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The COMPLETE Survey of Star-Forming Regions: Nature vs. Nurture
Alyssa A. GoodmanHarvard-Smithsonian Center for Astrophysics
cfa-www.harvard.edu/~agoodman
COMPLETE
The COordinated Molecular Probe Line Extinction Thermal Emission Survey Alyssa A. Goodman, Principal Investigator (CfA)
João Alves (ESA, Germany)Héctor Arce (Caltech)
Paola Caselli (Arcetri, Italy)James DiFrancesco (HIA, Canada)
Mark Heyer (UMASS/FCRAO)Di Li (CfA)
Doug Johnstone (HIA, Canada)Naomi Ridge (UMASS/FCRAOCfA)Scott Schnee (CfA, PhD student)
Mario Tafalla (OAS, Spain)Tom Wilson (MPIfR)
Nature Nurture
Shu, Adams & Lizano 1987
CorporationsEnvironmentalist
s
Shu, Adams & Lizano 1987
TheoryObservatio
n
Shu, Adams & Lizano 1987
Molecular or Dark Clouds
"Cores" and Outflows
Star Formation 101: A “Natural” Framework
Jets and Disks
Extrasolar System
1 p
c
On the way to Star Formation 201
Ten Years Ago, this picture was OK…but now I know that:Structures in a turbulent, self-
gravitating, flow are highly transientOutflows are episodicYoung stars can move rapidlyEnergetically significant spherical
outflows (e.g. SNe, winds) are common in star-forming regions
How do I know “that”?
Optical imagingNear-infrared imaging Thermal dust imaging
Molecular spectral-line mapping
MHD Simulations
Spectral Line MappingVelocitySpectral Line Observations
Mountain RangeNo loss ofinformatio
n
Loss of1 dimension
Star Forming Regions as Turbulent Flows: MHD Simulations
Stone, Gammie & Ostriker 1999•Driven Turbulence; M K; no gravity•Colors: log density•Computational volume: 2563
•Dark blue lines: B-field•Red : isosurface of passive contaminant after saturation
=0.01 =1
T / 10 K
nH 2 / 100 cm-3 B / 1.4 G 2
Simulated map, based on work of Padoan, Nordlund, Juvela, et al.Excerpt from realization used in Padoan, Goodman &Juvela 20023
Characterizing Spectral Line Maps of Observed & Simulated
“Turbulent “Flows
The Spectral Correlation Function
(SCF)
See also PCA analysis (Heyer et al.)
& many other methods
“Equipartition”Models
Summary Results from SCF Analysis
Fallo
ff o
f C
orr
ela
tion
wit
h S
cale
Magnitude of Spectral Correlation at 1 pc
Padoan, Goodman
& Juvela 2003
“Reality”
Scaled “Superalfvenic”Models
“Stochastic”Models
Do existing turbulence simulations “match” molecular clouds?
13CO maps Super-Alfvénic MHD Simulations
Fallo
ff o
f Sp
ect
ral C
orr
ela
tion
wit
h S
cale
Magnitude of Spectral Correlation at 1 pc
Padoan, Goodman & Juvela 2003
Structures are Highly Transient
Bate, Bonnell & Bromm 2002
•MHD turbulence gives “t=0” conditions; Jeans mass=1 Msun
•50 Msun, 0.38 pc, navg=3 x 105 ptcls/cc
•forms ~50 objects
•T=10 K
•SPH, no B or •movie=1.4 free-fall times
QuickTime™ and aCinepak decompressorare needed to see this picture.
