Statistics of Velocity from Spectral Data: Modified Velocity Centroids

  title={Statistics of Velocity from Spectral Data: Modified Velocity Centroids},
  author={A.Lazarian and Alejandro Esquivel},
  journal={The Astrophysical Journal},
We address the problem of studying interstellar turbulence using spectral line data. We find a criterion when the velocity centroids may provide trustworthy velocity statistics. To enhance the scope of centroid applications, we construct a measure that we term "modified velocity centroids" (MVCs) and derive an analytical solution that relates the two-dimensional spectra of the modified centroids with the underlying three-dimensional velocity spectrum. We test our results using synthetic maps… Expand

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