Interpolated PARSEC Stellar Evolution Tracks by philrosenfield

Download Interpolated PARSEC Tracks

PARSEC V1.2S Tracks were downloaded Jan 2016 from Alessandro Bressan's Home Page

For isochrones please use Leo Girardi's web interface

Tracks were run using parsec2match.py on 2016-02-02 11:05:27 (git hash ab24083).

Download all tracks: All Tracks

Or download individual metallicity sets: Z=0.0001 Y=0.249, Z=0.0002 Y=0.249, Z=0.0005 Y=0.249, Z=0.001 Y=0.250, Z=0.002 Y=0.252, Z=0.004 Y=0.256, Z=0.006 Y=0.259, Z=0.008 Y=0.263, Z=0.01 Y=0.267, Z=0.014 Y=0.273, Z=0.017 Y=0.279, Z=0.02 Y=0.284, Z=0.03 Y=0.302, Z=0.04 Y=0.321, Z=0.06 Y=0.356

Track Interpolations

PARSEC tracks are interpolated such that each track has the same number of points between each equivalent evolutionary point (EEP).

Complete details are in the codebase, a good starting point is define_eep.py.

Model number*	EEP Notes
0	Beginning of Pre Main Sequence
80	Minimum of Pre Main Sequence
160	End of Pre-Main Sequence
240	Beginning of Main Sequence (MS): Starting of the central H-burning. For M > 20 Msun: `log L` minimum after end of PMS.
439	`log Teff` minimum on the Main Sequence. Calculated one of four possible ways: First minimum in `log Teff` For no minimum in `log Teff` (M>50 Msun, usually >100), halfway in age between MS beginning and MS Turn off `XCEN=0.30` for low-mass stars (via BaSTi) For very low mass stars that never reach `XCEN=0.30` half the age of the universe ~= 13.7/2 Gyr
539	Main Sequence turn off (MSTO): `log Teff` maximum along the MS. For very low mass stars that never reach the MSTO: the age of the universe ~= 13.7 Gyr
639	Maximum luminosity of the sub-giant phase: Maximum in `log L` for high-mass or `XCEN=0.0` for low-mass stars (via BaSTi)
709	Base of the Red Giant (RG) Branch: Minimum in `log L` for high-mass or base of the RGB for low-mass stars (via BaSTi)
1079	RG bump 1: The maximum luminosity during the RGB Bump
1109	RG bump 2: The minimum luminosity during the RGB Bump
1509	RG tip: Tip of the RGB (TRGB) defined in 3 ways: If the last track model (line of file) has `YCEN > 0.1` the TRGB is either the minimum `log Teff` or the last model, which ever comes first. (low masses) If `YCEN = 0.0` at the last track model, TRGB is the minimum `log Teff` where `YCEN > 1-Z-0.1.` If there is still Hydrogen in the center (very low mass), TRGB is the final track model point.
1549	Beginning He Fusion: Start quiescent central He-burning phase Minimum of the luminosity due to He fusion after the TRGB, which dips as the star contracts, and then ramps up.
1699	YCEN=0.550
1799	YCEN=0.500
1859	YCEN=0.400
1959	YCEN=0.200
2039	YCEN=0.100
2119	YCEN=0.005
2199	YCEN=0.000
2279	AGB EEP 1: Helium (shell) fusion first overpowers hydrogen (shell) fusion
2359	AGB EEP 2: Hydrogen wins again (before TP-AGB).
2439	Starting of the central C-burning phase or beginning of TP-AGB.

For very high masses, the there is little meaning in some EEPs (e.g., TRGB and RG bumps) for now, those EEPs are linearly spaced in age.

Dictionary:
YCEN = Central abundance of Helium
XCEN = Central abundance of Hydrogen

Helium burning phases take place from 1549 on. There are four different track lengths:

539: Up to the MS turn off (low mass)
1509: Up to the TRGB (He-flash stars that will continue onto the horizontal branch)
2439: All phases (intermediate high mass)
890: Only Helium burning phases (Horizontal Branch tracks)

* Model number = line number + 1. Model number does not include header line of the file

File Format

Within each metallicity set (directory) there are a number of tracks (files). The file names are formatted by initial metallicity, helium, and mass (Z{}_Y{}_M{}.extension). Horizontal branch tracks are calculated separately and have extension .HB.dat all other tracks have only the .dat extension

Each file has six columns: log Age, Mass, log Teff, Mbol, log g, C/O in units yrs, Msun, K, bolometric mag, solar surface gravity (cgs), and unit less.

Notes on column formats:

Horizontal branch ages start at the zero age horizontal branch.
C/O is currently a place holder until I add the TP-AGB phases.
PARSEC does not print out log g or Mbol they are derived here from log Teff, log L and Mass:
Mbol = 4.77 - 2.5 * log L
log g = -10.616 + log mass + 4.0 * log Teff - log L

(all logs are base 10)

How to Cite

Use of PARSEC V1.2S tracks should at least reference Bressan et al. 2012. If you are using high mass tracks also reference Tang et al. 2014. If you are using low mass tracks also reference Chen et al. 2014.

If you use these tracks please also cite: