;
; This document describes the HESSI shutter design.  It also includes a full description
; of all materials in the x-ray path starting at the outermost thermal blankets
; around the collimator tube, to the thermal blankets under the collimator, the beryllium
; windows within and outside the cryostat.
;
;From - Tue Jun 29 14:59:18 1999 from Gordon Hurford
;
;Based on UCB's Dummy Shutter drawings (HSIS212 and 214) and Paul's
;e-mail of 22 June, it would appear that:
;
;1. The 'THICK' shutter (nominal .060") refers to shutter 'A' and               defaults to
;OUT on launch and in override mode.
;
;2. The 'THIN'  shutter (nominal .015") refers to shutter 'B' and               defaults to
;IN.
;
;To avoid confusion, I recommend that we label our attenuator disks 
;as A and B accordingly and drop the THIN and THICK designations.
;
;gordon
;
; Here is an email from April 1999 from Paul Turin on the mylar in the X-ray path within the cryostat.

;Richard,
;I think I finally have the correct cryostat blanket info. Blanketing in
;front of the detectors is as following (going in the direction of X-ray
;travel):
;
;Outer shield blankets:
;
;1-mil mylar, VDA 1 side
;1/4-mil mylar, VDA 2 sides
;1/4-mil mylar, VDA 2 sides
;
;1/4-mil mylar, VDA 2 sides
;1/4-mil mylar, VDA 2 sides
;
;1/4-mil mylar, VDA 2 sides
;1-mil mylar, VDA 1 side
;                                                                                  
;Inner shield blanket:
;
;1-mil mylar, VDA 1 side
;8 layers 1/4-mil mylar, VDA 2 sides
;1-mil mylar, VDA 1 side
;
;All netting has cutouts over detectors.
;
;Total material in path = 7.25 mils mylar 
;VDA = Vapor-Deposited Aluminum, Angstroms thick
;
;
;Paul Turin
;Space Sciences Lab
;U.C. Berkeley
;pturin@ssl.berkeley.edu
;
; 7.25 mils mylar = .002192 *  gm/cm2/mil * 7.25 mils of carbon
; 	plus
;		    .001168 * gm/cm2/mil * 7.25  mils of oxygen
; 
; at http://www.filmcapacitors.com/dielect.htm
; we find the density of Polyester(Mylar) given as 1.395
; Using the densities above,
;IDL> print,(.002192+.001168)*1000./2.54     
;      1.32283
; So we are at least close to a standard value. Whew!

; The filter plus blanket transmisson can be calculated in each of the four states by using
; this file and HESSI_FILTERS()
; For a set of energies, <emdges>, in keV greater or equal to 3 keV. And where <file> is the
; full path to this file.
;
; For the case of both shutters open,

; Open_Transmission = hessi_filters(emdges,/shutters,shutter_file=file)

; For the case of shutter B(Thin) closed  and A(Thick) open,

; Thin_B_Transmission = hessi_filters(emdges,/shutters,/thin, shutter_file=file)

; For the case of shutter B(Thin) open and A(Thick) closed,

; Thick_A_Transmission = hessi_filters(emdges,/shutters,/thick, shutter_file=file)

; For the case of shutter B(Thin) closed and A(Thick) closed,

; Thin_B_plus_Thick_A_Transmission = hessi_filters(emdges,/shutters,/thick, shutter_file=file)

;
;The following is the data structure used to describe all of the elements in the X-ray path.
;The thickness units default is 'cm', although 'mils' is most commonly used.
;Presently, only 'mils' is recognized as an alternative to a blank string. 
;The id tag means, 0- fixed in path, 1- part of shutter_10 (Thin/B), 2-part of shutter_01(Thick/A).
;  
;hessi_win = { hessi_win5, fraction:fltarr(5), regions:intarr(5), layers: intarr(2), $
;	thickness: fltarr(2), units:'', z:0, id:0} 

; Define the fractional areas of 4 regions defining the X-ray path cross-section.
; These are the fractional values seen in the lines defining the material in each layer and segment.
;0.850, .050, .0874, 0.012, 0.0006 ;frac1, frac2, frac3, frac4, frac5
0.833207,    0.0841974,    0.0719123,   0.00749464,   0.00318893 ;frac1, frac2, frac3, frac4, frac5 disc9


