Previous abstract Next abstract
Session 24 - Star Formation in the Galaxy & the LMC.
Display session, Tuesday, June 10
South Main Hall,
The roles played by magnetic fields in the star-forming regions of the Milky Way Galaxy are largely unknown. To address this knowledge gap, we have developed a concept for a new, focused, small explorer mission. The Milky Way Magnetic Field Mapping Mission, or M4 will consist of a cryogenically cooled 40 cm aperture telescope illuminating twin 32 \times 32 pixel germanium arrays, already developed for SIRTF. Operating in a unique, no-moving-parts linear polarimetry mode, M4 will be used to measure the magnetic field structure in the dense interstellar medium. For broadband operation at 100\mum, M4 will be diffraction limited for a 60 arcsec beam, and pixel sampling of 24 arcseconds will support detailed model testing and superresolution image reconstruction. Since the expected linear polarization is around 2%, ensuring that M4 can map field geometry with better than 10^\circ uncertainty requires operations with S/N beyond 150. This challenge will be met by a combination of hardware, software, and operations/observing solutions.
The minimum cryogen lifetime of four months will permit mapping a large piece of the Milky Way (\pm 50^\circ of galactic longitude and \pm 5^\circ of latitude) in four weeks, much of the nearby Sco/Oph dark cloud region (three weeks), a significant piece of infrared cirrus (two weeks), and enable a very robust guest investigator program (at least 3 weeks duration) which is expected to highlight extragalactic observations.
The author(s) of this abstract have provided an email address for comments about the abstract: clemens@bu.edu