Following up from the previous post:

https://drupal.star.bnl.gov/STAR/blog/dmawxc/update-04262018-run-9-pp-resolution-width-different-calculation

Nihar suggested that the cut on pTreco might be biasing the calculation of the resolution widths, so I redid the calculation without imposing such a cut (though all of the other QA cuts on nFit, dca, etc. are applied). 

And for clarity, I redid the calculation using bin widths of 0.2 and 0.3 GeV/c respectively.