The Challenges of the Last Decade of Observations of PNe Gdansk June, 2005 Bruce Balick University of Washington HST image by Hans Van Winckel, and Martin Cohen Model by Vincent Icke

The Challenges of the Last Decade of Observations of PNe Introduction: In the past decade HST, Spitzer, and many other new tools have opened new ranges of spectral coverage and, at the same time, pushed the imaging observations to the milliarcsec domain. Introduction: In the past decade HST, Spitzer, and many other new tools have opened new ranges of spectral coverage and, at the same time, pushed the imaging observations to the milliarcsec domain. Gdansk June, 2005 Conclusion: The endpoint of stellar evolution is the startpoint for uncovering significant new insights into late stages of stellar evolution. Conclusion: The endpoint of stellar evolution is the startpoint for uncovering significant new insights into late stages of stellar evolution. Data: Observational progress has been dizzying. Data: Observational progress has been dizzying. Most theoreticians are just starting to recover. Most theoreticians are just starting to recover.

H-R Diagram, 1 M sun

1 solar mass, no rotation Sackman, Boothroyd & Kraemer 1993 Astrophysical Journal Inter- pulse Period = 10 5 y

Ascending the “AGB”; preparing to eject a protoPN Betelgeuse -

Round PNe from Isotropic Winds Kwok, Purton, & Fitzgerald 1978; Dyson, Pik’elner…

Challenge: If winds are Isotropic then why aren’t all PNe round? Gdansk June, 2005 ymmetries of PNe fall into clear patterns and categories. <20% are round. The other symmetries of PNe fall into clear patterns and categories. do almost all dying do almost all dying AGB/post AGB stars AGB/post AGB stars build collimators? build collimators? How? How?

Challenge. What paradigm? GISW models were generally successful in explaining the large-scale features of most PNe.

HST upended our complacency Gdansk June, 2005 Cat’s Eye NGC ” seeing [N II] [O III]

The devil is in the details… Jets FLIERs Paradigm lost?

Challenge: Why are many outflows stunningly collimated, esp pPNe? where there’s collimation, there must be collimators where there’s collimation, there must be collimators Kwok, Hrivnak, Su et al

He He He 2-90 CRL 618 Challenge: The disks are too thin! Q: Challenge: How do dying stars make disks without accretion? A: Mass-transfer binaries? Q: Challenge: Can accretion do it alone? What’s the collimator? A: At best, a thick disk.

Challenge: Too Many Axes, Not Enough Disks Sahai & Trauger 1998

CRL 2688 redshifted blueshifted Red = H  m Blue = scattered starlight Contours = 12 CO Red = H  m Blue = scattered starlight Contours = 12 CO Kastner et al 2001 Cox et al pairs!

Challenge: CO studies of outflows show HUGE momentum excess! Bujarrabal, Alcolea, and their collaborators: Bujarrabal, Alcolea, and their collaborators: radiation-driven winds aren’t a complete answer radiation-driven winds aren’t a complete answer Bujarrabal, Alcolea, and their collaborators: Bujarrabal, Alcolea, and their collaborators: radiation-driven winds aren’t a complete answer radiation-driven winds aren’t a complete answer name Mass M sol P = MV (gm cm s -1 ) E (erg) P/(L/c) CRL CRL M Frosty Leo > gravitational powering by close binaries?

NGC 6543 BD+30˚3639 NGC 7009 Ellipticals with Attitude: soft X rays fill the bubble

Challenge: Changing Wind Mode? NGC 6543 Corradi et al 2004

OH Alcolea et al. (2001) A&A 373,932 Challenge: “Hubble Flows”

Result: ages ≈ 5700 yr Corradi et al 2002 He2– 104

Menzel 3 Santander et al km s -1 Bottom line: all major components have nearly the same expansion ages. Bottom line: all major components have nearly the same expansion ages.

