal formation - Late-phase, secondary accretion - Injection of SLRs (26Al, 60Fe, …)

Dark Energy: Expansion is accelerating!

M81

The Galactic Plane: (Bolocam Galactic Plane Survey)

Dense cloud cores: Dust continuum at  = 1.1 mm

Giant Molecular Clouds: 13CO at  = 2.6 mm

Bolocam 1.1 mm: 1 square degree near W3

HH 46/47 NTT [OII] Ha [SII]386567 mm Bally & Reipurth (06 “Birth of Stars & Planets” CUP = BR06)

HH 46/47 Spitzer (Noriega-Crespo 04; BR06)

H2 PAH36458 mm

HH 46/47 (Hartigan et al. 05, AJ BR06)

HST 1994

HH 46/47 (Hartigan et al. 05, AJ BR06)

HST 1997

Galactic Ecology: Star Formation & the Interstellar Medium

500 pc
< 10 Myr bubbles

Sun

30 - 50 Myr old Gould's Belt /Lindblad Ring

de Zeeauw et al.

Star & Planet Formation
Shrink size by 107; increase density by x 1021 !

• Giant Molecular Cloud Core
Raw material for star birth • Gravitational Collapse & Fragmentation Proto-stars, proto-binaries, proto-clusters

• Rotation & Magnetic Fields
Accretion disks, jets, & outflows • Planets Most may form in clusters!

C. Lada

Giant Molecular Clouds
The Raw Material of Star and Planet Formation • Massive: M = 103 to 106 x MSun • Molecular: H2 (70%) He (29%) Trace Molecules: (1%) CO, OH, CS, HCO+, organics, … , • Cold: T = 5 to 50 K • Dense: n(H2) = 100 to > 105 cm-3 • Giant: L = 10 to 100 light years

Orion A

12CO

230 GHz = 1.3 mm

Orion A

13CO

220 GHz = 1.3 mm

The Perseus Molecular Cloud 13CO V = 2 to 11 km/s

NGC 1333

IC 348

Miesch & Bally (94); BR06

IRAS 03235+3004

NGC 1333

Ha, [SII] Walawender, Bally, Reipurth (06) Spitzer/IRAC Jorgensen et. (06)

Serpens cluster (Class I, II) Spitzer Space Telescope: 3.5, 4.6, 8 mm)

Serpens cluster (Class I, II) VLT + adaptive optics: 1.2, 1.6, 2.2 mm)

NGC 3603: 50 massive stars + 104 low mass stars VLT + adaptive optics: 1.2, 1.6, 2.2 mm)

The Carina Nebula (CTIO Schmidt)

The Carina Nebula

 Carinae Nebula: Trumpler 14 region

Pillars with jets

Tr 14 cluster (< 3 Myr)

Trumpler 14 Dark globule: faces  Car

Jet ?

Twin jets from YSOs in Pillars near Tr 14

Bipolar jet

YSO

Bate, M. R., Bonnell, I. A., Bromm, V., 2002, MNRAS, 332, L65-L68

SPH:
QuickTime™ and a Cinepak decompressor are needed to see this picture.

No radiation No B No outflows.

QuickTime™ and a GIF decompressor are needed to see this picture.

Nickolas Moeckel (2006) SPH: Massive star capture-formed binary: Disk orientation change

Ceph A precessing jet: P ~ 2 x 103 yr ? Cunningham, Moeckel, & Bally
Pulsed, precessing jet from HW2 (H2 axes in solid; radio-jet ----) Second flow from HW3c (unperturbed bipolar outlfow; white solid and dashed)

QuickTime™ and a Sorenson Video 3 decompressor are needed to see this picture.

The Orion Star Forming Complex

AEAur 150 km/s
PERSEUS

L1551

ORION

i Ori

m Col 117 km/s

Wei-Hao Wang

Infrared view of winter sky (10 - 120 mm)

The Orion/Eridanus Bubble (Ha): d=180 to 500pc; l > 300 pc Orion OB1 Association: ~40 > 8 M stars: ~20 SN in 10 Myr 
Ori (< 3 Myr)

1a (8 - 12 Myr; d ~ 350 pc)) 1b (3 -6 Myr; d ~ 420 pc) 1c (2 - 6 Myr; d ~ 420 pc) 1d (<2 Myr; d ~ 460 pc)

Barnards's Loop

Eridanus Loop

Orion Molecular Clouds Orion B

13CO

2.6 mm

Orion Nebula

Orion A

Orion below the Belt:
NGC 2024 (OB1 d)

