CARMA Large Area Starformation Surve Y v Completing

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CARMA Large Area Star-formation Surve. Y v Completing observations of 5 regions of 120

CARMA Large Area Star-formation Surve. Y v Completing observations of 5 regions of 120 -200 square arcminutes with 7” angular resolution in the J=1 -0 transitions of HCO+, HCN, and N 2 H+ v Regions are in the Perseus and Serpens molecular clouds – covered by the c 2 d Spitzer Legacy project which characterized the young stellar population v Using CARMA to get interferometric and single-dish data to make maps of the full emission v Completed last week: 600 hours total array time

Approximate CARMA mapping areas c p ~3. 5 NGC 1333 High-Activity. 5 pc Barnard

Approximate CARMA mapping areas c p ~3. 5 NGC 1333 High-Activity. 5 pc Barnard 1 Moderate-Activity ~5 ~100 sq. arcmin. ~150 sq. arcmin. (focus of this paper) Composite Herschel 250, 350, 500 μm view L 1451 Low-Activity ~150 sq. arcmin

NGC 1333 SVS -13 Region NHCN Emission HCO+ Emission 2 H+Emission Velocity Field

NGC 1333 SVS -13 Region NHCN Emission HCO+ Emission 2 H+Emission Velocity Field

NGC 1333 SVS-13 Herschel 350 microns versus N 2 H+ emission tracks the structure

NGC 1333 SVS-13 Herschel 350 microns versus N 2 H+ emission tracks the structure in the long wavelength continuum…. The bright region to the northeast is a heated area associated with a reflection nebula. N 2 H+ traces gas >105 per cc and give velocity information.

Beam size in above three maps Provides resolution to study individual objects in the

Beam size in above three maps Provides resolution to study individual objects in the context of the large scale cloud.

Perseus B 1 Region

Perseus B 1 Region

main core N 2 H+ Herschel 250 μm central filaments southern clumps HCN HCO+

main core N 2 H+ Herschel 250 μm central filaments southern clumps HCN HCO+

Object Identification Methods Cloudprops (best for sparse fields) vs. Dendrograms (best for dense/blended fields)

Object Identification Methods Cloudprops (best for sparse fields) vs. Dendrograms (best for dense/blended fields) Molecular Cloud structure is mostly hierarchical … dendrograms avoid small-scale segmentation and naturally capture large-scales in addition to the small-scales

Capturing Large and Small Scales with Dendrogram Approach Moment Zero Maps of Leaves and

Capturing Large and Small Scales with Dendrogram Approach Moment Zero Maps of Leaves and Branches 33 12 IRAS 2 region of NGC 1333 51 12 42 11 55 59 How do largerscale gas structures compare to smaller-scale structures? 55 11 33 42 51 59 Leaf Branch Facilitates an investigation of the turbulent properties of dense gas at different scales in a way that clumpfind-like segmentation would not allow

Results: Non-Binary Dendrogram of NGC 1333 N 2 H+ (1 -0) Integrated Intensity Maps

Results: Non-Binary Dendrogram of NGC 1333 N 2 H+ (1 -0) Integrated Intensity Maps 33 12 42 55 11 59 51 We evaluated the size and kinematics of each identified gas structure How do largerscale gas structures compare to smaller-scale structures? 0. 04 pc Turbulence … across different spatial scales within a single cloud … across different clouds at different stages of evolution?

Results: Non-Binary Dendrogram of NGC 1333 N 2 H+ (1 -0) Fitted Line Dispersion

Results: Non-Binary Dendrogram of NGC 1333 N 2 H+ (1 -0) Fitted Line Dispersion Maps 33 12 42 55 11 59 51 We evaluated the size and kinematics of each identified gas structure How do largerscale gas structures compare to smaller-scale structures? Turbulence … across different spatial scales within a single cloud … across different clouds at different stages of evolution?

Results: Line Dispersion vs. Size in NGC 1333 Gas Structures - - H 2

Results: Line Dispersion vs. Size in NGC 1333 Gas Structures - - H 2 thermal dispersion N 2 H+ thermal dispersion … at 11 K and 25 K Capturing mean internal turbulence

Results: Non-Binary Dendrogram Structure of Barnard 1 N 2 H+ (1 -0) black =

Results: Non-Binary Dendrogram Structure of Barnard 1 N 2 H+ (1 -0) black = nearby protostellar outflows red = further from outflow activity Spitzer IRAC + N 2 H+ outline

Results: Cross-Cloud Comparison Barnard 1 - - H 2 thermal dispersion N 2 H+

Results: Cross-Cloud Comparison Barnard 1 - - H 2 thermal dispersion N 2 H+ thermal dispersion … at 9 K and 12 K vs. NGC 1333 - - H 2 thermal dispersion N 2 H+ thermal dispersion … at 11 K and 25 K

Results: Cross-Cloud Comparison Barnard 1 - - H 2 thermal dispersion N 2 H+

Results: Cross-Cloud Comparison Barnard 1 - - H 2 thermal dispersion N 2 H+ thermal dispersion … at 9 K and 12 K vs. NGC 1333 - - H 2 thermal dispersion N 2 H+ thermal dispersion … at 11 K and 25 K N 2 H+ moment 0 HCO+ outflows § Observe supersonic turbulence at ~0. 01 – 0. 5 pc scales near active young stars not an outflow § Indication that outflows are an important turbulent driver of the dense gas at these scales

Results: Cross-Cloud Comparison Barnard 1 - - H 2 thermal dispersion N 2 H+

Results: Cross-Cloud Comparison Barnard 1 - - H 2 thermal dispersion N 2 H+ thermal dispersion … at 9 K and 12 K not an outflow vs. NGC 1333 - - H 2 thermal dispersion N 2 H+ thermal dispersion … at 11 K and 25 K § Observe subsonic turbulence in filamentary regions yet to form young, active stars § … expected if these dense gas filaments formed from supersonic turbulence § Next step to probe even larger scales and make connection to lower density gas

Summary • Wealth of kinematics on ~1000 s of AU size scale– fully sampled

Summary • Wealth of kinematics on ~1000 s of AU size scale– fully sampled spatial scales • Dendrograms used to decompose dense gas emission and explore kinematics of structures in CLASSy clouds • Compared turbulent linewidths of NGC 1333 and B 1 gas structures: • Star formation feedback correlates with supersonic turbulence at the ~0. 01 – 0. 5 pc scale • B 1 filament is a great region to probe turbulence driven star formation theories

Smaller Scale Magnetic Field Simultaneously observed CO outflow Hull et al. 2013

Smaller Scale Magnetic Field Simultaneously observed CO outflow Hull et al. 2013

Smaller Scale Magnetic Field Inferred magnetic fields are more consistent with random or antialigned

Smaller Scale Magnetic Field Inferred magnetic fields are more consistent with random or antialigned with the outflow axis. Maybe good news for young disks (Vorobyov 2010, Joos et al. 2012, Li et al. 2013) Hull et al. 2013

Disks? What about magnetic braking? Hull et al. 2013 TADPOL results for L 1527

Disks? What about magnetic braking? Hull et al. 2013 TADPOL results for L 1527 and VLA 1623– coupled with no disk detection of L 1157— interesting trend