A Method to Account for Hydroxide Contamination in Characterizing the Giant Monopole Resonance to Determine an Accurate K$_{\mathrm{\tau \thinspace }}$

Measurements on the isoscalar giant monopole resonance (ISGMR) in finite nuclei over a range of isotopes permit the extraction of K$_{\mathrm{\tau }}$, the nuclear incompressibility asymmetry term. K$_{\mathrm{\tau \thinspace }}$is critical to understanding proton/neutron asymmetric systems. A recent study has claimed that the energy of the ISGMR is higher in heavier calcium isotopes than lighter ones, indicating a positive K$_{\mathrm{\tau }}$. This is surprising when compared to most research on extracting finite nuclear incompressibilities from giant resonances. To independently verify the claim, a simultaneous study of the GMR of $^{\mathrm{40,42,44,48}}$Ca was conducted. However, contributions from hydroxide contamination were found in the $^{\mathrm{48}}$Ca foil used in the experiment. The methodology for accounting for the contribution of $^{\mathrm{16}}$O to the experimental spectra will be presented, and the implications will be discussed.