Open Access
Table 1
Keck/NIRC2 vortex coronagraph observation log.
| Target filter | Vega Ms band | |
|---|---|---|
| UT date | 2018 Aug. 30 | 2019 Aug. 20 |
| UT start | 05:15:26.35 | 06:35:47.62 |
| UT end | 07:15:00.52 | 10:12:23.95 |
| Airmass (a) | 1.066 ± 0.009 | 1.159 ± 0.101 |
| DIMM seeing (a,b) | 0″.42 ± 0″.11 | 1″.18 ± 0″.55 |
| MASS seeing (a,b) | 0″.16 ± 0″.06 | 0″.18 ± 0″.08 |
| Precipitable water vapor level | ~7 mm | ~2 mm |
| Parallactic angle change | 74°9 | 81°.6 |
| Single integration time | 0.181 s | 0.25s |
| Coadd for single frame | 100 | 150 |
| Total frame count | 110 | 120 |
| On-target integration time | 1991 s | 4500 s |
| Total on-target time | 1.803 h | |
| Pixel scale | 9.942 mas | |
Notes – (a)The uncertainties in this paper are 1σ unless otherwise specified. (b)Calculated during this observation using http://mkwc.ifa.hawaii.edu/current/seeing/index.cgi.
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