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Project Pages (Stuff currently on my plate - ordered by priority)

• Scrambler Paper
• Gravitationally induced turbulence
• Colliding Flows
• Thermally Unstable clouds
• MHD Clumps
• Mapping Out Cooling Regimes for Shocked Clumps
• The Morphological Impact of Cooling on Turbulence

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Recent Blog Entries

• test  -- Posted on 4 years ago : author Jonathan
• HEDP Experiments  -- Posted on 4 years ago : author Jonathan
• Spitzer Resistivity  -- Posted on 4 years ago : author Jonathan
• HEDP Simulations  -- Posted on 4 years ago : author Jonathan
• Thoughts on time stepping and MHD  -- Posted on 4 years ago : author Jonathan

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Journal Club for March 22

Literature survey:

Klessen Heitsch MacLow 2000

• Collapse can only be prevented with unrealistically short wavelength driving
• Realistic driving ength gives observed core formation rates
• Discuss various dispersion relations for jeans analysis with turbulence
• Reference Bonazzola 1992 which has a critical spectra for support of alpha = 3 (outflow turb?)
• SPH and Lagrangian 3D Hydro Periodic 64 Jeans Masses
• Drive with various scales for 1 crossing time and then switch on self-gravity
• Forcing patterns described in MacLow 1998 and 1999

Heitsch Maclow Klessen 2000

• Similar to above but with MHD
• Density contrasts are lessened because of magnetic pressure
• Flow is organized into sheets - more clustered

Ossenkiof Klessen Heitsch

• Applied delta variance technique to self gravitating turbulence
• Periodic Box
• Density spectra has positive slope when self-gravity is important
• Propose to compare it with dust observations instead of 12CO to have a higher density contrast range
• 256³

Heitsch et al 2005

• Non-gravitating hydro colliding flows with cooling
• NTSI, KH, TI, but no discussion of Richtmeyer-Meshkov instability (Impulsive-accelerating RT instability)
• Look at 'core' properties (though 2D and no SG)

Heitsch et al 2006 "Birth of Molecular Clouds"

• Extended 2005 work to 3D
• no sg and hydro
• sinusoidal interface
• .5 particles/cc
• periodic (open in 2D)

Audit & Hennebelle 2005

• 2D colliding flows

Heitsch et al 2006 "Magnetized Non-Linear thin shell instability -2D"

• 2D MHD using PROTEUS
• Fields weaken or suppress NTSI

Heitsch et al 2006 "Cloud Dispersal in Turbulent Flows"

• no sg- looked at turbulent dispersal of clouds

Heitsch, Stone, and Hartmann 2008 "Effects of Magnetic Field Strencth and Orientation on Molecular Cloud Formation"

• Athena 3D 256³ - no sg - mhd
• Fields are important to resulting structure
• Fields normal to flow favor filamentary structure in collision plane
• Fields perpendicular to flow (ie y ) suppress ntsi along field axis (ky /= 0) and give an extended slab with filaments normal to field

Heitsch, Hartmann, and Burkert "Fragmentation of Shocked Flows: Gravity, Turbulence, and Cooling"

• Theory paper
• Star formation happens soon after MC formation
• Density enhancements are produced along with MC - problem with 'condensation models'
• Nead non-linear density enhancements - faster than gravity
• Discuss TI, GI, NTSI, KHI
• Phase diagrams with lines outlining dominate instabilities
• Dynamical and thermal instabilities dominate on small scales
• Thermal fragmentatation dominates gravitational fragmentation during cloud formation
• TI alone cannot produce jeans unstable clumps… need additional global compression

VazqueszSemadeni 2006

• Velocity perturbations

Inoue and Inutsuka 2012

• Colliding Flows in 3D
• Richtmyer-Meshkov instability
• No dynamical sg
• 1024³