According to the documentation GFM_Metallicity can be converted to solar metallicity dividing by 0.0127, but which solar abundance tables are used internally?
For the radiative cooling which takes place during the simulation, you are correct that a set of relative abundances are assumed, since we do not do species-by-species cooling. (You can find the details in Vogelsberger+2013 Section 2.4).
On the other hand, the abundances which are tracked and stored (in GFM_Metals) do not assume any set of solar abundances, but instead are based on "yields" i.e. pre-existing stellar evolution calculations.
Justo Antonio Gonzalez Villalba
9 Jun '22
As you pointed out In Vogelsberger+2013 Section 2.4 I find: "We base our implementation of metal-line cooling therefore on the rates for a solar composition gas, and these rates are scaled linearly with the total metallicity Z.".
In this case, What is the assumed solar composition? (there seem to be several solar composition models in the literature, and I found no mention to a specific one in Vogelsberger+2013)
Dylan Nelson
9 Jun '22
Yes this isn't documented as well as it could be. These values, I believe, should be those from Asplund+2009. You would have to double-check with Mark Vogelsberger to make sure, as this was done a long time ago.
Jinning Liang
22 Jun '22
Hi Dylan,
Can I know which current stellar yields TNG use? I just see this question and I am curious.
Jinning Liang
22 Jun '22
@Dylan Nelson said:
What do you mean by, used internally?
For the radiative cooling which takes place during the simulation, you are correct that a set of relative abundances are assumed, since we do not do species-by-species cooling. (You can find the details in Vogelsberger+2013 Section 2.4).
On the other hand, the abundances which are tracked and stored (in GFM_Metals) do not assume any set of solar abundances, but instead are based on "yields" i.e. pre-existing stellar evolution calculations.
Hi Dylan,
Can I know which current stellar yields TNG use? I just see this question and I am curious.
Hi,
According to the documentation GFM_Metallicity can be converted to solar metallicity dividing by 0.0127, but which solar abundance tables are used internally?
For example in the xspec list there is angr, aspl, feld etc. Is any of these? https://heasarc.gsfc.nasa.gov/xanadu/xspec/manual/XSabund.html
Thanks in advance for your help!
What do you mean by, used internally?
For the radiative cooling which takes place during the simulation, you are correct that a set of relative abundances are assumed, since we do not do species-by-species cooling. (You can find the details in Vogelsberger+2013 Section 2.4).
On the other hand, the abundances which are tracked and stored (in GFM_Metals) do not assume any set of solar abundances, but instead are based on "yields" i.e. pre-existing stellar evolution calculations.
As you pointed out In Vogelsberger+2013 Section 2.4 I find: "We base our implementation of metal-line cooling therefore on the rates for a solar composition gas, and these rates are scaled linearly with the total metallicity Z.".
In this case, What is the assumed solar composition? (there seem to be several solar composition models in the literature, and I found no mention to a specific one in Vogelsberger+2013)
Yes this isn't documented as well as it could be. These values, I believe, should be those from Asplund+2009. You would have to double-check with Mark Vogelsberger to make sure, as this was done a long time ago.
Hi Dylan,
Can I know which current stellar yields TNG use? I just see this question and I am curious.
Hi Dylan,
Can I know which current stellar yields TNG use? I just see this question and I am curious.
Hi Jinning,
The yields of TNG are detailed in Pillepich+18.