Miras, mass loss, and the origin of planetary nebulae

Author(s):

L. A. Willson

Keyword(s):

Mass Loss ◽

Fundamental Mode ◽

Planetary Nebulae ◽

Asymptotic Giant Branch ◽

Mira Variables ◽

Moderate Mass

Mira variables are found at the tip of the asymptotic giant branch, with L≈3000-5000Lʘ and TeH3000K. (Feast 1981; Willson 1981a). They are fundamental mode pulsators (Willson 1979, 1981a). A typical Mira has P~350 days, R~200-300Rʘ, M~1-2Mʘ (Willson 1979; 1981a). From the atmospheric velocities of the Miras plus a fundamental mode period-massradius relation one finds present masses for the Miras which are not very different from their progenitor masses (Willson 1981a). This suggests that pre-Mira mass loss is moderate -- ≲20% of the mass is lost before pulsation starts. In fact one expects only moderate mass loss before the Mira stage;

Evolutionary Tracks for Central Stars of Planetary Nebulae

10.1017/s0074180900139038 ◽

1989 ◽

Vol 131 ◽

pp. 463-472 ◽

Cited By ~ 12

Author(s):

Detlef Schönberner

Keyword(s):

Mass Loss ◽

White Dwarf ◽

Planetary Nebulae ◽

Asymptotic Giant Branch ◽

Helium Burning ◽

Hydrogen Burning ◽

Stellar Envelope ◽

Thermal Pulse ◽

Pulse Cycle ◽

Central Stars

Our understanding of the evolution of Central Stars of Planetary Nebulae (CPN) has made considerable progress during the last years. This was possible since consistent computations through the asymptotic giant branch (AGB), with thermal pulses and (in some cases) mass loss taken into account, became available (Schönberner, 1979, 1983; Kovetz and Harpaz, 1981; Harpaz and Kovetz, 1981; Iben, 1982, 1984; Wood and Faulkner, 1986). It turned out that the evolution depends very sensitively on the inital conditions on the AGB. More precisely, the evolution of an AGB remnant is a function of the phase of the thermal-pulse cycle during which this remnant was created on the tip of the AGB by the planetary-nebula (PN) formation process (Iben, 1984, 1987). This was first shown by Schönberner (1979), and then fully explored by Iben (1984). In short, two major modes of PAGB evolution to the white dwarf stage are possible, according to the two main phases of a thermally pulsing AGB star: the hydrogen-burning or helium-burning mode. If, for instance, the PN formation, i.e. the removal of the stellar envelope by mass loss, happens during a luminosity peak that follows a thermal pulse of the helium-burning shell, the remnant leaves the AGB while still burning helium as the main energy supplier (Härm and Schwarzschild, 1975). On the other hand, PN formation may also occur during the quiescent hydrogen-burning phase on the AGB, and the remnant continues then to burn mainly hydrogen on its way to becoming a white dwarf.

Stellar wind models of central stars of planetary nebulae

Astronomy and Astrophysics ◽

10.1051/0004-6361/201937150 ◽

2020 ◽

Vol 635 ◽

pp. A173 ◽

Author(s):

J. Krtička ◽

J. Kubát ◽

I. Krtičková

Keyword(s):