On the way to Star Formation 201
Structures in a turbulent, self-gravitating, flows are highly transient
Outflows are episodic
Young stars can move rapidly
Energetically significant spherical outflows (e.g. SNe, winds) are common in star-forming
regions
Episodic Outflows, from Moving Sources
10-5
10-4
10-3
10-2
10-1
100
Mass
[M
sun]
0.12 3 4 5 6 7 8
12 3 4 5 6 7 8
102
Velocity [km s-1]
Power-law Slope of Sum = -2.7(arbitrarily >2)
Slope of Each Outburst = -2as in Matzner & McKee 2000
Episodicity changes Energy/Momentum Deposition (time)
(Some) Young stars may zoom through ISM
L1448
Bach
iller
et
al. 1
990
B5
Yu B
illaw
ala
& B
ally
199
9
Lada &
Fic
h 1
99
6
Bach
iller,
Tafa
lla &
Cern
icharo
19
94
Position-Velocity Diagrams
show YSO Outflows are Highly Episodic
Outflow Episodes:Position-Velocity Diagrams
Figure
fro
m A
rce &
Goodm
an 2
00
az1
a
HH300
NGC2264
10-5
10-4
10-3
10-2
10-1
100
Mass
[M
sun]
0.12 3 4 5 6 7 8
12 3 4 5 6 7 8
102
Velocity [km s-1]
Episodic Outflows: Steep Mass-Velocity Slopes Result from Summed
Bursts
Power-law Slope of Sum = -2.7(arbitrarily >2)
Slope of Each Outburst = -2as in Matzner & McKee 2000
Arce & Goodman 2001b
Powering source of (some) outflows may zoom through ISM
1 pc
“Giant” Herbig-
Haro Flow from
PV Ceph
Image from Reipurth, Bally & Devine 1997
PV Ceph
Episodic ejections from a
precessing or wobbling
moving moving source
Goodman & Arce 2003
PV Ceph is moving at ~10 km s-1
Goodman & Arce 2003
“Plasmon” Model of PV Ceph4x1018
3
2
1
0
y knot positions (cm)
-4x1017
-2 0
x knot posns. w.r.t. star "now" (cm)
500x1015
400
300
200
100
0
Dis
tance
alo
ng x
-dir
ect
ion (
cm)
15x103
1050
Elapsed Time since Burst (Years)
70
60
50
40
30
20
10
0
Sta
r-Knot D
iffere
nce
/Sta
r Off
set (P
erce
nt)Knot
Star
Star-KnotDifference
Star-KnotDifference
(%)
Initial jet 250 km s-1; star motion
10 km s-1
Goodman & Arce 2003
“Plasmon” Model of PV Ceph4x1018
3
2
1
0
y knot positions (cm)
-4x1017
-2 0
x knot posns. w.r.t. star "now" (cm)
1
2
3
4
5
6
7
8
9
10
"Dynamical Time"/Elapsed Time
3.0x1018
2.52.01.51.00.50.0
Distance of Knot from Source (cm)
Goodman & Arce 2002
For an HH object at 1 pc from source, dynamical time calculation overestimates age by factor of ten.
“Giant” Outflows, c. 2002
See references in H. Arce’s Thesis 2001
The action of multiple outflows in NGC 1333?
SCUBA 850 mm Image shows Ndust (Sandell & Knee
2001)Dotted lines show CO
outflow orientations (Knee & Sandell 2000)
On the way to Star Formation 201
Structures in a turbulent, self-gravitating, flows are highly transient
Outflows are episodic
Young stars can move rapidly
Energetically significant spherical outflows (e.g. SNe, winds) are common in star-forming
regionsPreview Now, More Later!
COMPLETE Preview:Discovery of a Heated Dust Ring in
Ophiuchus
Goodman, Li & Schnee 2003
2 pc
COMPLETE Preview: Great
Bubble in Perseus
QuickTime™ and aTIFF (LZW) decompressorare needed to see this picture.
Does fecundity = demise?
Bipolar outflows from young stars+
Stellar Winds (& photons) from older stars+
Large Explosions (SNe, GRBs)
All have the power both to create & destroy
Nature Nurture
Shu, Adams & Lizano 1987
Star Formation 201 “Nurture”
Star Formation 201“Nurture”
CorporationsEnvironmentalist
s
Shu, Adams & Lizano 1987
Environmental Impact Statement
• How do processes in each stage impact upon each other? (Sequential star formation, outflows reshaping clouds…)
• How long do “stages” last and how are they mixed? (Big cloud--“Starless” Core--Outflow--Planet Formation--Clearing)
• What is the time-history of star production in a “cloud”? Are all the stars formed still “there”?
What’s the right “environmentalist”
approach?Gather a sample where you can statistically
understand:
Observing Biases
Temporal Behavior
Regional Variations
The Environmentalist’s Toolkit
Optical imaging Extinction, reddening dust grain sizes, dust column density
distributionShocked gas (e.g. HH jets)
Near-infrared imaging Same as optical, plus reveals deeply “embedded” young sources
(+ disks)
X-ray Imaging and Spectroscopy Reveals “embedded” sources & identifies sources of bipolar &
spherical outflows
Thermal dust imaging Cold dust “glows” at far-IR and sub-mm wavelengthsdust grain
sizes, dust temperature, plus disk characteristics
Molecular and atomic spectral-line mapping Gives gas density, temperature & velocity distribution
