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We use deep multi-epoch PSF photometry taken with the Visible and InfraredSurvey Telescope for Astronomy (VISTA) to measure and analyze the propermotions of stars within the Galactic globular cluster 47 Tucanae (47 Tuc, NGC104). The observations are part of the ongoing near-infrared VISTA survey ofthe Magellanic Cloud system (VMC). The data analyzed here corresponds to oneVMC tile and covers a total sky area of 1.77 deg^2. Absolute proper motionswith respect to ~9070 background galaxies are calculated from a linearregression model applied to the stellar positions in 11 epochs in the Ksfilter. The data extend over a total time baseline of ~17 months. We found amedian proper motion of the stars within 47 Tuc of (mu_a cos(d), mu_d) = (+5.89+/- 0.02(stat) +/- 0.13(sys), -2.14 +/- 0.02(stat) +/- 0.08(sys)) mas/yr, basedon the measurements of ~35000 individual sources between 5' and 42' from thecluster center. We compared our result to the proper motions from the newest USNaval Observatory CCD Astrograph Catalog (UCAC5) which includes data from theGaia data release 1. Selecting cluster members (~2700 stars) we found a medianproper motion of (mu_a cos(d), mu_d) = (+5.30 +/- 0.03(stat) +/- 0.70(sys),-2.70 +/- 0.03(stat) +/- 0.70(sys)) mas/yr. The values derived from the VMCdata are consistent with the UCAC5 result, and are close to literaturemeasurements obtained using HST. We combined our results with literature radialvelocity measurements and reconstructed the orbit of 47 Tuc, finding that thecluster is on a low-ellipticity orbit and is confined within the inner ~7.5 kpcof the Galaxy. We show that the use of an increased time baseline combined withPSF-determined stellar centroids in crowded regions significantly improves theaccuracy of the method. In future works, we will apply this method to more VMCtiles to study in detail the kinematics of the Magellanic Clouds.

The VMC survey XXVIII. Improved measurements of the proper motion of the Galactic globular cluster 47 Tucanae