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We present an accurate analysis of the H2 absorption lines from the zabs ~2.4018 damped Ly{\alpha} system towards HE 0027-1836 observed with the VeryLarge Telescope Ultraviolet and Visual Echelle Spectrograph (VLT/UVES) as apart of the European Southern Observatory Large Programme "The UVES largeprogramme for testing fundamental physics" to constrain the variation ofproton-to-electron mass ratio, {\mu} = mp/me. We perform cross-correlationanalysis between 19 individual exposures taken over three years and thecombined spectrum to check the wavelength calibration stability. We notice thepresence of a possible wavelength dependent velocity drift especially in thedata taken in 2012. We use available asteroids spectra taken with UVES close toour observations to confirm and quantify this effect. We consider single andtwo component Voigt profiles to model the observed H2 absorption profiles. Weuse both linear regression analysis and Voigt profile fitting where{\Delta}{\mu}/{\mu} is explicitly considered as an additional fittingparameter. The two component model is marginally favored by the statisticalindicators and we get {\Delta}{\mu}/{\mu} = (-2.5 +/- 8.1(stat) +/- 6.2(sys))ppm. When we apply the correction to the wavelength dependent velocity drift wefind {\Delta}{\mu}/{\mu} = (-7.6 +/- 8.1(stat) +/- 6.3(sys)) ppm. It will beimportant to check the extent to which the velocity drift we notice in thisstudy is present in UVES data used for previous {\Delta}{\mu}/{\mu}measurements.

The UVES Large Program for Testing Fundamental Physics II: Constraints on a Change in {\mu} Towards Quasar HE 0027-1836