MHD Simulations
2MASS/NICER Extinction Map of Orion
Un(coordinated) Molecular-Probe Line,
Extinction and Thermal Emission Observations
5:41:0040 20 40 42:00
2:00
55
50
05
10
15
20
25
30
R.A. (2000)
1 pc
SCUBA
5:40:003041:003042:00
2:00
1:50
10
20
30
40
R.A. (2000)
1 pc
SCUBA
Molecular Line Map
Nagahama et al. 1998 13CO (1-0) Survey
Lombardi & Alves 2001Johnstone et al. 2001 Johnstone et al. 2001
COMPLETEThe COordinated Molecular Probe Line Extinction Thermal Emission Survey}
The Value of Coordination: B68
C18ODust EmissionOptical Image
NICER Extinction Map
Radial Density Profile, with Critical
Bonnor-Ebert Sphere Fit
Coordinated Molecular-Probe Line, Extinction & Thermal Emission Observations of Barnard 68
This figure highlights the work of Senior Collaborator João Alves and his collaborators. The top left panel shows a deep VLT image (Alves, Lada & Lada 2001). The middle top panel shows the 850 m continuum emission (Visser, Richer & Chandler 2001) from the dust causing the extinction seen optically. The top right panel highlights the extreme depletion seen at high extinctions in C18O emission (Lada et al. 2001). The inset on the bottom right panel shows the extinction map derived from applying the NICER method applied to NTT near-infrared observations of the most extinguished portion of B68. The graph in the bottom right panel shows the incredible radial-density profile derived from the NICER extinction map (Alves, Lada & Lada 2001). Notice that the fit to this profile shows the inner portion of B68 to be essentially a perfect critical Bonner-Ebert sphere
COMPLETE, Part 1
Observations:2003-- Mid- and Far-IR SIRTF Legacy Observations: dust temperature and column density maps ~5 degrees mapped with ~15" resolution (at 70 m)
2002-- NICER/2MASS Extinction Mapping: dust column density maps ~5 degrees mapped with ~5' resolution
2003-- SCUBA Observations: dust column density maps, finds all "cold" source ~20" resolution on all AV>2”
2002-- FCRAO/SEQUOIA 13CO and 13CO Observations: gas temperature, density and velocity information ~40" resolution on all AV>1
Science:– Combined Thermal Emission data: dust spectral-energy distributions, giving emissivity, Tdust and Ndust
– Extinction/Thermal Emission inter-comparison: unprecedented constraints on dust properties and cloud distances, in addition to high-dynamic range Ndust map
– Spectral-line/Ndust Comparisons Systematic censes of inflow, outflow & turbulent motions enabled
– CO maps in conjunction with SIRTF point sources will comprise YSO outflow census
5 degrees (~tens of pc)
SIRTF Legacy Coverage of Perseus
>10-degree scale Near-IR Extinction, Molecular Line and
Dust Emission Surveys of Perseus, Ophiuchus
& Serpens
Is this Really Possible Now?
10-4
10-3
10-2
10-1
100
101
102
103
Time (hours)
20152010200520001995199019851980
Year
1 Hour
1 Minute
1 Day
1 Second
1 Week
SCUBA-2
SEQUOIA+
NICER/8-m
NICER/SIRTFNICER/2MASS
AV~5 mag, Resolution~1'
AV~30 mag, Resolution~10"
13CO Spectra for 32 Positions in a Dark Cloud (S/N~3)
Sub-mm Map of a Dense Core at 450 and 850 m
1 day for a 13CO map then
1 minute for a 13CO map now
Smoke Signals:
COMPLETE’s Ophiuchus
0.5 x 1051 erg SNinto 105 cm-3
2 pc in 200,000 yr T=38K
vexp=1.7 km s-1
HeatedDustRing
Regionknownas
“-OphCluster”
Re-calibrated IRAS Dust Column Density Re-Calibrated IRAS Dust Temperature
ROSAT PSPC
In each panel where it is sho n, the white ring shows a 2 pc circle,corresponding to the size and shape of the heated ring apparent in the IRAS
Temperature Map.
ROSAT Pointed Observation
Real -OphCluster
inside newlydiscoveredheated ring
1RXS J162554.5-233037
The star-Ophand
RXJ1625.5-2326
Goodman, Gaensler, Wolk & Schnee 2003
Perseus in (Coldish) Molecular
Gas
QuickTime™ and aTIFF (Uncompressed) decompressorare needed to see this picture.
Map of 1200 13CO Spectra from Bachiller & Cernicharo 1986 (made with Bordeaux 2.5-m, Beam Area = 31 x FCRAO)
COMPLETE/FCRAO noise is twice as low, and velocity resolution is 6 x higher
Perseus in (Warmish)
Dust 2 x 1051 erg SN
into 104 cm-3
5 pc in 1 MyrT=30K
vexp=1.5 km s-1
QuickTime™ and aTIFF (LZW) decompressorare needed to see this picture.
COMPLETE Perseus
IRAS + FCRAO
(73,000 13CO Spectra, see Scott
Schnee!)
Perseus
QuickTime™ and aTIFF (LZW) decompressorare needed to see this picture.QuickTime™ and aTIFF (LZW) decompressorare needed to see this picture.
