SCUBA-2 with FTS and 80K blackbody source

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net := Tel ⋅Tel rows( Tel_optics) + 1, 4 rows( Tel_optics) + 1, 3 Tel 4 7 , FTSnettrans := net⋅FTStrans FTS photon NEP: pnFTSi := Total squared photon NEP for both sides of FTS and blackbody pnFTS 10 32 − ⋅ Photnoise2 εFTS i ν watt = Hz i := 0.. 12 ( , , Δν , Tel , T 4, 5 FTSi, nt i) 1032 Hz ⋅ watt 2 0 1 2 3 4 5 6 7 8 9 10 11 12 ( ) 2 1032Hz ⋅ := PhotonNoiseMather Tel ⋅pW, ν , FTSnettrans⋅0.2, FTSload 4, 6 T Tel 10 4, 7 32 − watt ⋅ ⋅ 6.466 10 Hz 17 − watt = × Hz 0 3.718 0.491 1.577 0.505 0.505 0.506 0.506 0.507 0.507 0.509 0.509 1.637 0.741 10 17 − watt Hz net transmission from pickoff mirror to detector Net transmission through full FTS to detector watt 2 Method 2: Squared Photon NEP for each FTS element, using Waynes NEP equation FTS photon NEP: ⎛ ⎜ ⎝ ∑ i pn FTSi FTSnettrans = 0.231 Compute the net transmission for each element (one side of FTS), working back from the feed optics Method 1: Total Photon NEP from FTS, approximated using total FTS loading and estimate of average emissivity ⎞⋅ ⎟ ⎠ TFTS := ⎛ ⎜ ⎜ ⎜ ⎜ ⎜ ⎜ ⎜ ⎜ ⎜ ⎜ ⎜ ⎜ ⎜ ⎜ ⎜ ⎜ ⎝ FTSload T 280K 280K 280K 280K 280K 280K 280K 280K 280K 280K 280K 280K ⎞ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎠ FTS temperatures net = 0.528 εFTS := 10 32 − watt ⋅ 4.673 10 Hz 17 − watt = × Hz ⎛ ⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎝ 1 εM εBS εM εM εM εM εM εM εM εM εBS εM ⎞ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎠ nt := FTS emissivities ⎛ ⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎜⎝ 2Tr BS 2 TrM 5 2Tr BS 2 TrM 5 2Tr BS Tr M 5 Tr BS Tr M 4 Tr BS Tr M 4 Tr BS Tr M 3 Tr BS Tr M 3 Tr BS Tr M 2 Tr BS Tr M 2 Tr BS Tr M Tr BS Tr M Tr M 1 ⎞ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟⋅ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎠ net FTS net transmissions
Total background power from sky, all optics, plus 'telescope side' and 'blackbody side' of FTS i := 1.. ( nr − 2) Background due to sky P := Background due to primary and membrane kkk := rows( Tel_optics) .. ( nr − rows( Det_optics) − 1) Background due to FTS Background due to stop ∑ Total loading without FTS was: Look at the individual background power levels i Tel ⋅pW i, 6 Psky := Tel ⋅pW 1, 6 PS := Tel ⋅pW 2, 6 Pfts := FTSpower⋅pW P = 11.637 pW P = 7.946 pW PStop := Tel ⋅pW nr−8, 6 Psky = 1.427pW PS = 1.208pW Pfts = 7.343pW PStop 1.183 10 4 − = × pW Psky = 0.123 P PS P = 0.104 Pfts = 0.631 P PStop = P 1.017 10 5 − ×
Page 1 and 2: SCUBA-2 photon noise model at 850 m
Page 3: Combine the two matrices into the t
Page 7 and 8: Loading (pW) 5. Now calculate the p
Page 9 and 10: Aperture Efficiency 0.8 0.69 0.57 0
Page 11 and 12: 8. Variation of NEFD and total back
Page 13 and 14: NEFD Total Power (pW) 1 .10 3 100 1
Page 15: Maximum power handling from non-FTS

SCUBA-2 with FTS and 80K blackbody source

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