High-resolution spectroscopy for Cepheids distance determination V. Impact of the cross-correlation method on the p-factor and the γ-velocities

  title={High-resolution spectroscopy for Cepheids distance determination V. Impact of the cross-correlation method on the p-factor and the $\gamma$-velocities},
  author={Nicolas Nardetto and Wolfgang Gieren and Pierre Kervella and P Fouqu{\'e} and Jesper Storm and G. Pietrzynski and Denis Mourard and Didier Queloz},
  journal={Astronomy and Astrophysics},
Context: The cross correlation method (hereafter CC) is widely used to derive the radial velocity curve of Cepheids when the signal to noise ratio of the spectra is low. However, if it is used with an inaccurate projection factor, it might introduce some biases in the Baade-Wesselink (BW) methods of determining the distance of Cepheids. In addition, it might affect the average value of the radial velocity curve (or γ-velocity) important for Galactic structure studies. Aims: We aim to derive a… Expand

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