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INTERNAL KINEMATICS OF MICROSTRUCTURES AND IMPLICATIONS. Luis F. Miranda. IAA-CSIC. G. Anglada, R. Cesaroni, I. de Gregorio, J.F. Gómez, Y. Gómez, M.A. Guerrero, J.M. Torrelles, R. Vázquez. Precessing outflows Collimated ejections from binary central stars
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INTERNAL KINEMATICS OF MICROSTRUCTURES AND IMPLICATIONS Luis F. Miranda IAA-CSIC G. Anglada, R. Cesaroni, I. de Gregorio, J.F. Gómez, Y. Gómez, M.A. Guerrero, J.M. Torrelles, R. Vázquez • Precessing outflows • Collimated ejections from binary central stars • Water maser emission in planetary nebulae
NGC 6884 • Multi-component planetary nebula • Ellipsoidal shell • Point-symmetric spiral structures • Two bipolar knots The properties of the point-symmetric spirals agree that the spiral are precessing bipolar outflows Vexp ~ 55 kms-1 Precession period ~ 475 yr (D ~ 1.9 kpc, Palen et al. 2002) R=[NII] , G=H , B=[OIII] HST Miranda, Guerrero, Torrelles 1999
Hu2-1 and IC4846 IC4846 HHST Hu2-1 [NII]HST Binary central stars N The systemic velocity of the bipolar ejections does not coincide with the systemic velocity of the nebula Difference ~ 8 - 10 kms-1 Interpretation in terms of a binary star The velocity difference is related to the orbital velocity E 2" N E Vsys(jets) -Vsys(shell) = Vorb cos i cos 2" Orbital parameters Orbital separation < 30 AU Orbital period < 100 yr Related to symbiotic stars?
Water maser emission from red giants to planetary nebulae Typical emission from the (spherical) envelope of red giants and AGB stars (e.g. Elitzur 1992; Habing 1996; Engels 2002) W43A AGB star with a precessing bipolar jet (Imai et al. 2002) Detected in proto-planetary nebulae • IRAS 19296+2227 (Marvel & Boboltz 1998,1999) • IRAS 16342-3814 (Likkel & Morris 1988, Morris et al. 2003) • More cases Detected in extremely young planetary nebulae • K3-35 (Miranda et al. 2001) • IRAS 17347-3139 (de Gregorio et al. 2003)
K3-35 Bipolar planetary nebula (optical size ~ 10") with an equatorial torus [OI] [NII] [OI] Strong [NII] and [OIII] emission lines HeII 4686 Teff > 60000 K [NII] [SIII] HeI H [SII] Miranda et al. 2003 H HeII [OIII]
K3-35 • Water maser emission in a torus (r 85 AU [d = 5 kpc]) and at the tips of precessing collimated outflows ( 5000 AU from the center) • The jets are probably involved in the excitation of the distant water masers • The 1665 MHz line presents high levels of circular polarization (50%) magnetized torus (Miranda et al. 2001)
K3-35 New VLA observations reveal changes in the water maser spots Changes in region C No water maser at the tips of the jets (3 = 7 mJy) The time difference between the two epochs (2.5 yr) is too long to make a clear identification of the same water maser spots Proper motions (?) Destruction of the 1999 maser shell and creation of a new (2002) maser shell (?) + Miranda et al. 2001 ( September 1999) de Gregorio et al. 2003 (May 2002) 1.3cm continuum emission peak (de Gregorio et al. 2003)
IRAS 17347-3139 N • HST (K-band) (Bobrowsky et al. 1999) • Bipolar nebula 2" x 0.7" , PA -40º • Water maser emission detected with the Robledo 70 m antenna (Madrid) (de Gregorio et al. 2003, Survey for water maser emission in PNe) E 1" The radio continuun emission (1.3 cm-6 cm) indicates a partially optically thick ionized nebula (de Gregorio et al. 2003) Teff > 26000 °K ; Ne 106 cm-3 (D 0.8 kpc) Br and NeII nebular emission lines (Garcia-Lario, 2003, private communication)
IRAS 17347-3139 VLA observations 2002 +0.6 +1.3 • 13 water maser spots tracing an ellipse 0.25"0.12" (PA 62°) • If circular ring axis tilted 60° w.r.t. the observer • The kinematics suggests rotating and expanding motions in the ring • The 1.3cm continuum emission peak () does not coincide with the center of the ellipse • Inhomogenities in the (unresolved) ionized nebula + large beam? • Binary star? -0.7 0.0 +2 +2.6 -2.7 +3.3 +3.9 -3.3 -2.0 -1.3 -4.0 1" (De Gregorio et al. 2003)