Fix a small typo and update mass bound in python
Fixed a small typo in PsiPlusPsiCascade.cxx and updated the X particle mass upper limit in BPHY23.py. Affect BPhys derivations only.
Fixed a small typo in PsiPlusPsiCascade.cxx and updated the X particle mass upper limit in BPHY23.py. Affect BPhys derivations only.