Far-infrared polarimetry from the Stratospheric Observatory for Infrared Astronomy
Multi-wavelength imaging polarimetry at far-infrared wavelengths has proven to be an excellent tool for studying the physical properties of dust, molecular clouds, and magnetic fields in the interstellar medium. Although these wavelengths are only observable from airborne or space-based platforms, no first-generation instrument for the Stratospheric Observatory for Infrared Astronomy (SOFIA) is presently designed with polarimetric capabilities. We study several options for upgrading the High-resolution Airborne Wideband Camera (HAWC) to a sensitive FIR polarimeter. HAWC is a 12 × 32 pixel bolometer camera designed to cover the 53−215 μm spectral range in 4 colors, all at diffraction-limited resolution (5−21 arcsec). Upgrade options include: (1) an external set of optics which modulates the polarization state of the incoming radiation before entering the cryostat window; (2) internal polarizing optics; and (3) a replacement of the current detector array with two state-of-the-art superconducting bolometer arrays, an upgrade of the HAWC camera as well as polarimeter. We discuss a range of science studies which will be possible with these upgrades including magnetic fields in star-forming regions and galaxies and the wavelength-dependence of polarization.
Additional Information© 2007 Society of Photo-Optical Instrumentation Engineers (SPIE). We would like to thank Fabian Heitsch, Jungyeon Cho, Diego Falceta-Gon¸calves, Megan Krejny, Jesse Wirth, Harvey Moseley, and Leslie Looney for useful discussions regarding the material in this manuscript. This work has been partially supported by NSF grants 0505124 to the University of Chicago, AST-0540882 to the California Institute of Technology, and AST-0505230 to Northwestern University. A.L. acknowledges support from the NSF Center for Magnetic Self-Organization in Laboratory and Astrophysical Plasmas and grant AST-0507164. R.M.C. acknowledges partial support from NSF grant AST-0606822.
Published - 66780D.pdf