Bibcode
Andersson, B.-G.; Vaillancourt, John E.; Acosta-Pulido, J. A.; Fernandez, Manuel
Bibliographical reference
American Astronomical Society, AAS Meeting #227, id.#424.05
Advertised on:
1
2016
Citations
0
Refereed citations
0
Description
Interstellar dust grain alignment gives rise to polarization from UV to
mm wavelengths, allowing the study of the geometry and strength of the
magnetic field. Over the last couple of decades observations and theory
have led to the establishment of the Radiative Alignment Torque (RAT)
mechanism as the leading candidate to explain the effect. With a
quantitatively well constrained theory, polarization can be used not
only to study the interstellar magnetic field, but also the dust and
other environmental parameters. Photo-dissociation Regions (PDRs), with
their intense, anisotropic radiation fields, consequent rapid H2
formation, and high spatial density-contrast provide a rich environment
for such studies. Here we discuss an expanded optical, NIR and mm-wave
study (cf. Andersson et al. 2013) of the IC 63 reflection nebula,
showing strong H2 formation-enhanced alignment and the first direct,
empirical, evidence for disalignment due to gas-grain collisions.