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Spectroscopy and 3D imaging of the Crab nebula

Andrej Cadez·Alberto Carraminana·Simon Vidrih
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Abstract

Spectroscopy of the Crab nebula along different slit directions reveals the 3 dimensional structure of the optical nebula. On the basis of the linear radial expansion result first discovered by Trimble (1968), we make a 3D model of the optical emission. Results from a limited number of slit directions suggest that optical lines originate from a complicated array of wisps that are located in a rather thin shell, pierced by a jet. The jet is certainly not prominent in optical emission lines, but the direction of the piercing is consistent with the direction of the X-ray and radio jet. The shell's effective radius is ~ 79 seconds of arc, its thickness about a third of the radius and it is moving out with an average velocity 1160 km/s.

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Andrej Cadez, Alberto Carraminana, Simon Vidrih. 2004-03-05. Spectroscopy and 3D imaging of the Crab nebula. https://doi.org/10.1086/421234

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