Image: ISAS/JAXA

Christopher StarkUniversity of Maryland

NASA Goddard Space Flight Center

Collisional Grooming:

Including Collisions in (Prohibitively Large)N-body Simulations

Fomalhaut

Kalas et al. 2005

Greaves et al. 1998

Eri

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Schneider et al. 2009

HR 4796A

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Kalas et al. 2008

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

QuickTime™ and aAnimation decompressor

are needed to see this picture.

Fomalhaut

Kalas et al. 2005

Greaves et al. 1998

Eri

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Schneider et al. 2009

HR 4796A

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Velocity Dispersion in a Structured Debris Disk

PR + solarwind drag

Stellargravitational

force

Planetarygravitational

forces Radiation pressure

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Ni = Ni(t=0)

Ni(t=t) = Ni(t=0)e-

Ni(t=2t) = Ni(t=t)e-

Ni(t=3t) = Ni(t=2t)e-

i

i

i

The Collisional Grooming Algorithm

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Iterative Convergence of the Collisional Grooming Algorithm

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Correctness of Solution to the Mass Flux Equation

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Qu

ickTim

e™

and a

TIF

F (

Un

com

pre

ssed)

decom

pre

sso

rare

need

ed t

o s

ee t

his

pic

ture

.Collision Rate in a Resonant Ring Structure

Collision Rate in a Resonant Ring Structure

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

No Collisions More Collisions

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Ni = Ni(t=0)

Ni(t=t) = Ni(t=0)e- i

Fragmentation

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Fragmentation

Fomalhaut

Kalas et al. 2005

Greaves et al. 1998

Eri

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Schneider et al. 2009

HR 4796A

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Distribution of KBOs

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

= 0.6 m

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

= 60 m

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

= 800 m

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Disk-Total Grain Size Distribution

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Summary

• Grain-grain collisions play an important role in determining debris disk morphology, even for disks with optical depths ~10-7

• Collisional grooming allows us to include gravitational resonant dynamics and grain-grain collisions simultaneously & self-consistently

• Algorithm runs post-integration & takes ~1 hour on a single processor