The Class 0 Source Barnard 1c (most recent results ) Brenda Matthews Herzberg Institute of Astrophysics National Research Council of Canada

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1 The Class 0 Source Barnard 1c (most recent results ) Brenda Matthews Herzberg Institute of Astrophysics National Research Council of Canada Edwin Bergin (University of Michigan) Antonio Crapsi & Michiel Hogerheijde (Leiden Observatory) Jes Jørgensen & Dan Marrone (CfA) Ramprasand Rao (ASIAA) Al Wootten (NRAO)

2 Barnard 1c: A Dense Core in Perseus Bachiller et al. (1990) IRAC; Jørgensen et al. (2006) 2

3 Spectroscopy of B1c: Outflow Spitzer 4.5 µm: Jørgensen et al CO 1-0 (BIMA array): Matthews et al. 2006, ApJ, 653, in press (astro-ph/ ) 3

4 Spectroscopy of B1c: Outflow HCO+ 1-0 first moment Matthews, et al

5 Spectroscopy of B1c: Outflow/Core HCO+ 1-0 first moment N2H+ is destroyed along the outflow as predicted by models (i.e., Bergin et al. 1998) 5

6 Spectroscopy of B1c: Core 6

7 Spectroscopy of B1c: Rotation 2000 AU Age of 1.8 x 105 yr for a Galli & Shu type pseudodisk Kinematic age of the outflow ~ 5 x 104 yr for i=45º 7

8 Spectroscopy of B1c: Cavity JCMT beam N2H+ R~2500 AU N2H+, uniform weighting 2.7'' x 2.15'' beam (675 x 540 AU) Evaporated cavity, R~600 AU 8

9 SMA Observations: Evidence for Heating C18O 2-1 emission is unambiguously associated with the region of diminished N2H+ 1-0 emission SMA BIMA Doesn t peak at the position of the 3.3 mm continuum source. Matthews et al. in prep 9

10 Source Geometry of B1c heated grains ice mantles destroyed one consequence would be strong polarization signature within the cavity Matthews et al. 2006, in press 10

11 Polarization in the Cavity B1c discovered during 850 µm polarization observations No ostensible hole seen in 850 µm JCMT data Beam of 14'' 3500 AU Impossible to resolve cavity Matthews & Wilson

12 Polarization in the Cavity: SMA 4% 850 µm continuum peaks within the cavity Vectors are uniform in length within the cavity Could the heating of grains account for the high degree of polarization? Lai et al Data are consistent with this picture. 12

13 Spectral Energy Distribution Continuum modeling Envelope: 3.2 M Luminosity: 1.5 L Disk: 0.05 M 13

14 Summary of Barnard 1c to date Drives collimated, precessing outflow Continuum data show single peak at each wavelength observed N2H+ destroyed near star & along outflow Torus a remnant from destruction of N2H+? Atypical polarization signature Now seen in both single dish and interferometric maps Evaporation cavity may explain polarization signature (uniform vectors) Spectral Energy Distribution 1.5 L, 3000 K, 3.4 M envelope disk required to fit short wavelength data C18O 2-1 emission, 850 µm and 1.3 mm SMA emission (2-3'' resolution) peak within the N2H+ cavity 14

15 Current/Future Work JCMT high frequency observations scheduled with HARP-B (N2H+ 3-2) GBT/VLA NH3 observations to measure the variation in central temperature of B1c (some GBT data in hand) SMA polarimetry (increase S/N & extend beyond cavity) CARMA 1 mm observations CO mosaic 3.3 mm dust SOFIA 50 µm pol n 15

16 SMA Observations Matthews et al. in preparation 16

17 SMA Observations VLA SMA Other cores with evidence of heated cavities/missing N2H+ have not been mapped in polarized emission: e.g. L483-mm, IRAM , etc. Obvious targets for GB polarization survey. Matthews, Hogerheijde, Jorgensen & Bergin, 2006, ApJ, 653, in press 17

18 Polarization Holes NGC 2071 IR Cortes, Crutcher & Matthews (2006) 18