Portrait of a Forming Massive Protocluster: NGC6334 I(N) Todd Hunter (NRAO/North American ALMA Science Center) Collaborators: Crystal Brogan (NRAO) Ken (Taco) Young (CfA) Great Barriers in High Mass Star Formation Townsville, Australia, Sept. 2010

2 The NGC6334 Star Forming Complex Distance ~ 1.7 kpc Nomenclature: FIR sources I..VI radio source A..F SCUBA 850  m dust continuum GLIMPSE 3.6  m 4.5  m 8.0  m I (2000 M  ) I(N) (2800 M  ) 25 ’ = 15 pc NGC 6334 I luminosity 3x10 5 L , I(N) two orders of magnitude less Based on infrared, I(N) speculated to be less evolved than I 1 pc Source I NIR cluster with density of ~1200 pc -3 (Tapia et al. 1996)

Single dish view of molecular lines 3 Examples from Mopra mapping survey (Walsh et al. 2010) N 2 H+ (1-0) CH 3 CN (5-4)

High Resolution Continuum 4 SCUBA 850  m continuum 1.3 mm 6”= 10,000 AU

5 SMA, VLA, Spitzer observations Brogan, Hunter et al. (2009) 6”= 10,000 AU ~1.7” 3.6  m4.5  m24  m SiO(5-4) outflow 1.3 mm Continuum + 44 GHz methanol masers 1.3 mm 7 mm

6 Zooming in on NGC6334 I(N) Brogan, Hunter et al. (2009) 6”= 10,000 AU 1.3 mm 7 mm ~1.7” 1.3 mm 7 mm 0.87 mm

7 protostellar density is ~500 pc -2 VLA Water Maser spectra H 2 O masers show linear vel. gradient 6.7 GHz maser MIPS 24 um

8 Multiple hot cores (and more) SMA6: Curious line-free source  Large and cool? (Hosokawa et al. 2010)

I(N) CH 3 CN Temperatures 9 Some require two velocity and temperature components. T hot =130 K, T B =40 K Size ~ 0.3” = 500 AU Cluster dynamics:  v=5km/s, rms=1.6

CH 3 CN J=12-11 Kinematics 10 K=2 E lower =87 K K=7 E lower =400 K  K=2 is optically thick and avoids continuum peak

CH 3 CN J=12-11 Kinematics at SMA1 11 K=4 (E lower = 168 K)K=7 (E lower = 400 K) If SMA 1b/1d is indeed a binary, SMA 1b is clearly dominant

106 K/Jy at 222GHz; 89 K/Jy at 342 GHz Dust emission at 800 AU resolution 12 SourceIntegrated Flux density (mJy) Brightness T (K) Gas T (K) Warm Gas Mass (M  ) 1b/d , a , , ? ? ? ?1

13 Summary ~800 AU imaging of NGC6334I(N) protocluster reveals: 12 compact sources: protostellar density ~ 500 pc -2 SMA1b = main hot core, CH 3 CN velocity gradient suggests rotation Velocity dispersion of 1.6 km s -1 ; t cross ~8x10 4 years T gas ~ 60 to 150 K, masses at this resolution are a few to few 10s of solar. A range of evolutionary states present ⇨ ALMA will break both barriers by a significant factor ⇨ Early science call in the next few months Two “greatest barriers” to understanding massive star formation:  Angular resolution limit of 0.3”  Sensitivity limit of ~1 mJy continuum

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16 The NGC6334 I Protocluster 6”= 10,000 AU 10,000 AU 3.6 cm continuum (ionized gas) SMA 1.3 mm Continuum Resolution: 0.”8 x 0.” x 700 AU Peak Velocity (km/s) 1.3 mm 3.6 cm CO(2-1) HMPO density is ~10,000 pc -3

17 Food for Thought…. At our current resolution, each dust core could harbor even more kinematicallydistinct multiple protostars which can easily mimic a disk (see for example Brogan et al for CepA-East) Zinnecker & Yorke (2007)