Chaos

Revealing Order? ~0.5 pc

Order from Chaos: Star Formation in a Dynamic Interstellar Medium Alyssa A. Goodman Harvard-Smithsonian Center for Astrophysics (on sabbatical at Yale Astronomy Department 2001/2) WIYN Image: T.A. Rector (NOAO/AURA/NSF) and Hubble Heritage Team (STScI/AURA/NASA)

Order

WIYN Image: T.A. Rector, B. Wolpa and G. Jacoby (NOAO/AURA/NSF) and Hubble Heritage Team (STScI/AURA/NASA) Chaos

Molecular or Dark Clouds "Cores" and Outflows “Order” Jets and Disks Extrasolar System 1 pc

Outflows Magnetohydrodynamic Waves Thermal Motions MHD Turbulence Inward Motions SNe/GRB H II Regions Chaos

Order in a Sea of Chaos "Rolling Waves" by KanO Tsunenobu © The Idemitsu Museum of Arts.

Evidence for Order in a Sea of Chaos Goodman, Barranco, Wilner & Heyer 1998 “Coherent Core”“Dark Cloud” Size Scale Velocity Dispersion

Evidence for Order in a Sea of Chaos Goodman, Barranco, Wilner & Heyer 1998 OrderChaos Size Scale Velocity Dispersion

Order in a Sea of Chaos "Rolling Waves" by KanO Tsunenobu © The Idemitsu Museum of Arts.

Ancient Historical Record (c. 1993) Order; N~R 0.9 ~0.1 pc (in Taurus) Chaos; N~R 0.1

Order & Chaos What Causes Order? What Causes Chaos?

Order Causes IOTW: What sets the scale for the “Transition to Coherence?” Probably ~ inner scale of magnetized turbulence (often ~0.1 pc) see Eve, Jim; Larson 1995; Goodman et al. 1998; Goodman et al Effects On Cores: Mass, angular velocity, shape, ionization fraction On Stars: Multiplicity This is not the topic for today…

Chaos Quantifying Properties (briefly) Origins (role of outflows) How much does it matter? (question for the future)

Mapping Chaos Dust Emission  N, T dust Extinction  N, dust sizes Molecular Lines  n, T gas, N, v,  v, x i Molecular Line Map Nagahama et al CO (1-0) Survey Lombardi & Alves 2001Johnstone et al. 2001

Quantifying the Properties of Chaos “The Spectral Correlation Function and other ‘sharp’ tools can be used to compare real and simulated spectral line data cubes.” Simulations can map these tools’ product onto physics.

MHD Simulations as an Interpretive Tool Stone, Gammie & Ostriker 1999 Driven Turbulence; M  K; no gravity Colors: log density Computational volume: Dark blue lines: B-field Red : isosurface of passive contaminant after saturation  =0.01  =1  T /10 K  n H 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 Spectral Line Maps

Comparison of Real & Simulated Spectral-Line Maps Falloff of Correlation with Scale Magnitude of Spectral Correlation at 1 pc Padoan & Goodman 2002 “Reality” Scaled “Superalfvenic” Models “Stochastic” Models “Equipartition” Models

Comparison of Real & Simulated Spectral-Line Maps Results so far show: –Driven turbulence gives a approximation to real ISM (see Padoan & Goodman 2002). Still for the future: “Customized” simulation-to-reality comparisons e.g. Do the number of outflows observed in a region effect the observed Mach number there, and does a simulation with that Mach number match that observed cloud well? Do the details of the forcing matter? What happens if detailed outflow simulations are included in more global simulations? Is the “reality match” improved in any way?

The Chaos that is Outflows 1.YSO outflows are highly episodic. 2.Much momentum and energy is deposited in the cloud (~10 44 to erg, comparable or greater than cloud K.E.)--capable of maintaining some degree of chaos. 3.Some cloud features are all outflow. 4.Powering source of (some) outflows may move rapidly through ISM. See collected thesis papers of H. Arce. (Arce & Goodman 2001a,b,c,d; Goodman & Arce 2002).

Redshifted lobe Blueshifted lobe Velocity Intensity Velocity Intensity Outflow Maps

“Typical”(?!) Outflows See references in H. Arce’s Thesis 2001

L1448 Bachiller et al B5 Yu Billawala & Bally 1999 Lada & Fich 1996 Bachiller, Tafalla & Cernicharo 1994 “1. YSO Outflows are Highly Episodic”

Outflow Episodes Figure from Arce & Goodman 2001 HH300 NGC2264

Numerical Simulation of Steady Jet PV diagrams for the shell material at three inclinations cut along the outflow axis for the steady jet simulation; i is the inclination of the outflow to the plane of the sky. Solid lines are calculated using the mean velocity of the shell material. Dashed lines are calculated using the velocity of the newly swept-up material. Dotted lines indicate the zero velocity. (Lee, Stone, Ostiker & Mundy 2001)

A Good Guess about Episodicity

e.g. HH300

Arce & Goodman 2001b Reipurth et al Episodicity on Many Scales Plus “axis wandering”!

B5 Yu, Billawala, Bally, 1999 Mass-Velocity Relations can be very steep, especially in “bursty- looking” sources…

“Steep” M-v Relations HH300 (Arce & Goodman 2001a) Slope steepens when  corrections made –Previously unaccounted-for mass at low velocities Slope often (much) steeper than -2 Seems burstier sources have steeper slopes?

Numerical Simulation of Bow- Shock Jet MV relationships at three inclinations for the steady jet simulation. Both the redshifted (open squares) and blueshifted (filled squares) masses are shown. The dashed lines are the fits to the redshifted mass with a power-law MV relationship, where the power-law index,, is indicated at the upper right-hand corner in each panel. The solid line at i = 0° is calculated from the ballistic bow shock model.

