CDROM/APJS/V92/P125 Post-AGB Evolution (Vassiliadis & Wood 1994) ================================================================================ Post-Asymptotic Giant Branch Evolution of Low- to Intermediate-Mass Stars E. Vassiliadis & P.R. Wood <1994, ApJS, 92, 125> =1994ApJS...92..125V ================================================================================ Abstract: In this paper, we present the results for the post-AGB phases of stellar evolutionary sequences, complete from the main-sequence phase, through the AGB phase, and on into the planetary nebula and white dwarf regimes. Mass loss has been included using an empirical formalism derived from observed mass-loss rates of planetary nebula nuclei available in the literature and from radiation-pressure-driven stellar wind theory. Models are calculated for initial masses 0.89, 0.95, 1.0, 1.5, 2.0, 2.5, 3.5, and 5.0 Msun, and metallicities 0.016, 0.008, 0.004, and 0.001. These abundance and mass values were chosen to allow comparison with Galactic, and Magellanic Cloud planetary nebulae and their nuclei. The post-AGB evolutionary sequences fall into two distinct groups depending on when the planetary nebula nuclei leave the AGB: one group where helium-shell burning is dominant, and the other group where hydrogen-shell burning is dominant. Of the 27 computed sequences: 17 are hydrogen-burners, and 10 are helium- burners. In only five cases was any effort made to control the phase of departure from the AGB. Lower mass models are more likely to leave the AGB burning helium, as the preceding AGB evolution has a mass-loss rate which is greatest immediately prior to a helium-shell flash. The calculations are compared with the large observational database that has developed over recent years for the Large Magellanic Cloud. These calculations will be useful for determining the planetary nebula luminosity function, and for the study of the ultraviolet excess observed in elliptical galaxies. Keywords: Magellanic Clouds -- planetary nebulae: general -- stars: evolution -- stars: interiors Description: The evolutionary tracks in Tables 3, 4, and 5 all follow the same basic format. Each track is preceded by an indication of its initial, main-sequence mass, M, and its metallicity, Z, for example: (M,Y,Z)=(1.0,0.25,0.016) (The index Y is 0.25 for every track.) The time, log Teff, and log L/Lsun then follows in a series of records. The end of the track is indicated by a blank line, and then the next track begins. Note that this format is incompatible with the Flexible Image Transport System ASCII table standard, and as such, these data can not be used to generate valid FITS tables. File Summary: -------------------------------------------------------------------------------- File Name Lrecl Records Explanations -------------------------------------------------------------------------------- table3.dat 25 754 H-Burning PNN Evolutionary Models table4.dat 25 419 He-Burning PNN Evolutionary Models table5.dat 25 46 H-Like He-Burning PNN Evolutionary Model table.tex 87 1014 LaTeX version of tables 3, 4, and 5 -------------------------------------------------------------------------------- Byte-by-byte Description of file: table3.dat, table4.dat, and table5.dat Header record for each track -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 9 9X --- --- '(M,Y,Z)=(' 10-13 F4.2 Msun M Initial, main-sequence mass 14-19 6X --- --- ',0.25,' Y index is always 0.25 20-24 F5.3 --- Z Metallicity 25 1X --- --- ')' -------------------------------------------------------------------------------- Byte-by-byte Description of file: table3.dat, table4.dat, and table5.dat Data records for each track (a blank line indicates the end of the track) -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1-10 F10.1 yr Time Time. Taken to be zero at log Teff = 4. 11-17 F7.3 --- Teff log Teff 18-25 F8.3 --- L log L/Lsun -------------------------------------------------------------------------------- ================================================================================ (End) Lee Brotzman [ADS] 12-May-94