Sensitivity of coded mask telescopes

Applied Optics

Volumn 47, Issue 15, 2008, Pages 2739-2749

  Skinner, Gerald K ^a,b  

^a UNIVERSITY OF MARYLAND   (United States)

^b NASA GODDARD SPACE FLIGHT CENTER   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

GAMMA RAYS; IMAGE RESOLUTION; SOURCE SEPARATION;

ASTRONOMICAL TELESCOPES; GAMMA RAY TELESCOPE; GENERAL EXPRESSION; GRID STRUCTURES; LIMITED SENSITIVITY; POISSON NOISE; SOURCE LOCATION; SPATIAL RESOLUTION;

TELESCOPES;

EID: 49749084749     PISSN: 1559128X     EISSN: 15394522     Source Type: Journal    
DOI: 10.1364/AO.47.002739     Document Type: Article

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52. This illustrates an approximation in the approach used here. The shadow of a source at trial positions away from the peak cannot be totally independent of that expected for a source at the peak position [53]. The process described here is equivalent to correlation with a mean-subtracted form of the expected count distribution, which must produce a function with a mean of zero. Thus, a positive peak implies a negative mean level elsewhere. The effect goes inversely with the number of resolution elements in the field of view and becomes negligible for sufficiently large N.
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57. B were totals for all the pixels of a particular category.
58. s - 1) is used for a better approximation but the differences are small in practical cases.