Hi,
I've been working with TNG300-1 for some time now and have noticed something weird about snapshot 40. I have made some of my own catalogues using the stellar particle data, omitting wind particles in my calculations of stellar mass, centre of mass, galactic velocity and shapes.
For all other snapshots that I have used my scripts on, I am left with around 2-3 million galaxies once omitting those that are only wind particles. (I have used snapshots 99,91,84,78,59,50,39) For snap 40 I have ~588 thousand.
Furthermore, a comparison of catalogue mass vs my summation of particle masses that omit wind particles yields very similar results for all snapshots except 40. M_nowind/M is always 1 to within 1e-6 or so and for snapshot 40 it ranges between 0.88 and 1.37.
When taking the intersection of a subsample of the galaxies in my catalogue and the Stellar Circularities, Angular Momenta, Axis Ratios catalogue, I am usually left with around 70-100 thousand galaxies, whereas snapshot 40 leaves me with 1225.
As the stats for snapshot 39 are the same as the other snapshots, I have to assume this is not some redshift evolution effect, but something internal to snapshot 40.
I was wondering if you were aware of these differences and if some bug (likely to do with the wind particles) has created these effects?
Is there anything I need to account for in my research?
Hi,
I've been working with TNG300-1 for some time now and have noticed something weird about snapshot 40. I have made some of my own catalogues using the stellar particle data, omitting wind particles in my calculations of stellar mass, centre of mass, galactic velocity and shapes.
For all other snapshots that I have used my scripts on, I am left with around 2-3 million galaxies once omitting those that are only wind particles. (I have used snapshots 99,91,84,78,59,50,39) For snap 40 I have ~588 thousand.
Furthermore, a comparison of catalogue mass vs my summation of particle masses that omit wind particles yields very similar results for all snapshots except 40. M_nowind/M is always 1 to within 1e-6 or so and for snapshot 40 it ranges between 0.88 and 1.37.
When taking the intersection of a subsample of the galaxies in my catalogue and the Stellar Circularities, Angular Momenta, Axis Ratios catalogue, I am usually left with around 70-100 thousand galaxies, whereas snapshot 40 leaves me with 1225.
As the stats for snapshot 39 are the same as the other snapshots, I have to assume this is not some redshift evolution effect, but something internal to snapshot 40.
I was wondering if you were aware of these differences and if some bug (likely to do with the wind particles) has created these effects?
Is there anything I need to account for in my research?