Infrared-excess white dwarfs in the Gaia 100 pc sample
  We analyse the 100pc Gaia white dwarf volume-limited sample by means of VOSA
(Virtual Observatory SED Analyser) with the aim of identifying candidates for
displaying infrared excesses. Our search focuses on the study of the spectral
energy distribution (SED) of 3,733 white dwarfs with reliable infrared
photometry and GBP-GRP colours below 0.8 mag, a sample which seems to be nearly
representative of the overall white dwarf population. Our search results in 77
selected candidates, 52 of which are new identifications. For each target we
apply a two-component SED fitting implemented in VOSA to derive the effective
temperatures of both the white dwarf and the object causing the excess. We
calculate a fraction of infrared-excess white dwarfs due to the presence of a
circumstellar disk of 1.6+-0.2%, a value which increases to 2.6+-0.3% if we
take into account incompleteness issues. Our results are in agreement with the
drop in the percentage of infrared excess detections for cool (<8,000K) and hot
(>20,000K) white dwarfs obtained in previous analyses. The fraction of white
dwarfs with brown dwarf companions we derive is ~0.1-0.2%.
