The COMPLETE Survey of Star-Forming Regions: Why, How & When

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Transcript The COMPLETE Survey of Star-Forming Regions: Why, How & When

The COMPLETE Survey of
Star-Forming Regions at Age 2
Alyssa A. Goodman
Harvard-Smithsonian Center for Astrophysics
cfa-www.harvard.edu/~agoodman
The
COordinated
Molecular
Probe
Line
Extinction
Thermal
Emission
Survey
COMPLETE
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/FCRAOCfA)
Scott Schnee (CfA, PhD student)
Mario Tafalla (OAS, Spain)
Tom Wilson (MPIfR)
COMPLETE’s Birthplace:
The 2001 Santa Cruz
Star Formation Workshop
The Lesson of Coordination: B68
Optical
Image
Dust Emission
C18O
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
NICER
Extinction
Map
Radial Density
Profile, with Critical
Bonnor-Ebert
Sphere Fit
Nagahama et al. 1998 13CO (1-0) Survey
Un(coordinated) MolecularProbe Line, Extinction and
Thermal Emission
Observations
Molecular Line
Map
2MASS/NICER Extinction Map of Orion
1:50
50
1 pc
55
2:00
2:00
05
10
10
20
15
1 pc
20
30
25
SCUBA
30
40
5:41:00
20
40
R.A. (2000)
40
42:00
SCUBA
42:00
Johnstone et al. 2001
Lombardi & Alves 2001
30
41:00
R.A. (2000)
30
Johnstone et al. 2001
5:40:00
Bipolar outflows from young stars
+
Stellar winds & photons from older stars
+
Large Explosions (SNe, GRBs)
create, maintain, & destroy molecular clouds
& ultimately determine stellar output vs. time
a.k.a. what
we’d all like
to know
Time is a key dimension
but
spatial statistics remain our best hope
to understand it.
Could we really…?
10
10
Time (hours)
10
10
3
1 day for a
map when
the 3 wise
men were 40
A V~5 mag, Resolution~1'
13CO
2
A V~30 mag, Resolution~10"
13
CO 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
1
0
1 Hour
NICER/8-m
10
1 Week
-1
1 Minute
SEQUOIA+
10
10
-2
1 minute for
the same
13CO map today
-3
SCUBA-2
1 Second
10
NICER/2MASS
-4
1980
1985
1990
1995
NICER/SIRTF
2000
Year
2005
2010
2015
The
COMPLETE
COordinate
d
Molecular
Probe
Line
Extinction
Thermal
Emission
Survey
COMPLETE,
Part 1
Observations:
5 degrees (~tens of
pc)
SIRTF Legacy
Coverage of
Perseus
2003-4-- Mid- and Far-IR SIRTF Legacy Observations: point-source census,
>10-degree scale Near-IR
Extinction, Molecular Line
and
Dust
Emission
Science:
Surveys of Perseus,
Ophiuchus & Serpens, <1
dust temperature and column density maps ~5 degrees mapped with ~15" resolution
(at 70 m)
2002-3-- NICER/2MASS Extinction Mapping: dust column density maps
~5
degrees mapped with ~5' resolution
2003-4-- SCUBA Observations: dust column density maps, finds all "cold"
source ~20" resolution on all AV>2”
2002-4-- FCRAO/SEQUOIA 13CO and 13CO Observations: gas temperature,
density and velocity information ~40" resolution on all AV>1
–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 &
(Lee, Myers & Tafalla 2001).
COMPLE
TE, Part 2
(2003-5)
FCRAO N2H+ map with CS spectra superimposed.
Observations, using target list generated from Part 1:
<arcminute-scale core
maps to get density &
Science:
velocity structure all the
way from >10 pc to 0.01
pc
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
Multiplicity/fragmentation studies
Detailed modeling of pressure structure on <0.3 pc scales
Searches for the "loss" of turbulent energy (coherence)
Time Dependences we did not worry about
when David, Chris & Frank were 50
1. Structures in a turbulent, self-gravitating,
flow are highly transient
2. Outflows are episodic
3. Young stars can move rapidly
4. Energetically significant spherical
outflows (e.g. SNe, winds) are common in
star-forming regions
5. (Aging)
1. Structures
are Highly
Transient
•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 L, G
•movie=1.4 free-fall times
Bate, Bonnell & Bromm
2002
QuickTime™ and a Cinepak decompressor are needed to see this picture.
B5
Yu, Billawala & Bally 1999
Bachiller et al. 1990
L1448
Lada & Fich 1996
Bachiller, Tafalla & Cernicharo 1994
2. YSO Outflows
are Highly Episodic
Outflow Episodes:Position-Velocity Diagrams
NGC2264
Figure from Arce & Goodman 2001
HH300
3. Powering source of (some) outflows may
zoom through ISM
PV Ceph is
moving at
~10 km s-1
1 pc
Goodman & Arce 2003
4x10
Moving Source & Slowing Knots
18
500x10
70
15
60
Star
Distance along x-direction (cm)
y knot pos itions (cm)
400
2
Star-Knot
Difference
(%)
50
300
Star-Knot
Difference
40
30
200
1
Star-Knot Difference/Star Offset (Percent)
3
20
Knot
100
Initial jet 250 km s1; star motion 10
km s-1
0
-4x10
17
-2
10
0
0
5
10
15x10
3
0
0
x knot posns. w.r.t. star "now" (cm)
Elapsed Time since Burst (Years)
Goodman & Arce 2003
4x10
Dynamical Time Estimates off by x10
18
10
9
8
3
"Dynamical Time"/Elapsed Time
y knot pos itions (cm)
7
2
6
5
For an HH object at 1 pc from
source,
dynamical time calculation
overestimates age by factor of
~ten.
