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Resolved Inner Disks around Herbig Ae/Be Stars: Near-IR Interferometry with PTI. Josh Eisner Collaborators: Ben Lane, Lynne Hillenbrand, Rachel Akeson, and Anneila Sargent. Eisner et al. 2003, ApJ, 598, 1341 Eisner et al. 2004, ApJ, submitted. Ringberg Castle, 2004. Circumstellar Disks.
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Resolved Inner Disks around Herbig Ae/Be Stars: Near-IR Interferometry with PTI Josh Eisner Collaborators: Ben Lane, Lynne Hillenbrand, Rachel Akeson, and Anneila Sargent • Eisner et al. 2003, ApJ, 598, 1341 • Eisner et al. 2004, ApJ, submitted Ringberg Castle, 2004
Circumstellar Disks • Disks linked to star and planet-formation • Accretion mechanism: IMF, stellar rotation, magnetic properties, outflows • Disk properties (e.g., temperature, density, geometry) dictate planetary properties • Relation to proto-solar nebula Artist’s conception of TW Hya Disk
Herbig Ae/Be stars: • Higher-mass analog of T Tauris: 2-10 M • Emission lines,variability, excess IR and mm emission • SED models: thin accretion disks (Hillenbrand et al. 1992), flared disks (Chiang & Goldreich 1997), puffed up inner disk walls (Dullemond et al. 2001) • Forbidden emission lines (Corcoran & Ray 1997) • Ha spectropolarimetry (Vink et al. 2002) • Resolved mm emission: flattened structures on 100 AU scales with Keplerian rotation • Strong evidence from new near-IR interferometry • Herbig Ae/Be stars: • Higher-mass analog of T Tauris: 2-10 M • Emission lines,variability, excess IR and mm emission • SED models: thin accretion disks (Hillenbrand et al. 1992), flared disks (Chiang & Goldreich 1997), puffed up inner disk walls (Dullemond et al. 2001) • Forbidden emission lines (Corcoran & Ray 1997) • Ha spectropolarimetry (Vink et al. 2002) • Resolved mm emission: flattened structures on 100 AU scales with Keplerian rotation • Strong evidence from new near-IR interferometry • Herbig Ae/Be stars: • Higher-mass analog of T Tauris: 2-10 M • Emission lines,variability, excess IR and mm emission • SED models: thin accretion disks (Hillenbrand et al. 1992), flared disks (Chiang & Goldreich 1997), puffed up inner disk walls (Dullemond et al. 2001) • Forbidden emission lines (Corcoran & Ray 1997) • Ha spectropolarimetry (Vink et al. 2002) • Resolved mm emission: flattened structures on 100 AU scales with Keplerian rotation • Strong evidence from new near-IR interferometry • Herbig Ae/Be stars: • Higher-mass analog of T Tauris: 2-10 M • Emission lines,variability, excess IR and mm emission • SED models: thin accretion disks (Hillenbrand et al. 1992), flared disks (Chiang & Goldreich 1997), puffed up inner disk walls (Dullemond et al. 2001) • Forbidden emission lines (Corcoran & Ray 1997) • Ha spectropolarimetry (Vink et al. 2002) • Resolved mm emission: flattened structures on 100 AU scales with Keplerian rotation • Strong evidence from new near-IR interferometry • Herbig Ae/Be stars: • Higher-mass analog of T Tauris: 2-10 M • Emission lines,variability, excess IR and mm emission • SED models: thin accretion disks (Hillenbrand et al. 1992), flared disks (Chiang & Goldreich 1997), puffed up inner disk walls (Dullemond et al. 2001) • Forbidden emission lines (Corcoran & Ray 1997) • Ha spectropolarimetry (Vink et al. 2002) • Resolved mm emission: flattened structures on 100 AU scales with Keplerian rotation • Strong evidence from new near-IR interferometry … < 0.1-1 AU (Dullemond, Dominik, & Natta 2001) (Vink et al. 2002) (Corcoran & Ray 1997) (Mannings & Sargent 1997) Disks Around HAEBEs • Herbig Ae/Be stars: • Higher-mass analog of T Tauris: 2-10 M • Emission lines,variability, excess IR and mm emission • SED models: thin accretion disks (Hillenbrand et al. 1992), flared disks (Chiang & Goldreich 1997), puffed up inner disk walls (Dullemond et al. 2001) • Forbidden emission lines (Corcoran & Ray 1997) • Ha spectropolarimetry (Vink et al. 2002) • Resolved mm emission: flattened structures on 100 AU scales with Keplerian rotation • Strong evidence from new near-IR interferometry
