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arXiv · 1703.03035

Velocity centroid gradients for absorbing media

Diego F. González-Casanova·A. Lazarian·Blakesley Burkhart
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Abstract

We explore how the velocity gradient technique (VGT) can be applied to absorbing media in the case of$^{13}$CO 2-1 emission. The VGT is a new way to trace magnetic fields in the plane of the sky using only spectroscopic observations. We apply the VGT to magnetohydrodynamic turbulence simulations that have been post-processed to include $^{13}$CO 2-1 emission and we calculate the velocity centroid gradients. We find that the velocity centroid gradients trace the projected magnetic field in media with different $^{13}$CO abundances, densities and optical depths. Our study opens up the possibility of using velocity centroid gradients to trace magnetic fields in molecular clouds using 13CO emission.

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Diego F. González-Casanova, A. Lazarian, Blakesley Burkhart. 2017-03-08. Velocity centroid gradients for absorbing media. https://doi.org/10.1093/mnras/sty2775

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