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Table 1

Pupil configuration of the Keck telescope and Lyot stop mask used for the vortex coronagraph in NIRC2.

Parameter Normalized value

Entrance pupil diam. 1.00
(circumscribed circle)
Central obstruction diam. 0.24
Entrance pupil spider width 0.0023
Inter-segment gap 2.7 × 10-4
Lyot stop external diameter 0.80
Lyot stop internal diameter 0.27
Lyot stop spider width 0.0061

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