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Table 1.
Astrometric measurements and calibrations of all observation epochs.
| Epoch | Instrument | Pixel scale (mas/pixel) | True north (deg) | Separation (arcsec) | Position angle (deg) |
|---|---|---|---|---|---|
| 1998.1339 | WFPC2 | 45.52 ± 0.01 | 31.69 ± 0.005 | 1.314 ± 0.039 | 258.26 ± 1.21 |
| 2006.1311 | NACO | 13.24 ± 0.18 | 0.18 ± 1.24 | 1.299 ± 0.018 | 260.30 ± 1.24 |
| 2017.1311 | SPHERE/IRDIS | 12.263 ± 0.009 | −1.71 ± 0.06 | 1.314 ± 0.002 | 261.41 ± 0.12 |
| 2017.4617 | SPHERE/IRDIS | 12.251 ± 0.009 | −1.75 ± 0.11 | 1.319 ± 0.001 | 261.40 ± 0.23 |
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