천문학회지 (Journal of The Korean Astronomical Society)

  • 제40권4호
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  • Pages.113-118
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  • 2007
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  • 1225-4614(pISSN)
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  • 2288-890X(eISSN)
한국천문학회 (The Korean Astronomical Society)
권호 표지
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POLARIZATION OF FIR EMISSION FROM T TAURI DISKS

  • Cho, Jung-Yeon (Dept. of Astronomy & Space Science, Chungnam National Univ.) ;
  • Lazarian, A. (Astronomy Dept., Univ. of Wisconsin)
  • 발행 : 2007.12.31
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초록

Recently far infra-red (FIR) polarization of the $850{\mu}m$ continuum emission from T Tauri disks has been detected. The observed degree of polarization is around 3 %. Since thermal emission from dust grains dominates the spectral energy distribution at the FIR regime, dust grains might be the cause of the polarization. We explore alignment of dust grains by radiative torque in T Tauri disks and provide predictions for polarized emission for disks viewed at different wavelengths and viewing angles. In the presence of magnetic field, these aligned grains produce polarized emission in infrared wavelengths. When we take a Mathis-Rumpl-Nordsieck-type distribution with maximum grain size of $500-1000{\mu}m$, the degree of polarization is around 2-3 % level at wavelengths larger than ${\sim}100{\mu}m$. Our study indicates that multifrequency infrared polarimetric studies of protostellar disks can provide good insights into the details of their magnetic structure.

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참고문헌

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