Table 2
System parameters and resulting noise.
| EHI system | EHI+ system | ||||||
|---|---|---|---|---|---|---|---|
| M87* | NGC 1052 | M87* | |||||
| ν (GHz) | 230 | 560 | 43 | 43 | 560 | 5000 | |
| D (m) | 4.0 | 15.0 | |||||
| Tsys (K) | 150 | 50 | 300 | ||||
| ηap | 0.58 | 0.58 | |||||
| ηcor | 0.97 | 0.97 | |||||
| ηclock | 0.87 | 0.87 | |||||
| Δν (GHz) | 5 | 25 | 450 | ||||
| tint,centre (s) | 452.2 | 452.2 | |||||
| tint,edge (s) | 65.67 | 27.12 | 87.82 | 6.99 | 27.12 | 3.02 | |
| SEFD (Jy) | 6.7 × 104 | 1.6 × 103 | |||||
| σcentre (Jy) | 0.036 | 0.00038 | |||||
| σedge (Jy) | 0.094 | 0.15 | 0.082 | 0.29 | 0.0016 | 0.0047 | |
Notes. σ-values are calculated with Eqs. (2) and (3) for 30 km orbital separation at the centre (long integration time) and edge (short integration time) of the uυ-spiral. Integration time at the edge of the uυ-spiral tint,edge at 43 GHz is different for NGC 1052 and M87* due to different fields of view (FoVs).
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