Ds amplitude delay Palomar Testbed Interferometer (PTI) • PTI observations allow large sample, good uv coverage • longer baselines facilitate detection of asymmetry • PTI components: • 3 telescopes each 0.4 m • 110 m NS oriented 20º E of N (4 mas) • 85 m NW oriented 81º E of N (5 mas) • 87 m SW baseline recently operational! • two apertures (A1,A2), delay lines (DL), beam combiner (BC), single-mode fiber (SMF), detector s DL A2 BC A1 SMF Detector DL B
System visibility from unresolved calibrators Ds amplitude delay Fringe Measurement: V2 Sky U-V • I1 ~ e-ik d1 e-iwt ; I2 ~ e-k d2 e-iks•B e-iwt;IC = I1 + I2 • P = <IC*IC> = 2+2cos(k [s•B+d1-d2]) • Fringe Spacing: Ds = l/B (~5 mas for PTI) • Visibilities: V(u,v) = ∫ dx dy A(x,y) F(x,y) e-2pi(ux+vy) • u = Bx/l ; v = By/l • V is the FT of brightness distribution (van Cittert-Zernike theorem) • IFT: F(x,y) A(x,y) = ∫ du dv V(u,v) e2pi(ux+vy) • PTI measures normalized V2
PTI Observations of HAEBEs • 2.2 mm observations of 14 HAEBEs SpTyp ~ O9-F0; d~100-1000 pc • Fit models to PTI visibilities: uniform disk, Gaussian, ring, accretion disk with hole, flared disk with puffed-up inner wall (+star) • All but 2 sources (HD141569, HD158352) resolved; angular sizes ~1-6 mas. • Inclinations: • MWC 480, MWC 758, CQ Tau, VV Ser, V1685Cyg, AS 442, MWC 1080 inclined • AB Aur nearly face-on • V1295 Aql, T Ori, MWC 297 unknown • Puffed-up inner disk inconsistent for earliest spectral types: MWC 297, V1685 Cyg, MWC 1080 uv sky
PTI+IOTA Data • Some of our sample also observed by IOTA (Millan-Gabet, Schloerb, & Traub 2001) • K-band: AB Aur, MWC 1080 • H-band: AB Aur, T Ori, MWC 297, V1295 Aql, V1686 Cyg, MWC 1080 • Shorter baselines than PTI (20-40m vs. 85-110m)additional constraints on geometry • Larger FOV than PTI (3˝ vs 1˝) constrains incoherent emission from extended dust
SEDs • Inner radius, inclination from PTI data; provide inputs for SED modeling. Can probe large range of disk radii, constrain parameters including temperature, overall geometry, mass) • SEDs compiled from new JHK PALAO data and the literature (stellar params from published spec type & BVRI photometry) • 2 models: • geometrically thin accretion disks w/ inner holes • flared 2-layer disks w/ puffed-up inner walls Trim, Tint, Tsurf Parameters: Rin, i, Tin,Rout,b, S, kn T(R) R-3/4 Parameters: Rin,i, Tin (Rout)
Flared Passive Disks with Puffed-Up Inner Walls Geometrically Flat Accretion Disks
Inner Disk Vertical Structure • For later-type HAEBEs, puffed-up inner disk models better • Early-types are fit well by flat disk models; not at all by puffed-up inner walls • Different accretion mechanism? Puffed-Up Inner Disks Flat Inner Disks
Inner vs. Outer Disks: Warping? PTI near-IR: i ≈ 10-20 Millimeter: i ≈ 76 Mannings & Sargent 1997
Summary • PTI observations of 14 HAEBEs: 12 resolved (1-6 mas), ≥7 significantly inclined • No significant mis-alignment of inner and outer disks • Different vertical disk structure for early and late spectral types • Flat accretion disks better for early-types • Flared disks w/ puffed-up inner walls for later types • Magnetospheric accretion in HAes vs. Equatorial accretion in HBes?