The VMC Survey. XVIII. Radial dependence of the low-mass, 0.55--0.82
  $M_\odot$ stellar mass function in the Galactic globular cluster 47 Tucanae
  We use near-infrared observations obtained as part of the {\sl Visible and
Infrared Survey Telescope for Astronomy} (VISTA) Survey of the Magellanic
Clouds (VMC), as well as two complementary {\sl Hubble Space Telescope} ({\sl
HST}) data sets, to study the luminosity and mass functions as a function of
clustercentric radius of the main-sequence stars in the Galactic globular
cluster 47 Tucanae. The {\sl HST} observations indicate a relative deficit in
the numbers of faint stars in the central region of the cluster compared with
its periphery, for $18.75\leq m_{\rm F606W}\leq 20.9$ mag (corresponding to a
stellar mass range of $0.55<m_\ast/{M_\odot}<0.73$). The stellar number counts
at $6.7'$ from the cluster core show a deficit for $17.62\leq m_{\rm F606W}\leq
19.7$ mag (i.e., $0.65<m_\ast/{M_\odot}<0.82$), which is consistent with
expectations from mass segregation. The VMC-based stellar mass functions
exhibit power-law shapes for masses in the range $0.55<m_\ast/{M_\odot}< 0.82$.
These power laws are characterized by an almost constant slope, $\alpha$. The
radial distribution of the power-law slopes $\alpha$ thus shows evidence of the
importance of both mass segregation and tidal stripping, for both the first-
and second-generation stars in 47 Tuc.
