Gravitational Lensing Analysis of the Kilo Degree Survey
  The Kilo-Degree Survey (KiDS) is a multi-band imaging survey designed for
cosmological studies from weak lensing and photometric redshifts. It uses the
ESO VLT Survey Telescope with its wide-field camera OmegaCAM. KiDS images are
taken in four filters similar to the SDSS ugri bands. The best-seeing time is
reserved for deep r-band observations that reach a median 5-sigma limiting AB
magnitude of 24.9 with a median seeing that is better than 0.7arcsec.
  Initial KiDS observations have concentrated on the GAMA regions near the
celestial equator, where extensive, highly complete redshift catalogues are
available. A total of 109 survey tiles, one square degree each, form the basis
of the first set of lensing analyses, which focus on measurements of halo
properties of GAMA galaxies. 9 galaxies per square arcminute enter the lensing
analysis, for an effective inverse shear variance of 69 per square arcminute.
Accounting for the shape measurement weight, the median redshift of the sources
is 0.53.
  KiDS data processing follows two parallel tracks, one optimized for galaxy
shape measurement (for weak lensing), and one for accurate matched-aperture
photometry in four bands (for photometric redshifts). This technical paper
describes how the lensing and photometric redshift catalogues have been
produced (including an extensive description of the Gaussian Aperture and
Photometry pipeline), summarizes the data quality, and presents extensive tests
for systematic errors that might affect the lensing analyses. We also provide
first demonstrations of the suitability of the data for cosmological
measurements, and explain how the shear catalogues were blinded to prevent
confirmation bias in the scientific analyses.
  The KiDS shear and photometric redshift catalogues, presented in this paper,
are released to the community through http://kids.strw.leidenuniv.nl .