Horsehead Nebula
s Orionis (OB1c) NGC 1981 NGC 1977

Ori OB1c

Orion Nebula

Ori OB1d

i Ori NGC1980: Source of m Col + AE Aur ; V ~ 150 km/s runaways, 2.6 Myr ago

Orion Nebula

OMC 1 Outflow (H2 t = 500 yr) BNKL (L = 105 Lo t << 105 yr)

Trapezium (L = 105 Lo t < 105 yr )

OMC1-S (L = 104 Lo , t < 105 yr)

0.5 – 2.2 mm 104 AU

Orion BN/KL H2 fingers E ~ 1048 erg

Dynamical Decay of Sub-cluster of massive stars
~ 500 years ago
(N. Cuningham 2006 PhD thesis)

2.12 mm H2 (blue) 11.7 mm (orange)

Smith et al. (2005)
+ Cunningham (2008)

Trapezium cluster

massive stars

Low mass stars

Taurus disks & jets: Stapelfeldt et al.

Keck AO IR

HST H-alpha

2.12 mm H2 0.63 mm [OI] => Soft UV photo-heating of disk surface (Kassis et al. 2007)

Growing grains: Orion 114-426

(Throop et al. 2001)

Growing grains:

Si 10 mm feature (Shuping et al. 2006)

d181-825 “Beehive” proplyd

Chandra COUP

Jet

Star

8 ; 10

1280 AU

20 cm

kT ~ 0.57 keV & 3.55 keV NH ~ 8 x 1020 cm-2 (soft) NH ~ 6 x 1022 cm-2 (hard)

(Kastner et al. 2005, ApJS, 160, 511)

d181-825 “Beehive” proplyd

X-ray absorption: NH ~ 8 x1020 cm-2 But, foreground AV ~ 1 mag ! H-alpha:

ne(rI) = 2.6 x 104 cm-3 dM/dt = 2.8 x 10-7 Mo yr-1
Neutral Column: (from 50 AU, V = 3 km/s) NH(RI) = 2.2 x 1021 V3-1 r50-1

Photo-ablation flow metal depleted!
(Kastner et al. 2005, ApJS, 160, 511)

Flux History, Typical 1 Mo Star

• • • • •

Flux varies by 1000x Peak flux approaches 107 G0. Intense close encounters with core. There is no `typical UV flux.’ Impulsive processing.

6 – 13.6 eV UV photons

6 – 13.6 eV UV photons

6 – 13.6 eV UV photons

6 – 13.6 eV UV photons

> 13.6 eV photons 6 – 13.6 eV UV photons

> 13.6 eV photons 6 – 13.6 eV UV photons

Stellar wind > 13.6 eV photons 6 – 13.6 eV UV photons

Stellar wind > 13.6 eV photons 6 – 13.6 eV UV photons

Stellar wind > 13.6 eV photons 6 – 13.6 eV UV photons

Stellar wind > 13.6 eV photons 6 – 13.6 eV UV photons

Stellar wind > 13.6 eV photons 6 – 13.6 eV UV photons

Stellar wind > 13.6 eV photons 6 – 13.6 eV UV photons

rG = GM/c2 C ~ 3 km/s

Stellar wind > 13.6 eV photons 6 – 13.6 eV UV photons

Stellar wind > 13.6 eV photons 6 – 13.6 eV UV photons

Stellar wind > 13.6 eV photons 6 – 13.6 eV UV photons

Stellar wind > 13.6 eV photons 6 – 13.6 eV UV photons

Stellar wind > 13.6 eV photons 6 – 13.6 eV UV photons

Stellar wind > 13.6 eV photons 6 – 13.6 eV UV photons

Stellar wind > 13.6 eV photons 6 – 13.6 eV UV photons

rG = GM/c2
C ~ 10 km/s

Stellar wind > 13.6 eV photons 6 – 13.6 eV UV photons

Stellar wind > 13.6 eV photons 6 – 13.6 eV UV photons

Conclusions
• Most stars form in transient, but short-lived clusters • Inherit the complex organics from parent cloud • Forming planetary systems impacted by massive stars time-scale for planet formation ~ lifetime of massive stars • UV photo-ablation: grain growth + sedimentation + UV => Prompt planetesimal formation by Gravitational Instability • Time-scale for star formation ~ 105 years << time-scale for cluster birth => Secondary accretion during late phases of planetary formation Add fresh H2 after giant planet core formation? => Supernovae: 60Fe, …. , Absorb by cores, accrete onto disk “Collect and Pollute”

The End


				
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