Debris DiskDebris DiskDetecting Debris Disks

Using Adaptive Optics

Nasim NadersereshtUC Berkeley

OutlineOutline• Formation of the star• Formation of planets• Formation of the debris disk• The importance of studying

debris disks• Debris disk Experiment –

Sensitivity Limit

The Formation of a Star

Debris DisksDebris DisksEdge-on Face-on

Anatomy of Face-on Debris Disk

ExperimentExperiment•Finding Sensitivity Limit for

the planet/debris disk– Probability of sighting a

planet/debris disk•Make an artificial planet/debris disk• Inserting the planet/disk to data•Change the brightness of the

planet/disk

Image captured by Paul Kales with Keck telescope in Hawaii 2004

HD191849

b = x

b = 2x

b = 4x

b = 5x

b = 10x

b = 15x

b = 20x

Planet

b = x b = 2x b = 4x

b = 10x b = 15x b = 20x

Change in Brightness (b)

b = x

b = 2x

b = 8x

b = 10x

b = 20x

b = 30x

b = 40x

Finding the Probability

b = 8x b = 10x b = 12x

b = 14x b = 16x b = 18x

Level of Brightness on Noise vs. Black regions

k = x

k = brightness

Debris disk inserted to the data

k = 2x

k = 3x

k = 4x

k = 5x

k = 6x

k = x

k = 4x

k = 2x k = 3x

k = 6xk = 5x

Conclusion• fdd = (1/x)fstar• fstar = 1.89 e08 DN/sec• fdd= k ∫ r(-a) dr = k* r(-a)/(1-a) │

[rmin(1-a) - rmax

(1-a)]*(k/1-a)

• fdd=32600 ± 19600 DN/sec• 1/x=1.72 e-4 ± 1.04 e-4

rmax

rmin rmin

rmax

AcknowledgementsAcknowledgementsJames Graham, Advisor

Michael Fitzgerald, Supervisor

Lisa Hunter, Associate Director, Education and Human Resources

Malika Moutawakkil Bell, Education Coordinator

Hilary O’Bryan, Program Coordinator

Kalas, Paul. “Circumstellar Disk Learning Site,” (2005). Retrieved July 3rd, 2006, from http://astro.berkeley.edu/~kalas/disksite/learnframes.htm.

Funding Provided by NSF and the Center for Adaptive Optics Grant No. AST-9876783