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tokens: of individual absorption lines such as their width and asymmetries, but with a heightened signal to noise. The CCF is binned in 0.5 km s −1 increments, owing to the R = 55 000 resolving power of the spectrograph. Two different spectral type masks were used: G2 and K5. These were chosen based on the spectral type of the primary star, which in our sample ranges between K2 and F0. Dumusque et al. (2012) demonstrated that the closeness of the spectral type mask largely affects only the absolute radial velocity and not the radial velocity variations. Only having two spectral type masks therefore does not hinder our analysis. The CCF of each measurement was compared with a Thorium-Argon spectrum, which was used as a wavelength-calibration reference ( Lovis Pepe 2007 ). This accounted for variations in the instrument which would otherwise impose a drift on the measured radial velocity of the star. The main source of variation was the pressure of the spectrograph, which followed the ambient atmospheric pressure because CORALIE, unlike HARPS and HARPS-North, is not pressurised. In 2014 a Fabry-Pérot unit was added to provide even more precise calibrations. 5.2 Outlier removal For each CCF, which is approximately Gaussian, we measure the span of the bisector slope. The bisector is calculated by tracing vertically the midpoint of the CCF at each value of flux intensity. The span of the bisector slope is the difference between the bisector at the top and bottom of the CCF ( Queloz et al. 2001b ). The bisector therefore reflects any asymmetries in the absorption lines. We remove any observations with bisector positions more than three interquartile ranges below the first quartile or above the third quartile. Such outliers may be from the wrong star being observed accidentally, or an abnormally low signal to noise observation. A visual inspection was also done of the data to outliers in the CCF’s Full Width Half Maximum (FWHM). 5.3 Calculation of radial velocity uncertainties In Table A.1 three different σ radial velocity uncertainties are listed. The first value, σ 1800s , is mean the photon noise uncertainty for all observations of 1800 s, which was the typical observation length during the BEBOP programme. The value σ median is the median photon noise precision for all observations, that is both the 1800 s observations taken for BEBOP and earlier, shorter observations taken in the EBLM programme. Fig. 4 Time-series of 1519 radial velocity observations of the 47 eclipsing binaries in the BEBOP programme. Red diamonds are observations for 1700 s or longer. Blue squares are for shorter observations. It is seen that all binaries typically receive two long observations initially before a series of short observations as part of the EBLM programme. A series of long observations typically commenced near the end of 2013 as part of the BEBOP survey. After removing observations with significant outlier bisector values there may still remain some