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From the AGB to the PN phase with the PdBI. ccarrizo@iram.fr. Institut de Radio Astronomie Millimetrique (France). From the AGB to the PN phase with the Plateau de Bure Interferometer. Arancha Castro-Carrizo Jan Martin Winters Roberto Neri.
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From the AGB to the PN phase with the PdBI ccarrizo@iram.fr Institut de Radio Astronomie Millimetrique (France) From the AGB to the PN phase with the Plateau de Bure Interferometer Arancha Castro-Carrizo Jan Martin Winters Roberto Neri
Highest mm-site in the world, high atmospheric transparency. Winter 2005/2006, summer 2006 eastern track extension completed. 6 antenna of 15m in diameter 80 -115 GHz / 200 - 245 GHz Resolution: 0.5 arcs @ 1.3mm Sensitivity: 0.28 K in 1.6km/s @ 1.3mm Baselines extend up to 400 m Soon they will extend up to 800 m
Envelopes with marginal or no deviation from sphericity in the AGB phase, in contrast to the PPN stage where envelopes show strong asymmetries (bipolar, multipolar). Some sources observed by PdBI are presented in this HR diagram; they represent about a 30 per cent of all the (published) PdB data in this range. About 40 AGB stars mapped by PdBI (Neri et al. 1998) From a total of 35 PPNe emitting in CO: 17 already mapped by PdBI 8 not observable by PdBI (low-dec) 4 no (or very weak) wings in the CO profiles 6 weak and/or low-quality CO spectra
TT Cyg geometrically thin, no evidence for gas in and outside the shell, binary system, small clumps, one or two wind models, SHELL 2 has a different mass loss history (lower mass rate 1e-8 and mass), SHELL 1 (1000x larger rate). TT Cyg, U Cam and S Sct have all detached shells detected in CO emission, though of different dynamical ages (10000 S Sct, 5000 U Cam). SHELL 2 CLUMP SHELL 1 PDBI 12CO(1-0) TT Cyg 35” = 7000 yr D = 510 pc Olofsson et al. (2000) A&A, 353, 383
TT Cyg. Models reproduce this copious episodic mass loss process, for stars with lower initial mass SHELL 2 CLUMP • t = 800yr • M = 0.008M0 Mi = 1.1M0 8 x 10-6 6 x 10-6 M [M0/yr] . 4 x 10-6 SHELL 1 TT Cyg 2 x 10-6 Schroder, Winters & Sedlmayr (1999), A&A 349, 898 PDBI 12CO(1-0) TT Cyg 35” = 7000 yr D = 510 pc Olofsson et al. (2000) A&A, 353, 383
IRC+10216 arcs. Concentric arcs and rings give evidence for modulated mass loss, just detected in the optical in other objects, but only in IRC10216 in a few molecular transitions; underlying mechanism not yet understood IRC+10216 PDBI CN(2-1) CFHT V-BAND DUST 15” = 400 yr D = 80 pc Mauron & Huggins (1999) A&A, 315, 284 Guélin et al. (2000) IAU Symp 197, 365
M1-92. Molecular emission for the different velocity channels. Bipolar nebula. Lobes present empty holes inside, where a high-excitation region is detected in the optical. A massive disk, contained in the equatorial plane, seems to be the undisrupted remnant of the previous AGB envelope. Note the high-velocity molecular clumps that seem to escape through the breakthrough seen in the optical M1-92 PDBI 13CO(2-1) HST WFPC2 6300 A BREAKTHROUGH 10000 AU = 4” BREAKTHROUGH Bujarrabal et al. (1998) ApJ, 504, 915 Bujarrabal et al. (1998) A&A, 331, 361
M2-56. Tiny bipolar nebula in the optical (weaker emission is detected also farther). The molecular envelope is however not tiny, but extends up to 27 arcsec PdBI average map of the 12CO(2-1) emission Castro-Carrizo et al. (2002) A&A 386, 633 M 2-56 HST image (Ha+continuum) by Trammell & Goodrich (1998) AAS 193, 1403
M2-56, maps and model. More in detail; CO shows also a bipolar nebula, in which probably part of the lobes have been photo-dissociated. M 2-56 12CO(2-1) 10 North offset (arc.sec.) 0 -10 20 10 0 -10 -20 East offset (arc.sec.) Castro-Carrizo et al. (2002) A&A 386, 633