Mass-Velocity Relations in Episodic Outflows: Steep Slopes result from Summed Bursts Power-law Slope of Sum = -2.7 (arbitrarily >2) Slope of Each Outburst = -2 as in Matzner & McKee 2000 Arce & Goodman 2001b

Numerical Simulation of (Sinusoidally-)Pulsed Jet Lee, Stone, Ostiker & Mundy 2001

“2. Much momentum and energy is deposited in the cloud (~10 44 to erg, comparable or greater than cloud K.E.).” BUT: Is there a “typical” amount? H. Arce’s Thesis 2001

“3. Some cloud features are all outflow. That’s how much gas is shoved around!” Arce & Goodman 2001b; 2002a

“4. Powering source of (some) outflows may move rapidly through ISM.” Goodman & Arce 2002

“Giant” Herbig-Haro Flow in PV Ceph Reipurth, Bally & Devine pc

PV Ceph: Episodic ejections from precessing or wobbling moving source Implied source motion ~7 km/s (3 mas/year) assuming jet velocity ~100 km/s Goodman & Arce 2002

“4. Powering source of (some) outflows may move rapidly through ISM.” Goodman & Arce 2002

HST WFPC2 Overlay: Padgett et al Arce & Goodman 2002

Goodman & Arce 2002 Trail & Jet

How much gas will be pulled along for the ride? Goodman & Arce 2002

How Many Outflows are There at Once? What is their cumulative effect?

Action of Outflows(?) in NGC 1333 SCUBA 850  m Image shows N dust (Sandell & Knee 2001) Dotted lines show CO outflow orientations (Knee & Sandell 2000)

Chaos Quantifying Properties (briefly) Origins (role of outflows) How much does it matter? (question for the future)

SIRTF’s 1st Plan for Star-Forming Regions The SIRTF Legacy Survey “From Molecular Cores to Planet-Forming Disks” Neal J. Evans, II, Principal Investigator (U. Texas) Lori E. Allen (CfA) Geoffrey A. Blake (Caltech) Paul M. Harvey (U. Texas) David W. Koerner (U. Pennsylvania) Lee G. Mundy (Maryland) Philip C. Myers (CfA) Deborah L. Padgett (SIRTF Science Center) Anneila I. Sargent (Caltech) Karl Stapelfeldt (JPL) Ewine F. van Dishoeck (Leiden)

SIRTF Legacy Survey Perseus Molecular Cloud Complex (one of 5 similar regions to be fully mapped in far-IR by SIRTF Legacy)

SIRTF Legacy Survey MIRAC Coverage 2 degrees ~ 10 pc

Our Plan for the Future: 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 (Berkeley) Doug Johnstone (HIA, Canada) Scott Schnee (CfA) Mario Tafalla (OAS, Spain) Tom Wilson (MPIfR/SMTO)

Un(coordinated) Molecular-Probe Line, Extinction and Thermal Emission Observations Molecular Line Map Nagahama et al CO (1-0) Survey Lombardi & Alves 2001Johnstone et al. 2001

The Value of Coordination C 18 O Dust Emission Optical 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 C 18 O 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

Is this Really Possible Now? 1 day for a 13 CO map then 1 minute for a 13 CO map now

COMPLETE, Part 1 Observations:  Mid- and Far-IR SIRTF Legacy Observations: dust temperature and column density maps ~5 degrees mapped with ~15" resolution (at 70  m)  NICER/2MASS Extinction Mapping: dust column density maps, used as target list in HHT & FCRAO observations + reddening information ~5 degrees mapped with ~5' resolution  HHT Observations: dust column density maps, finds all "cold" source ~20" resolution on all A V >2”  FCRAO/SEQUOIA 13 CO and 13 CO Observations: gas temperature, density and velocity information ~40" resolution on all A V >1 Science:  Combined Thermal Emission (SIRTF/HHT) data: dust spectral-energy distributions, giving emissivity, T dust and N dust  Extinction/Thermal Emission inter-comparison: unprecedented constraints on dust properties and cloud distances, in addition to high-dynamic range N dust map  Spectral-line/N dust Comparisons Systematic censes of inflow, outflow & turbulent motions will be enabled—for regions with independent constraints on their density.  CO maps in conjunction with SIRTF point sources will comprise YSO outflow census 5 degrees (~tens of pc) SIRTF Legacy Coverage of Perseus

COMPLETE, Part 2 Observations, using target list generated from Part 1:  NICER/8-m/IR camera Observations: best density profiles for dust associated with "cores". ~10" resolution  SCUBA Observations: density and temperature profiles for dust associated with "cores" ~10" resolution  FCRAO+ IRAM N 2 H + Observations: gas temperature, density and velocity information for "cores” ~15" resolution Science:  Multiplicity/fragmentation studies  Detailed modeling of pressure structure on <0.3 pc scales  Searches for the "loss" of turbulent energy (coherence) FCRAO N 2 H + map with CS spectra superimposed. (Lee, Myers & Tafalla 2001).

Order from Chaos: Star Formation in a Dynamic Interstellar Medium Alyssa A. Goodman Harvard-Smithsonian Center for Astrophysics (on sabbatical at Yale Astronomy Department 2001/2) WIYN Image: T.A. Rector (NOAO/AURA/NSF) and Hubble Heritage Team (STScI/AURA/NASA)

HH300: Integrated 12 CO(1-0) Outflow on 13 CO line width, with 13 CO spectra