Mass Loss ◽

White Dwarf ◽

Planetary Nebula ◽

Loss Rate ◽

Mass Loss Rate ◽

Planetary Nebulae ◽

Terminal Velocity ◽

Asymptotic Giant Branch ◽

Central Stars ◽

Loss Rates

Context. Fast line-driven stellar winds play an important role in the evolution of planetary nebulae, even though they are relatively weak. Aims. We provide global (unified) hot star wind models of central stars of planetary nebulae. The models predict wind structure including the mass-loss rates, terminal velocities, and emergent fluxes from basic stellar parameters. Methods. We applied our wind code for parameters corresponding to evolutionary stages between the asymptotic giant branch and white dwarf phases for a star with a final mass of 0.569 M⊙. We study the influence of metallicity and wind inhomogeneities (clumping) on the wind properties. Results. Line-driven winds appear very early after the star leaves the asymptotic giant branch (at the latest for Teff ≈ 10 kK) and fade away at the white dwarf cooling track (below Teff = 105 kK). Their mass-loss rate mostly scales with the stellar luminosity and, consequently, the mass-loss rate only varies slightly during the transition from the red to the blue part of the Hertzsprung–Russell diagram. There are the following two exceptions to the monotonic behavior: a bistability jump at around 20 kK, where the mass-loss rate decreases by a factor of a few (during evolution) due to a change in iron ionization, and an additional maximum at about Teff = 40−50 kK. On the other hand, the terminal velocity increases from about a few hundreds of km s−1 to a few thousands of km s−1 during the transition as a result of stellar radius decrease. The wind terminal velocity also significantly increases at the bistability jump. Derived wind parameters reasonably agree with observations. The effect of clumping is stronger at the hot side of the bistability jump than at the cool side. Conclusions. Derived fits to wind parameters can be used in evolutionary models and in studies of planetary nebula formation. A predicted bistability jump in mass-loss rates can cause the appearance of an additional shell of planetary nebula.

Structure and Evolution of Planetary Nebula Haloes

10.1017/s0074180900209297 ◽

2003 ◽

Vol 209 ◽

pp. 439-446 ◽

Author(s):

Matthias Steffen ◽

Detlef Schönberner

Keyword(s):

Mass Loss ◽

Numerical Simulations ◽

Stellar Evolution ◽

Planetary Nebula ◽

Previous History ◽

Planetary Nebulae ◽

Asymptotic Giant Branch ◽

Time Dependent ◽

Density Structure ◽

History Of

The density structure of the extended haloes of Planetary Nebulae (PN) is generally believed to reflect the previous history of heavy mass loss during the final stages of stellar evolution on the asymptotic giant-branch (AGB). In this review, we discuss different interpretations of the observed PN halo structures in the light of recent numerical simulations combining detailed AGB and post-AGB stellar evolution calculations with time-dependent hydrodynamical wind models.

Progenitors of Planetary Nebulae

10.1017/s007418090013880x ◽

1989 ◽

Vol 131 ◽

pp. 401-410 ◽

Author(s):

Sun Kwok

Keyword(s):

Mass Loss ◽

Significant Role ◽

Planetary Nebulae ◽

Central Star ◽

Asymptotic Giant Branch ◽

The Past

Over the past decade, we have come to realize that mass loss on the asymptotic giant branch (AGB) plays a significant role in the formation of planetary nebulae (PN). Mass ejected during the AGB can now be observed in haloes of PN and we believe that the main shell of PN is formed by the interaction of this material with a later-developed central-star wind. In this review, we show that the evolution from AGB to PN can be traced in a continuous infrared sequence. This sequence predicts properties of proto-PN which allow them to be identified.

The IAC morphological catalog of Northern Galactic Planetary Nebulae

10.1017/s0074180900129730 ◽

1997 ◽

Vol 180 ◽

pp. 24-25 ◽

Cited By ~ 3

Author(s):

A. Manchado ◽

M. A. Guerrero ◽

L. Stanghellini ◽

M. Serra-Ricart

Keyword(s):

Magnetic Fields ◽

Mass Loss ◽

Stellar Evolution ◽

Morphological Study ◽

Planetary Nebulae ◽

Asymptotic Giant Branch ◽

Intermediate Mass ◽

Evolutionary Scheme ◽

Late Stages

Planetary Nebulae (PNs) are highly representative of the late stages of intermediate mass stellar evolution. However, there are still many unresolved questions in their evolutionary scheme. Mass loss processes during the Asymptotic Giant Branch (AGB) are not fully understood. Binarity, rotation and magnetic fields may play an important role in PNs formation. The morphological study of PNs will help us to address those questions, and therefore a meaningful homogeneous database is needed.

