From:	LYA::PRYOR        11-MAY-1992 21:47:31.42
To:	SIMMONS, LRSP::KTOBISKA
CC:	
Subj:	euv wavelength scale

From:	LOONEY::SANDEL       27-NOV-1990 17:22:38.38
To:	ZODIAC::PRYOR, SANDEL
CC:	
Subj:	EUV sensitivity et al.

Wayne,
     I think that a linear wavelength scale is fine.  I have been
using a scale that puts He 584 in channel 5.81 and H Ly alpha in
112.70.  This gives

     wavelength (A) = 549.63 + 5.913*channel
or
     channel = -92.96 + 0.169125*wavelength (A).

The numbers that went into the sensitivity curve in the
instrument paper follow:

wvlgnth    sens        sigma

58.4       39.3        6.9              wavelength in nm
62.6       40.6        15.              sens in count/sec/kR
67.8       34.1        5.5              sigma in count/sec/kR
74.0       32.8        8.0
82.7       30.6        9.0
90.6       26.6        4.6
102.5      18.2        3.2
104.8      13.8        2.4
110.7      8.04        1.3
116.0      4.49        0.72
121.6      3.78        0.64

58.4       38.8        6.8
88.7       27.5        5.0
92.4       26.0        4.9
96.4       18.2        3.6
103.0      17.3        3.0
106.0      10.5        1.8
121.6      3.35        0.56

Could you send me the numbers in the WIB spectrum?
The spectrum of Venus that we made from the IDL data file seems
to show something just longward of He 584, but it doesn't show up
in the WIB plot you sent (?).
Cheers, Bill