Evolution Model Object¶
Stellar evolution models are defined as classes in
spisea/evolution.py. These can be called by:
from spisea import evolution
evo = evolution.<model_name>()
The evolution object is an input for the Isochrone Object.
Below is a table of the evolution model grids currently supported by SPISEA.
Model Name |
Mass Range |
log(Age) Range |
Metallicity Values |
Ref |
|---|---|---|---|---|
M⊙ |
Years |
[Fe/H] |
||
|
0.10 – 300 |
5.01 – 10.30 |
-4.0, -3.5, -3.0, -2.5, -2.0, -1.75, -1.5, -1.25, -1.0, -0.75, -0.5, -0.25, 0, 0.25, 0.5 |
v1.2; Choi et al. (2016) |
|
0.08 – 120 |
6.00 – 10.09 |
0 |
Appendix B; Hosek et al. (2020) |
|
0.01 – 120 |
6.00 – 10.00 |
0 |
Appendix; Begbie et al. (2026) |
|
0.10 – 65 |
6.60 – 10.12 |
0 |
Bressan et al. (2012) |
|
0.07 – 1.4 |
5.70 – 10.0 |
0 |
Baraffe et al. (2015) |
|
0.80 – 300 |
6.00 – 8.0 |
0 |
Ekström et al. (2012) |
|
0.20 – 7 |
6.00 – 8.0 |
0 |
Tognelli et al. (2011) |
|
0.0005–0.075 |
6.00 - 10.00 |
0 |
Phillips et al. (2020) |
|
0.0005–0.083a |
6.00 - 10.00 |
-0.5, 0, 0.5 |
Marley et al. (2021) |
Footnotes
a Actual maximum value given by the Sonora models (Marley et al., 2021) relies on the age of the cluster. For example, for log(Age)=6.0, the mass range is limited to 0.0005 - 0.011 M⊙.
Please note the stellar mass range, age range, and metallicity values of the evolution model grid you choose:
Stars generated from the IMF Object (controlled by the massLimits variable) that fall outside of the mass range of the evolution model will be dropped from the final cluster table, unless the IFMR is defined (which will catch all the high mass stars and get their compact object values)
SPISEA will throw an error if you request an age outside of the evolution model age range
SPISEA will use the evolution model with the closest available metallicity to the requested value
If you require other evolution models or need to expand the existing grids, please see Adding Evolution Models.
ModelMismatch Error¶
Since SPISEA v2.1.4, we began tracking the version of the evolution
model grid (e.g., the evolution models stored in
<SPISEA_MODELS>/evolution).
Each evolution model class has a required model grid
version assigned to it. If your evolution model grid
does not match or exceed the minimum version required by
your desired evolution model, a ModelMismatch
exception will be raised.
To resolve the ModelMismatch error, please
re-download the latest version of the evolution
model grid in the installation instructions (Stellar Evolution and Atmosphere Models).