The production of neutron-rich rare isotopes near $N=126$ seeks to elucidate the limit of existence for nuclear matter and explain the origin of heavy elements. In the most recent development, eight new isotopes, \nuc{182,183}{Tm}, \nuc{186,187}{Yb}, \nuc{189,190}{Lu}, and \nuc{191,192}{Hf}, were discovered in medium energy fragmentation and are presented here. This work marks the first time a \nuc{198}{Pt} primary beam was used to produce neutron-rich heavy isotopes near $N=126$. Two primary beam energies were explored, 85 MeV/u and 186 MeV/u. A total of 60 production cross sections were measured in the 85 MeV/u \nuc{198}{Pt} + \nuc{9}{Be} reaction, and 50 production cross sections were measured in the 85 MeV/u \nuc{198}{Pt} + Ni reaction. The \nuc{198}{Pt} + \nuc{9}{Be} cross sections were compared to \soft{EPAX3}, \soft{COFRA}, \soft{ABRABLA07}, and \soft{LISEAA}, showing the most consistent agreement with \soft{LISEAA}. The Ni target cross sections were systematically greater than the Be target cross sections by roughly an order of magnitude. This result suggests that heavy neutron-rich targets may aid in production of neutron-rich isotopes for medium energy fragmentation. Several pick-up reactions between \nuc{198}{Pt} and three separate targets (Be, Ni, C) were observed for the first time at intermediate energies. Nuclei up to two neutrons greater than the primary beam were observed. This work also led to the development of a novel charge state analysis for cross section calculations. The probability distribution for the charge state of the projectile residue immediately after reaction is generated from Monte Carlo calculations and optimization to experimental data. By using this new method, it was observed that not all primary beam electrons are stripped from the projectile residue during a fragmentation reaction. The number of electrons which remain on the projectile residue immediately after reaction (named \Ner) were observed to be inversely proportional to the number of protons removed in reaction.
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