Import a stellar isochrone.
getIso(age, z, y, ml, afe,
baseURL="ftp://cdsarc.u-strasbg.fr/pub/cats/J/A+A/540/A26/")
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.
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.
the initial helium abundance of the model to get. Allowed values are 0.25, 0.27, 0.33, 0.38, 0.42.
the mixing-length of the model to get. Allowed values are 1.7, 1.8, 1.9.
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.
the URL of the base directory of the database from where get the models.
getIso
returns an object of class iso
.
More specifically this is a list with elements:
the age of the isochrone (in Gyr)
the metallicity of the model
the initial helium content of the model
the mixing-length value of the model
the dataset of stellar isocrone, containing the following five variables:
logarithm of the luminosity (L in unit of solar luminosity)
logarithm of the effective temperature (Te in K)
mass of the star (in unit of solar mass)
radius of the star (in unit of solar radius)
logarithm of the surface gravity (g in cm s^-2)
If baseURL points to an invalid path or CDS ftp site is unavailable the function returns NA and issues a warning.
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.
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.
# NOT RUN {
# }
# 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/")
# }
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