Maser emission in planetary nebulae

Proceedings of the International Astronomical Union ◽

10.1017/s1743921307013154 ◽

2007 ◽

Vol 3 (S242) ◽

pp. 292-298 ◽

Author(s):

Yolanda Gómez

Keyword(s):

Water Vapor ◽

Mass Loss ◽

Planetary Nebula ◽

Planetary Nebulae ◽

Central Star ◽

Asymptotic Giant Branch ◽

Kinematic Modeling ◽

Maser Emission ◽

The Core ◽

Unambiguous Detection

AbstractStars at the top of the asymptotic giant branch (AGB) can exhibit maser emission from molecules like SiO, H2O and OH. These masers appear in general stratified in the envelope, with the SiO masers close to the central star and the OH masers farther out in the envelope. As the star evolves to the planetary nebula (PN) phase, mass-loss stops and ionization of the envelope begins, making the masers disappear progressively. The OH masers in PNe can be present in the envelope for periods of ~1000 years but the H2O masers can survive only hundreds of years. Then, H2O maser emission is not expected in PNe and its detection suggests that these objects are in a very particular moment of its evolution in the transition from AGB to PNe. We discuss the unambiguous detection of H2O maser emission in two planetary nebulae: K 3-35 and IRAS 17347-3139. The water-vapor masers in these PNe are tracing disk-like structures around the core and in the case of K3-35 the masers were also found at the tip of its bipolar lobes. Kinematic modeling of the H2O masers in both PNe suggest the existence of a rotating and expanding disk. Both PNe exhibit a bipolar morphology and in the particular case of K 3-35 the OH masers are highly polarized close to the core in a disk-like structure. All these observational results are consistent with the models where rotation and magnetic fields have been proposed to explain the asymmetries observed in planetary nebulae.

Measuring Mass-Loss Evolution at the Tip of the Asymptotic Giant Branch

Publications of the Astronomical Society of Australia ◽

10.1071/as09032 ◽

2010 ◽

Vol 27 (2) ◽

pp. 214-219 ◽

Cited By ~ 4

Author(s):

C. Sandin ◽

M. M. Roth ◽

D. Schönberner

Keyword(s):

Mass Loss ◽

Galactic Disk ◽

Planetary Nebulae ◽

Asymptotic Giant Branch ◽

High Mass ◽

Stellar Winds ◽

Circumstellar Envelope ◽

Stellar Envelope ◽

Stellar Properties ◽

Loss Rates

AbstractIn the final stages of stellar evolution low- to intermediate-mass stars lose their envelope in increasingly massive stellar winds. Such winds affect the interstellar medium and the galactic chemical evolution as well as the circumstellar envelope where planetary nebulae form subsequently. Characteristics of this mass loss depend on both stellar properties and properties of gas and dust in the wind formation region. In this paper we present an approach towards studies of mass loss using both observations and models, focussing on the stage where the stellar envelope is nearly empty of mass. In a recent study we measure the mass-loss evolution, and other properties, of four planetary nebulae in the Galactic disk. Specifically we use the method of integral field spectroscopy on faint halos, which are found outside the much brighter central parts of a planetary nebula. We begin with a brief comparison between our and other observational methods to determine mass-loss rates in order to illustrate how they differ and complement each other. An advantage of our method is that it measures the gas component directly requiring no assumptions of properties of dust in the wind. Thereafter we present our observational approach in more detail in terms of its validity and its assumptions. In the second part of this paper we discuss capabilities and assumptions of current models of stellar winds. We propose and discuss improvements to such models that will allow meaningful comparisons with our observations. Currently the physically most complete models include too little mass in the model domain to permit a formation of winds with as high mass-loss rates as our observations show.

