vice.solar_z

The VICE dataframe: solar composition

Stores the abundance by mass of all recognized elements in the sun. Stored values are of type float; defaults are assigned according to the Asplund et al. (2009) [1] photospheric measurements. For elements where the photospheric measurements were not feasible, this object adopts the meteoritic measurements.

New in version 1.2.0: In versions >= 1.2.0, users may modify the values stored for each individual element. The only restriction imposed is that the values be between 0 and 1. In prior versions, the values stored by this dataframe were not modifiable.

Indexing

  • str [case-insensitive]

    The symbol of a chemical element as it appears on the periodic table.

Item Assignment

  • float

    The new abundance by mass (i.e. the mass fraction) of a given element within the sun. Must be between 0 and 1.

Notes

Changes to the values stored by this object will be reflected in any chemical evolution simulations ran by VICE. However, these values will reset every time the python interpreter is restarted.

Default values are calculated with vice.solar_z.epsilon_to_z_conversion. For details, see the associated documentation.

For helium (‘he’), the default value is modified from the photospheric abundance of He as measured by Asplund et al. (2009) (Y = 0.2485) to their recommended bulk abundance (Y = 0.2703) (see their section 3.12).

Functions

  • keys

  • todict

Example Code

>>> import vice
>>> vice.solar_z['o']
0.00572
>>> vice.solar_z['o'] = 0.005
>>> vice.solar_z['o']
0.005
>>> vice.solar_z['c']
0.00236
>>> vice.solar_z['c'] *= 1.1 # increase by 10 percent
0.0025960000000000002