Challenge: Steady Winds or Eruptions? Physics of “Hubble” outflows: sudden ejection + ballistic flow? sudden ejection + ballistic flow? self similar? (adiabatic?) self similar? (adiabatic?) magnetic “event” (see Frank talk) magnetic “event” (see Frank talk) What processes orchestrate the What processes orchestrate the spectacular grand finale at the AGB tip? Whither all that outflow momentum? Whither all that outflow momentum?

Magnetized Wind Collimation Model Isodensity surfaces IRAS Kwok et al IRAS Kwok et al  Carinae Morse et al  Carinae Morse et al Steady magnetized wind carrying dipolar field. carrying dipolar field. Stellar rotation flings equatorial fields and flings equatorial fields and creates a (passive) disk creates a (passive) disk winds polar fields and winds polar fields and traps high-latitude winds traps high-latitude winds Steady state solution; can’t make Hubble flow can’t make Hubble flow Magnetic “bomb” next.

Grand Challenge: What creates and shapes PNe? Astronomy: How do stars create high- order symmetries in a brief event? Internal? Internal? Thermonuclear pulse? Thermonuclear pulse? Symmetry imposed by emerging B fields? Symmetry imposed by emerging B fields? External? External? Sudden CE phase or tidal onset? Sudden CE phase or tidal onset? What generates plural symmetry axes? What generates plural symmetry axes? Astronomy: How do stars create high- order symmetries in a brief event? Internal? Internal? Thermonuclear pulse? Thermonuclear pulse? Symmetry imposed by emerging B fields? Symmetry imposed by emerging B fields? External? External? Sudden CE phase or tidal onset? Sudden CE phase or tidal onset? What generates plural symmetry axes? What generates plural symmetry axes?

Applause

M2-9: 40 years of mischief

M2–9 HST motion picture

Common Envelope Collimator? Colors: Outflow Velocity Field Wire Frame: Isodensity Surface Colors: Outflow Velocity Field Wire Frame: Isodensity Surface F. Garcia, A.Frank, N. Soker, B. Balick, in progress

Magnetic fields, sudden Ionization & heating, steady winds Early MHD Simulation Model V, Garcia-Segura et al 1999 Astrophys J, 517, 767 Mz 3 Image Heuristic Model Mz 3 Image Heuristic Model

If we assume: M core = 0.5 M sun V esc = 1000 km/s M Egg ≈ M sun (Bujarrabal et al. 2001) R Egg ≈ 10 4 AU Some “al” #’s: Then: R core ≈ 0.2 R sun B core ≈ 10 5 Gauss KE core ≈ erg T spin-down ≈ 100 years Thompson, Hines, & Sahai (1997) ?? Magnetic “Bomb”: sudden emergence of surface B fields Frank, Matt & Balick (in progress)

“Discovery of Magnetic Fields in CPNs” Jordan, Werner, O’Toole, ASP Conf Ser (LANL Prerprints) ESO-VLT1 + FORS1 H  +HeII H  +HeII H  +HeII HeII 4686 NGC 1360 stellar circular polarization and models for 2832G (-1343, 1708, 2832, 194 G; 4 obs/42 days) LS1362 Abell 36? EGB 5? Whither the fields?

“Dynamos in AGB stars as the origin of magnetic fields shaping planetary nebulae” E.G. Blackman, A. Frank, J.A. Markiel, J.H. Thomas, H.M. van Horn Nature, 409, (25 January 2001) Wherefore the fields? … we show that an asymptotic-giant-branch (AGB) star can indeed generate a strong magnetic field, having as its origin a dynamo at the interface between the rapidly rotating core and the more slowly rotating envelope of the star. The fields are strong enough to shape the bipolar outflows that produce the observed bipolar planetary nebulae.

“A fossil origin for the magnetic field in A-stars and white dwarfs” J. Braithwaite and H.C. Spruit Nature, 431, (14 October 2004) Numerical simulations of the shape of the magnetic field lines in a magnetic star. Field lines protruding through the surface of the star (red) are held together and stabilized by the twisted ring inside the star (blue). This magnetic field configuration drifts slowly outward (over a period of hundreds of millions of years) under the influence of the finite electrical resistivity of the star, then distorts into the shape of the seam on a tennis ball. Wherefore the fields?