IRAS Observations of Symbiotic Stars

International Astronomical Union Colloquium ◽

10.1017/s0252921100063405 ◽

1989 ◽

Vol 106 ◽

pp. 391-400 ◽

Author(s):

M. Parthasarathy ◽

H.C. Bhatt

Keyword(s):

Mass Loss ◽

Loss Rate ◽

Mass Loss Rate ◽

Planetary Nebulae ◽

Evolutionary Stage ◽

Symbiotic Stars ◽

Late Type ◽

Mira Variables ◽

Show Evidence ◽

The Masses

AbstractOf the 129 symbiotic stars in Allen's (1984) catalogue, 42 were found to be IRAS sources. Of these 42 IRAS sources, 22 are D-type (symbiotic Miras), 5 are D'-type (yellow symbiotics) and 15 are S-type. The separation of S, D and D’ types into three distinct groups is clearer in the log[fλ(25μm)/fλ(12μm)] versus (H-K) diagram. The IRAS fluxes of S-type symbiotics are consistent with that observed from normal M giants. This result suggests that mass-loss rate from most of the S-type symbiotics is similar to that from normal M giants. The IRAS data of D-type symbiotics shows evidence for the presence of dust envelopes. The masses of the dust envelopes (10-6 to 10-7 Mo) around Miras in D-type symbiotics are similar to that observed in field Mira variables. These results suggest that mass-loss rates in symbiotic Miras are similar to those from field Mira variables and also that the mass loss from symbiotic Miras is pulsationally driven similar to that found in field Mira variables by Whitelock, Pottasch and Feast (1987). Analysis of IRAS data of yellow symbiotics Ml-2, AS201, Cnl-1, Wray 157. and HD149427 suggests that they are young planetary nebulae containing a binary nucleus. Ml-2, AS201 and Cnl-1 show evidence for the presence of evolved hot companions. The evolutionary stage of the late type (F-G) companions is not clear.

Multiple shell Planetary Nebulae: Evolutionary paths and observed configurations

10.1017/s0074180900131158 ◽

1997 ◽

Vol 180 ◽

pp. 319-324

Author(s):

Letizia Stanghellini

Keyword(s):

Mass Loss ◽

Planetary Nebulae ◽

Asymptotic Giant Branch ◽

Evolutionary Paths ◽

Central Stars

Recent observations of multiple shell planetary nebulae confirm the existing subdivision into two morphological types: attached halo and detached halo. The multiple shell phenomenon appears in about twenty-five percent of round and elliptical planetary nebulae of the Instituto de Astrofisica de Canarias morphological survey. The analysis of these nebulae together with that of their central stars lead to the interpretation that detached halo nebulae are formed through discontinuous mass loss at the Asymptotic Giant Branch tip. The attached halo nebulae, instead, are probably produced via dynamical nebular shaping.

Planets, Planetary Nebulae, and Intermediate Luminosity Optical Transients (ILOTs)

10.20944/preprints201804.0212.v1 ◽

2018 ◽

Author(s):

Noam Soker

Keyword(s):

Mass Loss ◽

Loss Rate ◽

Main Sequence ◽

Mass Loss Rate ◽

Planetary Nebulae ◽

Gravitational Energy ◽

Asymptotic Giant Branch ◽

Main Sequence Star ◽

Low Mass ◽

Optical Transient

I review some aspects related to the influence of planets on the evolution of stars before and beyond the main sequence. Some processes include the tidal destruction of a planet on to a very young main sequence star, on to a low mass main sequence star, and on to a brown dwarf. This process releases gravitational energy that might be observed as a faint intermediate luminosity optical transient (ILOT) event. I then summarize the view that some elliptical planetary nebulae are shaped by planets. When the planet interacts with a low mass upper asymptotic giant branch (AGB) star it both enhances the mass loss rate and shapes the wind to form an elliptical planetary nebula, mainly by spinning up the envelope and by exciting waves in the envelope. If no interaction with a companion, stellar or sub-stellar, takes place beyond the main sequence, the star is termed a Jsolated star, and its mass loss rates on the giant branches are likely to be much lower than what is traditionally assumed.