I have a few plotting questions:

1. http://yt-project.org/docs/3.2/cookbook/simple_plots.html#simple-particle-plot

p.set_unit('particle_mass', 'Msun')

In the above plot, Colorbar range is approximately Mass=10^5-10^9. When making a plot using ParticlePlot or ParticleProjectionPlot, can I manually force the range on the colorbar?

2. The label on the colorbar says "Particle Mass". Instead, shouldn't it be saying something like mass_per_pixel, since the plot is showing the total number of particles projected along the z-axis? How can we rename the colorbar?

3. Can contours of mass be added to the above plot, using annotate?