getIso: Import stellar isochrones data
In stellaR: Evolutionary Tracks and Isochrones from Pisa Stellar Evolution Database

getIso

R Documentation

Import stellar isochrones data

Description

Import a stellar isochrone.

Usage

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

Arguments

`age`	the age (in Gyr) of the isochrone to get. Allowed values are 8.0, 8.5, 9.0, 9.5, 10.0, 10.5, 11.0, 11.5, 12.0, 12.5, 13.0, 13.5, 14.0, 14.5, 15.0.
`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

getIso returns an object of class iso. More specifically this is a list with elements:

`age`	the age of the isochrone (in Gyr)
`z`	the metallicity of the model
`y`	the initial helium content of the model
`alpha.enh`	the mixing-length value of the model
`data`	the dataset of stellar isocrone, containing the following five variables: logL logarithm of the luminosity (L in unit of solar luminosity) logTe logarithm of the effective temperature (Te in K) mass mass of the star (in unit of solar mass) radius radius of the star (in unit of solar radius) logg logarithm of the surface gravity (g in cm s^-2)

print, and plot methods are available for the class.

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.

Examples

  ## Not run: 
  iso <- getIso(12.0, 0.002, 0.25, 1.7, 0)

  ### get data from local directory /data
  iso <- getIso(12.0, 0.002, 0.25, 1.7, 0, baseURL="/data/")
## End(Not run)

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