IAU radial velocity standards

Measurements have also been conducted on spectra of IAU radial velocity standards. Most observations were conducted at dispersions of 40 and 80 A/mm. Arcturus was observed repeatedly but some hotter stars with sharp lines were also studied. The plates were scanned on the RGO PDS machine and the results show that the radial velocities measured are consistent with the IAU scale. In each case the standard deviation is quoted for the uncertainty.

1. At 40 A/mm for 18 observations of 5 IAU standards, the mean difference spectrograph - IAU = +0.2 +- 1.9,km/s
2. At 40 A/mm for 11 observations of Arcturus, the difference (standard deviation from IAU value) was 1.1,km/s
3. At 40 A/mm for 13 observations of 9 other stars, the mean difference spectrograph - IAU = -0.8 +- 3.9,km/s
4. At 40 A/mm for 5 observations of 5 stars (1 IAU standard), the mean difference spectrograph - IAU = -2.2 +- 7.6,km/s
5. At 40 A/mm for 6 observations of 4 stars (1 IAU standard), the mean difference spectrograph - IAU = -0.8 +- 4.8,km/s

The commissioning data were obtained by D.J. Stickland and R.P. Edwin.