OBSERVATIONS OF ENHANCED RADIATIVE GRAIN ALIGNMENT NEAR HD 97300

Journal Article · Fri Sep 10 04:00:00 EDT 2010 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/720/2/1045· OSTI ID:21460064

Andersson, B-G ^[1]

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1. SOFIA Science Center, USRA, NASA Ames Research Center, M.S. N211-3 Moffett Field, CA 94035 (United States)

We have obtained optical multi-band polarimetry toward sightlines through the Chamaeleon I cloud, particularly in the vicinity of the young B9/A0 star HD 97300. We show, in agreement with earlier studies, that the radiation field impinging on the cloud in the projected vicinity of the star is dominated by the flux from the star, as evidenced by a local enhancement in the grain heating. By comparing the differential grain heating with the differential change in the location of the peak of the polarization curve, we show that the grain alignment is enhanced by the increase in the radiation field. We also find a weak, but measurable, variation in the grain alignment with the relative angle between the radiation field anisotropy and the magnetic field direction. Such an anisotropy in the grain alignment is consistent with a unique prediction of modern radiative alignment torque theory and provides direct support for radiatively driven grain alignment.

• OSTI ID: 21460064
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 720; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
79 ASTRONOMY AND ASTROPHYSICS
ANISOTROPY
DUSTS
MAGNETIC FIELDS
POLARIMETRY
STARS