Fwd: solar-b diffraction

[Ed Deluca <edeluca@cfa.harvard.edu>]

Hi Kano san,

  Below is an answer to your question about the width of the  
aperture, 0.32mm.

  There is no additional masking by the filter frames or aperture stop.

  Paul Reid was at Danbury Optical when the XRT mirror was being
designed and manufactured. He is now at SAO.

Ed

===================================================================
       Dr. Edward E. DeLuca           Smithsonian Astrophysical  
Observatory
       edeluca@cfa.harvard.edu     MS 58
Office 617 496 7725                     60 Garden Street
Fax     617 496 7577                     Cambridge, MA  02138
Cell    508 728 5424                     USA
===================================================================


Begin forwarded message:

> From: Paul Reid <preid@cfa.harvard.edu>
> Date: May 23, 2007 1:08:59 PM EDT
> To: Leon Golub <lgolub@cfa.harvard.edu>, "Peter Cheimets"  
> <pcheimets@cfa.harvard.edu>, edeluca <edeluca@cfa.harvard.edu>
> Cc: "Reid, Paul" <preid@cfa.harvard.edu>
> Subject: solar-b diffraction
>
> Alright, so it's pretty close to linear...
>
> I get 0.32 mm aperture width for the as-built, and an original  
> nominal as 0.64 mm
>
> At 0.56 keV (think that was where EE performance was spec'd) the EE  
> due to diffraction is:
>
>   EE (per cent)		0.32 mm aperture	0.64 mm aperture
> 			diameter (arc-sec)	diameter (arc-sec)
> --------------------------------------------------------------------
>
> 	50			0.761			0.384
>
> 	68			1.125			0.569
>
> 	90			2.016			1.071
> --------------------------------------------------------------------
>
> The first "zero" (real dark ring) in the diffraction pattern occurs  
> at 1.46 and 0.72 arc-sec radius for the 0.32 mm and 0.64 mm  
> apertures, respectively.
>
> Paul
>
> -- 
> Dr. Paul B. Reid
> Harvard-Smithsonian Center for Astrophysics
> 60 Garden St.   M/S 04
> Cambridge, MA 02138
>
> 617-495-7233 (voice)
> 617-495-7356 (fax)