4
3
2
1
1
0.0
0.5
1.0
1.5
2.0
2.5
3.0x10
18
Distance of Knot from Source (cm)
0
-4x10
17
-2
0
x knot posns. w.r.t. star "now" (cm)
Goodman & Arce 2003
(All the) Maps of “Giant” Outflows, c. 2002
See references in H. Arce’s Thesis 2001
Time Dependences we did not worry about
when David, Chris & Frank were 40
1. Structures in a turbulent, self-gravitating,
flow are highly transient
2. Outflows are episodic
3. Young stars can move rapidly
4. Energetically significant spherical
outflows (e.g. SNe, winds) are common in
star-forming regions
COMPLETE
Discovery of a Heated Dust Ring in Ophiuchus
2 pc
Goodman, Li & Schnee 200
Re-calibrated IRAS Dust Column Density
Re-Calibrated IRAS Dust Temperature
Heated
Dust
Ring
Smoke Signals
from
Ophiuchus
0.5 x 1051 erg SN
into 105 cm-3
2 pc in 200,000 yr
T=38K
vexp=1.7 km s-1
ROSAT PSPC
The star r-Oph
and
RXJ1625.52326
Region
known
as
“r-Oph
Cluster”
Goodman, Gaensler,
Wolk & Schnee 2003
ROSAT Pointed Observation
Real r-Oph
Cluster
inside newly
discovered
heated ring
1RXS J162554.5-233037
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
Ionized Gas in the Ophiuchus Smoke Shell
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SII
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SHASSA Data courtesy of John Gaustad
Ha
COMPLETE
Warm Dust Emission shows
Great
Bubble in
Perseus
2 x 1051 erg SN
into 104 cm-3
5 pc in 1 Myr
T=30K
vexp=1.5 km s-1
Perseus in
(Coldish)
Molecular
Gas
QuickTime™ and a TIFF (Uncompressed) decompressor are 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
COMPLET
E
Perseus
IRAS +
FCRAO
(73,000 13CO Spectra)
Perseus
Total Dust Column (0 to 15 mag AV)
(Based on 60/100 microns)
Dust Temperature (25 to 45 K)
(Based on 60/100 microns)
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QuickTime™ and a TIFF (LZW) decompressor are needed to see this picture.
Hot Source in a Warm Shell
Column
Density
Temperature
+
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and
TIFF
(LZW)
decompressor are needed to see this picture.
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are needed
toasee
this
picture.
=
The action of
multiple
bipolar
outflows in
NGC 1333?
SCUBA 850 mm Image
shows Ndust (Sandell & Knee
2001)
Dotted lines show CO
outflow orientations (Knee &
Sandell 2000)
>10 mag AV
8
6
4
2
JCMT/SCUBA
COMPLETE
~100 hours at
SCUBA
10 pc
10 pc
NGC1333
Map
Ophiuchus
= in SCUBA archive
= observed Spring ‘03
Perseus
All at >5 mag, by 2004
My Near-Term “COMPLETE”
Agenda
Statistical Evaluation of Outflows’ Role
Evaluation of Constructive/Destructive Role of
Explosions/Winds
Tracking down progeny
“Early” Times
“Later” Times
The
COordinated
Molecular
Probe
Line
Extinction
Thermal
Emission
Survey
COMPLETE
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/FCRAOCfA)
Scott Schnee (CfA, PhD student)
Mario Tafalla (OAS, Spain)
Tom Wilson (MPIfR)
Questions up for Grabs
•
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?
•
What is the time-history of star production in a
“cloud”? Are all the stars formed still “there”?
(Big cloud--“Starless” Core--Outflow--Planet
Formation--Clearing)
Extra Slides
Nature
Shu, Adams & Lizano 1987
Nurture
Corporations
Shu, Adams & Lizano 1987
Environmentalists
Theory
Shu, Adams & Lizano 1987
Observation
• Slope steepens when t
corrections made
– Previously unaccounted-for
mass at low velocities
• Slope often (much) steeper
than “canonical” -2
• Seems burstier sources have
steeper slopes?
Mass/Velocity
“Steep” Mass-Velocity
Relations
-3
-8
Velocity
-4
-8
HH300 (Arce & Goodman 2001a)
How much gas will be pulled along for the ride?
Goodman & Arce 2002
Perseus in
(Coldish)
Molecular
Gas
Cores = Order from Chaos
~0.1 pc
(in Taurus)
Order; N~R0.9
Chaos; N~R0.1