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Are magnetic fields and outflows aligned in protostellar cores?

Are magnetic fields and outflows aligned in protostellar cores?. Chat Hull University of California, Berkeley (USA) Radio Astronomy Laboratory 5 February 2013 Session: Magnetic Fields in the ISM and Star-forming Regions I Magnetic Fields in the Universe IV

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Are magnetic fields and outflows aligned in protostellar cores?

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  1. Are magnetic fields and outflows aligned in protostellar cores? Chat Hull University of California, Berkeley (USA) Radio Astronomy Laboratory 5 February 2013 Session: Magnetic Fields in the ISM and Star-forming Regions I Magnetic Fields in the Universe IV Playa del Carmen, Quintana Roo, México

  2. Simple model of SF with B-fields Credit: Bill Saxton, Harvard-Smithsonian Center for Astrophysics

  3. Misalignment of B-fields and outflows IRAS 4A VLA 1623 IRAS 16293 Rao+ 2009 Holland+ 1996 Outflow Girart+ 2006 B-field

  4. CARMACombined Array for Research in Millimeter-wave AstronomyConsortium: Berkeley, Caltech, Illinois, Maryland, Chicago • 6 ⨯10-m, 9 ⨯ 6-m, 8 ⨯ 3.5-m telescopes • Observations at 1 cm, 3 mm, and 1 mm (polarization!) • Located in Cedar Flat, CA (near Bishop)

  5. 1 mm dual-polarization receivers SIS mixers Orthomode transducer Waveguide circular polarizer WBA13 I.F. amplifiers (1-9 GHz) 1 inch Credit: Dick Plambeck

  6. TADPOL survey 35 sources Triples number of interferometric polarization maps ~300 observing hours CARMA C, D, & E arrays 1 – 4" resolution 10⨉higher resolution than CSO& JCMT Probes intermediate region between ~0.1 pc (single-dish) and ~100 AU (ALMA) 1 mm wavelength Ideal for dust polarization, as well as CO(2-1) for outflow mapping ≠ 75 seconds

  7. TADPOL collaboration • UC Berkeley Chat Hull (PI), Dick Plambeck, Mel Wright, Carl Heiles, Geoff Bower • University of Maryland Marc Pound, Alberto Bolatto, Katherine Jameson, Lee Mundy • Caltech ThusharaPillai, John Carpenter, James Lamb, NikolausVolgenau • University of Illinois, Urbana-Champagne Ian Stephens, Leslie Looney, Woojin Kwon, Dick Crutcher, Nick Hakobian • Other Dan Marrone (Arizona), Meredith Hughes (Wesleyan), John Vaillancourt & GöranSandell (USRA-SOFIA), John Tobin (NRAO), Jason Fiege (Manitoba), Erica Franzmann (Manitoba), Martin Houde (UWO, Caltech), Brenda Matthews (NRC-CNRC)

  8. TADPOL results L1157

  9. TADPOL results NGC 1333-IRAS 2A NGC 1333-IRAS 4A

  10. TADPOL results NGC 1333-IRAS 4B Ser-emb8

  11. Outflow vs. B-field: distribution Simulation: outflows & B-fields aligned within a 20º cone (tightly aligned) Simulation: outflows & B-fields aligned between 70–90º (preferentially misaligned) Simulation: outflows & B-fields are randomly oriented Cumulative Distribution Function (CDF) • KS-test results: • 20º cone ruled out ( p-value ~ 10-9 ) • Misaligned ( 0.79 ) and random ( 0.64 ) cannot be ruled out Hull+ 2012, submitted to ApJL Preprint: arXiv:1212.0540 (Projected) angle between outflow & B-field (deg)

  12. Conclusions • B-fields are either preferentially misaligned (perp.) or randomly aligned with respect to outflows at the ~1000 AU scale • Thus, circumstellar disks are misaligned with fields in the cores from which they formed • Future work: • Compare polarization in filaments with ALMA data • Compare B-fields in SCUBA (~0.1 pc) and CARMA (~1000 AU, or ~0.05 pc) data • TADPOL results: arXiv:1212.0540 • TADPOL survey (CARMA key project): tadpol.astro.illinois.edu • Questions? Contact Chat Hull: chat@astro.berkeley.edu

  13. Fin

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