Matching DMO particles between the TNG and DMO simulations.
ZHAO AN
9 Jan
Hello!
Are the dark matter particles with the same particle IDs consistent in the DMO and TNG simulations? I am trying to find the corresponding halos in the DMO and TNG simulations, and one method is: we can extract the unique identifiers of the 100 most gravitationally bound particles within every halo of a given DMO run, and then find the halo hosting those same particles in the corresponding hydrodynamic run. If the particle IDs cannot be matched, then this method won't work.
Thank you very much for your explanation! However, I encountered a problem when using this method: I selected halo whose id is 0(the biggest halo in group) from TNG300-1 and its corresponding DMO simulation (their centroids are very close, so they are almost certainly the corresponding halos), and then selected the 100 particles with the smallest 'Potential' (i.e., the largest gravitational potential) from each, and compared their indices. I found that only 3 particles corresponded. If I increased the particle number to 1000, 218 particles corresponded. Is this result reasonable? I originally expected that the 100 particles with the largest gravitational potential would correspond exactly.
Dylan Nelson
20 Jan
I don't have a sense, but I think this might be reasonable - due to stochasticity effects, it is likely quite easy to shuffle the binding energy order significantly. What fraction of the entire halo match? I would suggest to just run your method on your halos of interest, and then cross-check with the catalog linked above, to see the level of agreement.
ZHAO AN
21 Jan
For the snapshot with snapnum 50, the largest halo has a total match of 9.4% with the corresponding halo in the DMO simulation. Next, I will cross-check based on the results linked above. Thank you！
ZHAO AN
22 Jan
I couldn’t find the file subhalo_matching_to_dark.hdf5 in the JupyterLab Workspace. Which folder is it in?
Dylan Nelson
22 Jan
Many supplementary catalogs are not directly available in the Lab, but you can download it into the Lab if you need to.
Hello!
Are the dark matter particles with the same particle IDs consistent in the DMO and TNG simulations? I am trying to find the corresponding halos in the DMO and TNG simulations, and one method is: we can extract the unique identifiers of the 100 most gravitationally bound particles within every halo of a given DMO run, and then find the halo hosting those same particles in the corresponding hydrodynamic run. If the particle IDs cannot be matched, then this method won't work.
Thank you very much.
Yes that is correct.
A similar method has been used to create the Subhalo Matching Between Runs catalogs, which you might find useful.
Thank you very much for your explanation! However, I encountered a problem when using this method: I selected halo whose id is 0(the biggest halo in group) from TNG300-1 and its corresponding DMO simulation (their centroids are very close, so they are almost certainly the corresponding halos), and then selected the 100 particles with the smallest 'Potential' (i.e., the largest gravitational potential) from each, and compared their indices. I found that only 3 particles corresponded. If I increased the particle number to 1000, 218 particles corresponded. Is this result reasonable? I originally expected that the 100 particles with the largest gravitational potential would correspond exactly.
I don't have a sense, but I think this might be reasonable - due to stochasticity effects, it is likely quite easy to shuffle the binding energy order significantly. What fraction of the entire halo match? I would suggest to just run your method on your halos of interest, and then cross-check with the catalog linked above, to see the level of agreement.
For the snapshot with snapnum 50, the largest halo has a total match of 9.4% with the corresponding halo in the DMO simulation. Next, I will cross-check based on the results linked above. Thank you！
I couldn’t find the file subhalo_matching_to_dark.hdf5 in the JupyterLab Workspace. Which folder is it in?
Many supplementary catalogs are not directly available in the Lab, but you can download it into the Lab if you need to.
Okay, thank you for your explanation.