M2-9, CO vs. optical. Only a disk perpendicular to the bipolar optical nebula has been detected in CO; it seems to be the remnant of the previous AGB envelope. Optical [NII] line emission (grey scale) by Balick et al. (1987) AJ 94, 671 12CO(1-0) emission (contours) at the systemic velocity, by Zweigle et al. (1997) A&A 324, 624 M 2-9 12CO(1-0)
IRAS17436+5003, jets are still inside the previous AGB envelope. High sensitivity data. mm-interferometry shows us what is happening inside the spherical envelopes that were created in the AGB phase, so the seed of the future nebular asymmetry IRAS 17436+5003 12CO(2-1) Alcolea et al. (2003) A&A in prep
CRL618, very fast jets still inside the previous AGB envelope. Clumpy structure in jets, double shell, tentative minor jet2. PdB maps also of other molecules: hco+,hc3n,h41a,ch3cn. The radio recombination line H41a coming from the inner 2arcsec region presents some bumps over its gaussian profile; an example of other kind of data (different to molecular emission) that are obtained by PdBI Neri et al. (2003) in prep. H41a 14.7 km/s JET2 ? DOUBLE SHELL JET1 N E Castro-Carrizo et al. (2003) in prep. AFGL 618 PDBI 12CO(2-1)
Frosty Leo. Present information: multiple-jet features in the optical, large amount of gas accelerated in the post-AGB phase (CO) Multiple and complex substructures Frosty Leo HST image at 0.6um Main ejection + multiple (apparently) minor jets Sahai et al. (2000) A&A 360, L9
Frosty Leo, CO maps show bipolar nebula. Its symmetry axis seems to coincide with the (apparently) minor jet detected in the optical. Frosty Leo 12CO(2-1) Castro-Carrizo et al. (2003), in prep.
Frosty Leo, more in detail. The central velocity channels present a complex compact structure that seems to be the result of several ejections; probably a first one, that shaped the optical nebula (about 3000 yr ago), and (at least) a second one that now we detect in CO (that probably took place about 1500 yr ago). Note that the central disk reaches velocities as high as 30km/s; it is not therefore the undisrupted remnant of the previous AGB envelope 12CO(2-1) Castro-Carrizo et al. (2003), in prep. Frosty Leo
Some conclusions, and a look at the future To conclude … mm interferometry unveils details in the innermost C.E. More sensitivity and resolution is needed to improve and enlarge our sample of envelopes with rings/arcs in molecular tracers High-sensitivity mm interferometry necessary to discriminate between physical models associated with the generation of winds and structures in C.E. Plateau de Bure is ready, with much better resolution and sensitivity!! - to investigate the molecular distribution in envelopes with known concentric rings, in order to discriminate between chemical and dynamical models - to investigate the mass loss rate evolution, the clumpiness and the departures from spherical symmetry in AGB envelopes Plateau de Bure will be ready in future!! - to study polarization, so magnetic activity, in the innermost region - to observe molecular transitions at 2mm and 0.8mm (0.2”)
Others: Hyper-giants with massive molecular envelopes, are they particular PPNe? Hypergiants; the case of AFGL 2343 and IRC+10420 They present very massive spherical circumstellar envelopes Particular PPNe ? Thermal SiO emission coming from a detached shell !! Special excitation conditions?, chemistry?, spherical shocks? Castro-Carrizo et al. (2001) A&A 368, L34 Castro-Carrizo et al. in prep.
Others: OH231.8 presented by J. Alcolea. Note also the PdB data obtained, for example, in CRL2688, presented by P.Cox with multiple jet structure, and the first rotational disk detected in the Red Rectangle by V.Bujarrabal et al. OH 231.8+4.2 Alcolea et al. (2001) A&A 373,932