; Top of imager

;Imager Top Kapton mylar, all regions,  3 or 5  mil mylar, carbon
frac1, frac2, frac3, frac4, frac5, 1 1, 1, 1, 1,       1, 1,  .00657, .01096,  gmcm2,  6,   0 
;Imager Top Kapton mylar, all regions,  3 or 5 mil mylar, oxygen
frac1, frac2, frac3, frac4, frac5, 1 1, 1, 1, 1,       1, 1,  .003504, .00584,  gmcm2,  8,   0 



;Imager Top Blankets, all regions,  5-12 layers of 0.25-0.5 mil mylar
;Carbon in Mylar
frac1, frac2, frac3, frac4, frac5, 1 1, 1, 1, 1,       5, 12,  .000548, .001096,  gmcm2,  6,   0 
;Oxygen in Mylar
frac1, frac2, frac3, frac4, frac5, 1 1, 1, 1, 1,       5, 12,  .000292, .000584,  gmcm2,  8,   0 

; Bottom of Imager
;Imager Bottom Kapton mylar, all regions,  3 or 5  mil mylar, carbon
frac1, frac2, frac3, frac4, frac5, 1 1, 1, 1, 1,       1, 1,  .00657, .01096,  gmcm2,  6,   0 
;Imager Top Kapton mylar, all regions,  3 or 5 mil mylar, oxygen
frac1, frac2, frac3, frac4, frac5, 1 1, 1, 1, 1,       1, 1,  .003504, .00584,  gmcm2,  8,   0 

;Imager Bottom Blankets, all regions,  5-12 layers of 0.25-0.5 mil mylar
;Carbon in Mylar
frac1, frac2, frac3, frac4, frac5, 1 1, 1, 1, 1,       5, 12,  .000548, .001096,  gmcm2,  6,   0 
;Oxygen in Mylar
frac1, frac2, frac3, frac4, frac5, 1 1, 1, 1, 1,       5, 12,  .000292, .000584,  gmcm2,  8,   0 



;Shutters

;Shutter 10, Thin shutter B, 
;1st region- 15 mils al  

frac1, frac2, frac3, frac4, frac5, 1, 0, 0, 0, 0     1, 1,  16.5,16.5.,  mils,  13,  1 
;2nd region is just like first region, 16 mils Al
frac1, frac2, frac3, frac4, frac5, 0, 1, 0, 0, 0     1, 1,  16.5.,16.5,  mils,  13,  1 

;3nd region is thick inner area. 40 mils Al.
frac1, frac2, frac3, frac4, frac5, 0, 0, 1, 0, 0,    1, 1,  38.5,38.5,  mils,  13,  1 
;4th region- 2.5 mils Al   
frac1, frac2, frac3, frac4, frac5, 0, 0, 0, 1, 0,    1, 1,  2.5, 2.5, mils,  13,  1 
;5th region- 2.5 mils Al
frac1, frac2, frac3, frac4, frac5, 0, 0, 0, 0, 1,    1, 1,  2.5, 2.5, mils,  13,  1 

;Shutter 01, Thick shutter A, 
;1st region- 59 mils Al
frac1, frac2, frac3, frac4,frac5,  1, 0, 0, 0, 0,       1, 1,   58,  58,  mils,  13,  2 

;2nd region- 18 mils Al, inner region is all 22 mils except slits.

frac1, frac2, frac3, frac4, frac5, 0, 1, 0, 0,0,        1, 1,   22,  22,  mils,  13,  2 
;3rd region- 22 mils Al   
frac1, frac2, frac3, frac4, frac5, 0, 0, 1, 0, 0,       1, 1,   22,  22,  mils,  13,  2 
;4rd region- 22 mils Al   
frac1, frac2, frac3, frac4, frac5, 0, 0, 0, 1, 0,       1, 1,   22,  22,  mils,  13,  2 

;5th region- 4 mils Al over small slit.
frac1, frac2, frac3, frac4, frac5, 0, 0, 0, 0, 1,      1, 1,   4,  4,  mils,  13,  2 


;Cryostat windows, all regions, 20 mil entrance window + 10 mil can window + two 5 mil internal thermal barriers of Be.

frac1, frac2, frac3, frac4, frac5, 1, 1, 1, 1, 1,      1, 1,   40.,  40.,  mils,  4,  0 


;Cryostat mylar, all regions,  7.25 mil mylar, carbon
frac1, frac2, frac3, frac4, frac5, 1 1, 1, 1, 1,       1, 1,  .015892, .015892,  gmcm2,  6,   0 

