getZahb: Import stellar track data for ZAHB

In stellaR: Evolutionary Tracks and Isochrones from Pisa Stellar Evolution Database

Import stellar track data for ZAHB

Description

Import a stellar ZAHB model.

Usage

 getZahb(z, y, ml, afe,
           baseURL="ftp://cdsarc.u-strasbg.fr/pub/cats/J/A+A/540/A26/")
     

Arguments

z	the initial metallicity of the model to get. Allowed values are 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008, 0.0009, 0.001, 0.002, 0.003, 0.004, 0.005, 0.006, 0.007, 0.008, 0.009, 0.01.
y	the initial helium abundance of the model to get. Allowed values are 0.25, 0.27, 0.33, 0.38, 0.42.
ml	the mixing-length of the model to get. Allowed values are 1.7, 1.8, 1.9.
afe	the alpha-enhanchment of the model to get. It can be one of afe = 0 for [alpha/Fe] = 0.0 or afe = 1 for [alpha/Fe] = 0.3.
baseURL	the URL of the base directory of the database from where get the models.

Details

As a sanity check, the function performs a consistency test on the parameters z, y, ml, afe by a call to testComposition.

By default the function requires an Internet access for data gathering. Tracks and isochrones are downloaded from the on-line repository CDS (http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/540/A26) It is also possible to gather data from a local download of the catalog, specifying as baseURL the root directory of the download. In this case the structure of the catalog and the names of files and directory must be preserved.

Value

getZahb returns an object of class zahb More specifically it is a list with elements:

z	the metallicity of the model
y	the initial helium content of the model
ml	the mixing-length value of the model
alpha.enh	the alpha-enhanchment of the model. It can be one of alpha.enh = 0 for [alpha/Fe] = 0.0 or alpha.enh = 1 for [alpha/Fe] = 0.3.
data	the dataset of stellar track, containing the following variables: mass mass of the star (in unit of solar mass) logTe logarithm of the effective temperature (Te in K) logL logarithm of the luminosity (L in unit of solar luminosity)

print, and plot methods are available for the two classes.

If baseURL points to an invalid path or CDS ftp site is unavailable the function returns NA and issues a warning.

References

M. Dell'Omodarme, G. Valle, S. Degl'Innocenti, and P.G. Prada Moroni (2012). The Pisa Stellar Evolution Data Base for low-mass stars. Astronomy and Astrophysics, 540, A26.

See Also

getTrk, getHbgrid, getIso, getTrkSet.

Examples

  ## Not run: 
  zahb <- getZahb(0.002, 0.25, 1.7, 0)

  ### get data from local directory /data
  zahb <- getZahb(0.002, 0.25, 1.7, 0, baseURL="/data/")
## End(Not run)

stellaR documentation built on April 11, 2022, 5:09 p.m.