The Local Stellar Velocity Field via Vector Spherical Harmonics

  title={The Local Stellar Velocity Field via Vector Spherical Harmonics},
  author={Vp Murphy},
  journal={The Astronomical Journal},
  • V. Murphy
  • Published 22 May 2007
  • Physics
  • The Astronomical Journal
We analyze the local field of stellar tangential velocities for a sample of 42,339 nonbinary Hipparcos stars with accurate parallaxes, using a vector spherical harmonic formalism. We derive simple relations between the parameters of the classical linear model (Ogorodnikov-Milne) of the local systemic field and low-degree terms of the general vector harmonic decomposition. Taking advantage of these relationships, we determine the solar velocity with respect to the local stars of (V_X, V_Y, V_Z… 

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