- #1
florian101
- 12
- 0
Hello
I try to get stable dark matter halos with n-body simulations. I set up the halo following a NFW-profile and I define the velocity distribution with a Gauss distribution or Edington inversion (the result is the same).
After approximately 2Gyr my cusp turns into a core...??
I use about 1 mil particles but the problem does not depend on the particles mass at all.
Obviously my particles in the center get a bit hot but I don't know what I am doing wrong... I am using a program to set up the halo which is well proofed and should give correct results.
All my simulations are done using Gadget2 which is also a well proofed n-body code...
The only possibility I could imagine is the softening length... I am using the third root of the mass as softening length for the particles and that is what is advised in the literature...?
Sometimes I use a higher values to absolutely avoid hard collisions...
I would be very thankful for any ideas what I could make wrong...
thank you very much
and best regards
florian
I try to get stable dark matter halos with n-body simulations. I set up the halo following a NFW-profile and I define the velocity distribution with a Gauss distribution or Edington inversion (the result is the same).
After approximately 2Gyr my cusp turns into a core...??
I use about 1 mil particles but the problem does not depend on the particles mass at all.
Obviously my particles in the center get a bit hot but I don't know what I am doing wrong... I am using a program to set up the halo which is well proofed and should give correct results.
All my simulations are done using Gadget2 which is also a well proofed n-body code...
The only possibility I could imagine is the softening length... I am using the third root of the mass as softening length for the particles and that is what is advised in the literature...?
Sometimes I use a higher values to absolutely avoid hard collisions...
I would be very thankful for any ideas what I could make wrong...
thank you very much
and best regards
florian