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Kinematics and morphology of the Narrow-Line Region in the Seyfert galaxy NGC1386

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 نشر من قبل Joern Rossa
 تاريخ النشر 2000
  مجال البحث فيزياء
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We present a high spatial and spectral resolution 2-D echelle spectrogram of the Narrow-Line Region in the Seyfert 2 galaxy NGC1386. This Seyfert galaxy was observed with CASPEC in the wavelength range 5270-7725 Angstrom which covers the H-alpha and the [N II] lines. With the use of spatially high resolved images taken with the WFPC2 aboard the Hubble Space Telescope we could identify individual components of the Narrow-Line Region in our spectra. A Gaussian decomposition of the spectra revealed 9 distinct emission-line complexes. The brightest component is blue-shifted by -120+-10 km/s with respect to the systemic velocity and shows an offset of -1.6 relative to the nucleus of the galaxy. The true nucleus of NGC1386 has a much lower apparent H-alpha luminosity than this component. The nucleus is probably highly absorbed. Although the majority of the Narrow-Line Region components follows a regular velocity field, we find evidence for a separate kinematic component. The Narrow-Line Region is aligned anti-parallel to the radio-jet which propagates from the center of NGC1386 to the south.

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