Can't get the same number density as previous literature by using mdpd method on LAMMPS

Dear lammps user,
I am doing mdpd on liquid drops and have faced a problem.
In this reserch done by Sandia National Laboratories in 2011 (, the density of the mdpd drop (A=-40 B=40 gamma=0.5 rd=0.75 rc=1.0) is calculated and equals 5.12.
However, after I used the hybrid mdpd/rhosum mdpd pairstyle simulated the same system, I only found that the density equalled 5.6. I have also tried other system, and the density are always larger than that of previous research.
I am wondering whether it is the algorithm of LAMMPS caused the differences…
Could anyone please help me with this problem? I would really appreciate it!

Your best chances to get help with this kind of problem is to contact the author of the corresponding package in LAMMPS, since this is less of a LAMMPS problem, but more an issue of the “science”.
Since the author contributing this package to LAMMPS is a co-author of the publication describing the method, you should in a first order approximation assume that the algorithm is correctly implemented into LAMMPS. Thus the probability is rather high that you are not correctly using it. Information about the contributing author is here: 6.2. Package details — LAMMPS documentation
and in the source code.

OK Thanks for your advice!