Gas Particle Calculations Relative to Galaxy Centers
Jim O'Connor
21 Oct '22
Hi Dylan – I’m just starting a research project using the IllustrisTNG100 dataset and would appreciate your help and advice.
I would like to select a massive galaxy and calculate if there is gas inflow within 3kpc of the centre of the galaxy and I was wondering on how best to do this.
For example, do I need to translate the gas particle coordinates from the whole simulation to be relative to the centre of the selected galaxy?
Once I can calculate the gas particle inflow/outflow for one galaxy I would like to extend and apply the calculation to 30 or 40 other galaxies using Python.
The files are too big for my laptop but I have access to my university’s compute cluster and around 20Tb of storage – would that be enough?
Any help you can provide would be much appreciated.
Best Regards,
Jim.
Dylan Nelson
22 Oct '22
Hi Jim,
Yes you should first (i) select the halos of interest, then (ii) load their gas cell data, one halo at a time.
You should translate both the Coordinates and Velocities into the frame of the central galaxy / center of the halo. Then you can calculate a radial mass flux.
If you are just going to look at one redshift (e.g. one snapshot), then I would suggest to download it (~1 TB) onto your cluster.
Hi Dylan – I’m just starting a research project using the IllustrisTNG100 dataset and would appreciate your help and advice.
I would like to select a massive galaxy and calculate if there is gas inflow within 3kpc of the centre of the galaxy and I was wondering on how best to do this.
For example, do I need to translate the gas particle coordinates from the whole simulation to be relative to the centre of the selected galaxy?
Once I can calculate the gas particle inflow/outflow for one galaxy I would like to extend and apply the calculation to 30 or 40 other galaxies using Python.
The files are too big for my laptop but I have access to my university’s compute cluster and around 20Tb of storage – would that be enough?
Any help you can provide would be much appreciated.
Best Regards,
Jim.
Hi Jim,
Yes you should first (i) select the halos of interest, then (ii) load their gas cell data, one halo at a time.
You should translate both the Coordinates and Velocities into the frame of the central galaxy / center of the halo. Then you can calculate a radial mass flux.
If you are just going to look at one redshift (e.g. one snapshot), then I would suggest to download it (~1 TB) onto your cluster.
Otherwise the Lab service may be useful.
Many Thanks Dylan