;Cryostat mylar, all regions,  7.25 mil mylar, oxygen
frac1, frac2, frac3, frac4, frac5, 1 1, 1, 1, 1,       1, 1,  .008468, .008468,  gmcm2,  8,   0 

;Summary of text read into structure hesi_win5 structure.
;** Structure HESSI_WIN5, 7 tags, length=72:
;   FRACTION        FLOAT     Array[5]  - fractional area in each of 5 regions
;   REGIONS         INT       Array[5]  - 1 indicates region populated with this material. 0 empty.
;   LAYERS          INT       Array[2]  - minimum and maximum number of layers
;   THICKNESS       FLOAT     Array[2]  - minimum and maximum thickness in UNITS
;   UNITS           STRING    ''	- UNITS mils or gmcm2 (gms/square cm)
;   Z               INT              0  - Z of material
;   ID              INT              0  - Association ID.
;     0.850000     0.0500000     0.0874000     0.0120000   0.000600000 1 1 1 1 1 1 1 .00657 .01096 gmcm2 6 0   
;     0.850000     0.0500000     0.0874000     0.0120000   0.000600000 1 1 1 1 1 1 1 .003504 .00584 gmcm2 8 0   
;     0.850000     0.0500000     0.0874000     0.0120000   0.000600000 1 1 1 1 1 5 12 .000548 .001096 gmcm2 6 0   
;     0.850000     0.0500000     0.0874000     0.0120000   0.000600000 1 1 1 1 1 5 12 .000292 .000584 gmcm2 8 0   
;     0.850000     0.0500000     0.0874000     0.0120000   0.000600000 1 1 1 1 1 1 1 .00657 .01096 gmcm2 6 0   
;     0.850000     0.0500000     0.0874000     0.0120000   0.000600000 1 1 1 1 1 1 1 .003504 .00584 gmcm2 8 0   
;     0.850000     0.0500000     0.0874000     0.0120000   0.000600000 1 1 1 1 1 5 12 .000548 .001096 gmcm2 6 0   
;     0.850000     0.0500000     0.0874000     0.0120000   0.000600000 1 1 1 1 1 5 12 .000292 .000584 gmcm2 8 0   
;     0.850000     0.0500000     0.0874000     0.0120000   0.000600000 1 0 0 0 0 1 1 16. 16. mils 13 1   
;     0.850000     0.0500000     0.0874000     0.0120000   0.000600000 0 1 0 0 0 1 1 16. 16. mils 13 1   
;     0.850000     0.0500000     0.0874000     0.0120000   0.000600000 0 0 1 0 0 1 1 40. 40. mils 13 1  
;     0.850000     0.0500000     0.0874000     0.0120000   0.000600000 0 0 0 1 0 1 1 2.0 2.0 mils 13 1  
;     0.850000     0.0500000     0.0874000     0.0120000   0.000600000 0 0 0 0 1 1 1 2.0 2.0 mils 13 1  
;     0.850000     0.0500000     0.0874000     0.0120000   0.000600000 1 0 0 0 0 1 1 60 60 mils 13 2  
;     0.850000     0.0500000     0.0874000     0.0120000   0.000600000 0 1 0 0 0 1 1 19 19 mils 13 2  
;     0.850000     0.0500000     0.0874000     0.0120000   0.000600000 0 0 1 0 0 1 1 19 19 mils 13 2  
;     0.850000     0.0500000     0.0874000     0.0120000   0.000600000 0 0 0 1 0 1 1 19 19 mils 13 2  
;     0.850000     0.0500000     0.0874000     0.0120000   0.000600000 0 0 0 0 1 1 1 2.0 2.0 mils 13 2  
;     0.850000     0.0500000     0.0874000     0.0120000   0.000600000 1 1 1 1 1 1 1 40. 40. mils 4 0  
;     0.850000     0.0500000     0.0874000     0.0120000   0.000600000 1 1 1 1 1 1 1 .015892 .015892 gmcm2 6 0   
;     0.850000     0.0500000     0.0874000     0.0120000   0.000600000 1 1 1 1 1 1 1 .008468 .008468 gmcm2 8 0   
;
; The fractional areas yield these areas in mm^2
;IDL> print,fractions * (5.9/2)^2*!pi*100
;      2323.88      136.699      238.949      32.8077      1.64038

