We use an improved wavelet analysis technique to reconstruct the (U,V,W) velocity distribution for ≈ 250000 stars from Gaia DR2, located in the solar neighborhood of 200 pc. The 2D wavelet transforms for three bivariate distributions (U,V) , (U,W) , and (V,W) were investigated. Though most of currently known (low-velocity) stellar moving groups are densely overlapped in these diagrams, our analysis allowed us to detect and disentangle about twenty statistically significant 3D groups of stars with high velocities. Most of them appear to be new discoverirs. We also discuss the issue of correct noise thresholding in the wavelet transform and highlight the importance of using a global rather than local statistic for that. Using of a local significance measure may lead to an overstated statistical confidence for individual patterns due to the effect of multiple testing.

Original languageEnglish
Pages (from-to)141-168
Number of pages28
JournalActa Astronomica
Volume70
Issue number2
DOIs
StatePublished - Jun 2020

    Research areas

  • Galaxy: Kinematics and dynamics, Methods: Statistical, Solar neighborhood, STREAMS, Galaxy: kinematics and dynamics, Methods: statistical, FIELD, STELLAR, STARS, solar neighborhood, PLANET SEARCH, JITTER

    Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

ID: 62915381