Massive Star Formation: The Role of Disks Cassandra Fallscheer In collaboration with: Henrik Beuther, Eric Keto, Jürgen Sauter, TK Sridharan, Sebastian Wolf, Qizhou Zhang Great Barriers in Massive Star Formation September 16, 2010

Three sources in an evolutionary sequence Infrared Observations Infrared Observations C 18 O line width C 18 O line width Decrease in size of possible disk observations Decrease in size of possible disk observations Amplitude (Jy/beam) IRDC IRAS IRAS

Three Case Studies IRDC IRDC IRAS IRAS IRAS IRAS AGEAGE

IRDC : Infrared Dark Cloud Distance~3.7 kpc Distance~3.7 kpc Beuther, Sridharan & Saito color Spitzer image with 3mm cont. contours 1.2 mm single dish contours, 8 micron MSX image 1 pc

IRDC : Infrared Dark Cloud Distance~3.7 kpc Distance~3.7 kpc Beuther, Sridharan & Saito color Spitzer image with 3mm cont. contours 1.2 mm single dish contours, 8 micron MSX image 1 pc Rolf Kuiper’s talk tomorrow Fallscheer et al. 2009, A&A, 504, 127 outflow CH 3 OH Velocity Moment Map

Infall model Infall model Density distribution Velocity distribution Input quantities: 50 M sun 1.5 km/s observed at AU Model collapse of an initially rotating structure Model includes gravity and conserves angular momentum 10 4 AU

Three Case Studies IRDC IRDC IRAS IRAS IRAS IRAS AGEAGE

The high mass protostellar object IRAS kpc away 3.0 kpc away Davis et al. 2004, A&A, 425, AU

Modeling with MC3D Low Mass: Butterfly Star High mass: IRAS α, radial density parameter β, disk flaring parameter M dust M  2.2 M  R out, radius where density=0 300 AU 5000 AU R *, T *, L * 2 R , 4000 K, 0.92 L  6.4 R , K, L  Observations +/- 1σ Model ____ ……… - - Fallscheer et al. 2010, submitted

Predictions for the Future Predictions for ALMA, JWST, E-ELT Predictions for ALMA, JWST, E-ELT Mid-infrared to millimeter wavelengths Mid-infrared to millimeter wavelengths

Three Case Studies IRDC IRDC IRAS IRAS IRAS IRAS AGEAGE

Hot Molecular Core: IRAS L bol ~32,000 L sun (O9.5) L bol ~32,000 L sun (O9.5) D~3.9 kpc D~3.9 kpc Moment maps do not reveal evidence for rotation Moment maps do not reveal evidence for rotation

Points to remember Three sources in an evolutionary sequence may be used to deduce a scenario for disk evolution Three sources in an evolutionary sequence may be used to deduce a scenario for disk evolution Elongated disk-like features decrease with evolutionary stage Elongated disk-like features decrease with evolutionary stage 20,000 AU velocity structure can be reproduced with a collapsing rotating model…disk possibly in the center 20,000 AU velocity structure can be reproduced with a collapsing rotating model…disk possibly in the center Elongation in the dust continuum modelled with a scaled up version of a low mass disk Elongation in the dust continuum modelled with a scaled up version of a low mass disk

How the parameters affect the SED H 0 =5 H 0 =10 H 0 =15 θ =60° θ =90° M=2.2 M=1.2 Scale height at 100AUInclination Angle Central starDust mass of disk

The importance of short spacings Comparison with and without short spacings Comparison with and without short spacings +=

Where new files come from SED & Radial Brightness profile: run 68 SED & Radial Brightness profile: run 68 SED H_0: seds 61, 59B, 53 SED H_0: seds 61, 59B, 53 SED theta: 67A,67B SED theta: 67A,67B SED mass: 68,67A SED mass: 68,67A Img68.jpg Img68.jpg JWST/E-ELT Figure from Henrik, overlay_cassie.eps JWST/E-ELT Figure from Henrik, overlay_cassie.eps