Transcript
Probing Magnetic Fields in Protostars with near-IR Polarimetry
Barbara Whitney
University of Wisconsin-Madison
High-Resolution Observations (IRAS 04302+2247)
Data from Lucas & Roche (1997)
K-bandd = 140 pc0.3” resolution
Model for IRAS 04302+2247
Whitney & Wolff (2002)
K-bandd = 140 pc0.3” resolution
K-band polarization maps, no B-field
Pl = -6.9% PV = 0Integrated polarization:
Axial field (along z)
Pl = +2.7% PV = 0Integrated:
Whitney & Wolff 2002
Galli-Shu + toroid field
Bj = exp[-z/a](Br2 + Bq
2)1/2
V = 6%Pl = Q = -8%
Galli-Shu + toroid field
Integrated:
Galli-Shu + toroid field
Bj = exp[-z/a](b rcyl)-1.5 (Br2 + Bq
2)1/2
V = 3%Pl = Q = -16%
Galli-Shu + toroid field
Integrated: