Prof. Mel Ulmer

DEPT OF PHYSICS

&

ASTRONOMY

The Concept:

Intact Electroforming Multilayer Process

Coated Mandrel

Astrophysical Motivation• Hard X-ray Astronomy (20- 100 keV) is rich but:

• Need focusing for improved sensitivity and imaging

• Flexible design of focal length

• Need the best angular resolution possible

resolution 1.5 2.25 3. arc min

45 arc sec resolution 15 22.5 arc sec

Cas A

8.5 x 8.5 arc min

24 x 24 arc sec

1.3 x 1.3 arc min

3.5 x 3.5 arc min

3C 273 Per A

Gal. Cen.

Advantages of IEMP:

• Coat Mandrel => Focal Length, small as 1-2 meters => SMEX is possible • Electroforming offers the best angular resolution (< 10 arc sec) outside custom figuring

• An additional advantage of proccess at NU =

CNx coating (10 nm) smooths & protects

Now the entire process:

Coat mandrel with CNxCoat mandrel with CNx

Coat mandrel with release layerCoat mandrel with release layer

Coat with multilayersCoat with multilayers

Coat with adhesion layersCoat with adhesion layers

ElectroformElectroform

Remove electroformRemove electroform

Remove release layerRemove release layer

Two different Two different orientations about orientations about optical axis, same optical axis, same energyenergy

About 90 deg About 90 deg rotation rotation

Higher EnergyHigher Energy

Conclusion: Excellent Multilayers because:Conclusion: Excellent Multilayers because:

• Same Bragg angles at different Same Bragg angles at different energies, more penetrating versus lessenergies, more penetrating versus less

• Narrow Bragg peaks Narrow Bragg peaks

• One multilayer d-spacing = 5.29 nm fits allOne multilayer d-spacing = 5.29 nm fits all

• Same Bragg angles at different axis rotationsSame Bragg angles at different axis rotations

• All the above plus fits indicate well over 10% All the above plus fits indicate well over 10% efficiency. How high? Perhaps near theoretical efficiency. How high? Perhaps near theoretical = 80% = 80%

30 cm long, 12 cm dia.

2 m focal length Wolter I

With multilayers

First Light

Where do we go from here?Where do we go from here?

• Further analysis of in hand mirror to Further analysis of in hand mirror to cement reflectivity efficiency estimatescement reflectivity efficiency estimates

• Advance to an even better truncated cone Advance to an even better truncated cone mandrelmandrel

• Move to graded d-spacing with new Move to graded d-spacing with new multilayer coating chambermultilayer coating chamber

• Advance to Wolter I mirrors and fly Advance to Wolter I mirrors and fly them!! them!!

Co-Authors: Bob I. Altkorn, Anita Madan, Mike Co-Authors: Bob I. Altkorn, Anita Madan, Mike Graham, and Yong S. ChuGraham, and Yong S. Chu

Helpers, collaborators, etc. : Al Krieger, Dan Helpers, collaborators, etc. : Al Krieger, Dan Parsignault, Derrick Mancini, Matt Steele, Peter Parsignault, Derrick Mancini, Matt Steele, Peter Takcas, Yip-Wah Chung, Jane ChangTakcas, Yip-Wah Chung, Jane Chang

NASA Support: SR&T and NASA Support: SR&T and Con X Con X

www.astro.nwu.edu/astro/faculty/ulmerwww.astro.nwu.edu/astro/faculty/ulmer

The

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