I have a question about spheres, because I am having a problem that I don't
really know how to solve. Basically, I have clusters of stars, and I want
to know how many stars are within 6 pc of each star. So, what I have done
is taken a sphere at each star position with a radius of 6 pc, and then
Now I wanted to double-check this number by brute-force, so I calculated
the distance between all the particles and then summed the masses of all
the particles that were less than 6 pc.
I am not getting the same values--they are close, but not the same (they
seem to mostly scatter up or down by a factor of 2).
So...to the question!! Because I am measuring particles in a grid code
(Enzo) is there any sort of shifting to the grid position instead of using
the particle positions here? Because stars are pretty packed I could
imagine that this could cause the differences I am seeing.
I am not sure that the problem is not something silly I am doing, but
wanted to check this possibility as well.
Dr. Stephanie Tonnesen
Associate Research Scientist
CCA, Flatiron Institute
New York, NY