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New observations of the quasar HE0515$-$4414 have been made using the HARPSspectrograph on the ESO 3.6m telescope, aided by the Laser Frequency Comb(LFC). We present three important advances for $\alpha$ measurements in quasarabsorption spectra from these observations. Firstly, the data have beenwavelength calibrated using LFC and ThAr methods. The LFC wavelengthcalibration residuals are six times smaller than when using the standard ThArcalibration. We give a direct comparison between $\alpha$ measurements madeusing the two methods. Secondly, spectral modelling was performed usingArtificial Intelligence (fully automated, all human bias eliminated), includinga temperature parameter for each absorption component. Thirdly, in contrast toprevious work, additional model parameters were assigned to measure $\alpha$for each individual absorption component. The increase in statisticaluncertainty from the larger number of model parameters is small and the methodallows a substantial advantage; outliers that would otherwise contribute asignificant systematic, possibly corrupting the entire measurement, areidentified and removed, permitting a more robust overall result. The $z_{abs} =1.15$ absorption system along the HE0515$-$4414 sightline yields 40 new$\alpha$ measurements. We constrain spatial fluctuations in $\alpha$ to be$\Delta\alpha/\alpha \leq 9 \times 10^{-5}$ on scales $\approx 20\;{\rmkm\,s}^{-1}$, corresponding to $\approx25\;$kpc if the $z_{abs} = 1.15$ systemarises in a $1\;$Mpc cluster. Collectively, the 40 measurements yield$\Delta\alpha/\alpha=-0.27\pm2.41\times10^{-6}$, consistent with no variation.

A new era of fine structure constant measurements at high redshift