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Table 8.

Focal plane masks in the SPHERE visual coronagraph.

Name p ρ Remark max(ct6n)
NC_WF Clear 7983 7813
NC_NF Clear
CLC_S_WF + 46.5 72 52
CLC_M_WF 77.5 26 13
CLC_MT_WF + 77.5 astrom. mask
CLC_L_WF 155 31 11
CLC_XL_WF 538 7.5 2.7
CLC_S_NF + 46.5 Not tested
CLC_M_NF 77.5 Not tested
4QPM1 + λ0 = 666 nm
4QPM2 + λ0 = 823 nm
Bar w = 155 mas

Notes. The first column gives the mask name where NC stands for no coronagraph, CLC for classical Lyot coronagraph, 4QPM for four quadrant phase mask, WF for wide field (radius ρ = 4″), NF for narrow field (1″×1″). Masks on plates p are indicated in the second column and ρ is the mask radius in μm and converted to mas using the scale 0.86 mas μm−1. The last two columns give the maximum normalized counts for the α Hyi tests (Fig. 16) for the R_PRIM and I_PRIM filters, respectively.

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