Total Dust Column (0 to 15 mag AV) (Based on 60/100 microns)
Dust Temperature (25 to 45 K)(Based on 60/100 microns)
Hot Source in a Warm Shell
QuickTime™ and aTIFF (LZW) decompressorare needed to see this picture.QuickTime™ and aTIFF (LZW) decompressorare needed to see this picture.+ =
Column Density Temperatur
e
COMPLETE, Part 2
(2003-5)
Observations, using target list generated from Part 1:NICER/8-m/IR camera Observations: best density profiles for dust associated with "cores". ~10" resolution FCRAO + IRAM N2H+ Observations: gas temperature, density and velocity information for "cores” ~15" resolution
Science:Multiplicity/fragmentation studies
Detailed modeling of pressure structure on <0.3 pc scalesSearches for the "loss" of turbulent energy (coherence)
FCRAO N2H+ map with CS spectra superimposed.
(Le
e,
Mye
rs &
Ta
falla
20
01
).
<arcminute-scale core maps to get density & velocity structure all the way from >10 pc
to 0.01 pc
On the way to Star Formation 201
Structures in a turbulent, self-gravitating, flows are highly transient
Outflows are episodic
Young stars can move rapidly
Energetically significant spherical outflows (e.g. SNe, winds) are common in star-forming
regions
“COMPLETE” Star Formation c. 2005
Statistical Evaluation of Outflows’ RoleEvaluation of Constructive/Destructive Role of
Explosions/Winds
Tracking down progeny (includes USNO-B
work)
COMPLETE
The COordinated Molecular Probe Line Extinction Thermal Emission Survey Alyssa A. Goodman, Principal Investigator (CfA)
João Alves (ESA, Germany)Héctor Arce (Caltech)
Paola Caselli (Arcetri, Italy)James DiFrancesco (HIA, Canada)
Mark Heyer (UMASS/FCRAO)Di Li (CfA)
Doug Johnstone (HIA, Canada)Naomi Ridge (UMASS/FCRAOCfA)Scott Schnee (CfA, PhD student)
Mario Tafalla (OAS, Spain)Tom Wilson (MPIfR)
Extra Slides
COMPLETE: JCMT/SCUBA>10 mag AV
2468
Perseus
Ophiuchus
10 pc
10 pc
Johnstone, Goodman & the COMPLETE team, SCUBA
2003(?!)
~100 hours at SCUBA
“Steep” Mass-Velocity Relations
HH300 (Arce & Goodman 2001a)
• Slope steepens when corrections made– Previously unaccounted-
for mass at low velocities
• Slope often (much) steeper than “canonical” -2
• Seems burstier sources have steeper slopes?
-3
-8
-4
-8M
ass
/Velo
city
Velocity
How much gas will be pulled along for the ride?
Goodman & Arce 2002
Just how fast is PV
Ceph going?
1.5
1.0
0.5
0.0
-0.5
Inte
nsit
y
400350300250200150100
"Velocity"
Observed Spectrum
Telescope Spectrometer
All thanks to Doppler
Velocity from Spectroscopy
Radio Spectral-line Observations of Interstellar Clouds Spectral Line Observations
Alves, Lada & Lada 1999
Radio Spectral-Line Survey
Radio Spectral-line Observations of Interstellar Clouds
Molecular or Dark Clouds
"Cores" and Outflows
Star Formation 101
Jets and Disks
Extrasolar System
1 p
c
Molecular or Dark Clouds
"Cores" and Outflows
Star Formation 101
Jets and Disks
Extrasolar System
1 p
c
Cores: Islands of Calm in a Turbulent Sea?
"Rolling Waves" by KanO Tsunenobu © The Idemitsu Museum of Arts.
Islands of Calm in a Turbulent Sea
Goodman, Barranco, Wilner & Heyer 1998
Islands (a.k.a. Dense Cores)
Berkeley Astrophysical Fluid Dynamics Grouphttp://astron.berkeley.edu/~cmckee/bafd/results.html Barranco & Goodman 1998
AMR Simulation
Simulated NH3 Map
Goodman, Barranco, Wilner & Heyer 1998
Observed ‘Starting’ Cores: 0.1 pc Islands of (Relative) Calm
2
3
4
5
6
7
8
9
1
v [
km s-1
]
3 4 5 6 7 8 91
2
TA [K]
TMC-1C, OH 1667 MHz
v=(0.67±0.02)TA-0.6±0.1
2
3
4
5
6
7
8
9
1
v
intr
insi
c[k
m s
-1]
6 7 8 90.1
2 3 4 5 6 7 8 91
TA [K]
TMC-1C, NH3 (1, 1)
vintrinsic=(0.25±0.02)T A-0.10±0.05
“Coherent Core”“Dark Cloud”
Size Scale
Velo
city
Dis
pers
ion
Cores = Order from Chaos
Order; N~R0.9
~0.1 pc(in Taurus)
Chaos; N~R0.1
Molecular or Dark Clouds
"Cores" and Outflows
Star Formation 101
Jets and Disks
Extrasolar System
1 p
c
…and the famous “1RXS J162554.5-233037” is right in the Middle !?
2 pc
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