Heavy ion collisions are used for probing the momentum dependence of the nuclear symmetry energy. This momentum dependence causes an apparent reduction in the inertial mass of nucleons lying within the mean field potential. Because the actual masses remain unchanged, apparent mass is termed an effective mass that describes the acceleration under the influence of a momentum independent potential. Along with a reduction in effective mass there is also a splitting between the effective masses of protons and neutrons. Currently theoretical models do not agree as to which particle, protons or neutrons has the larger effective mass and, in particular, how these effective masses decrease with density. Observables that can be used for probing this effective mass splitting include both n/p single and double ratios of neutron energy spectra divided by proton energy spectra. The end result of this dissertation is not to obtain a final answer to these questions regarding the effective mass splitting. However, it lays the ground work for creating accurate ratios of neutron energy spectra over proton energy spectra needed for this purposes. In doing so, it demonstrates how to create charged particle energy spectra and corrected them for background coming from punch-through events and for reaction losses within the CsI(Tl) crystals. After producing background corrected energy spectra it studies isoscaling phenomenon in several of the studied reaction systems. Using that knowledge, it goes on to demonstrate how to obtain coalescence invariant neutron/proton spectral ratios.To probe the effective mass splitting we ran an experiment at the NSCL that measured collisions between calcium beams on nickel and tin targets. For this experiment a new set of charged particle energy loss telescopes were constructed called the High Resolution Array 10 (HiRA10). Each of the 12 telescopes in this array are constructed using a 1.5 mm thick silicon detector backed by a pack of four 10 cm long CsI(Tl) crystals that are used to measure the energy and identifying the species of the particle. These new crystals are longer than the 4 cm long CsI crystals in its predecessor HiRA device. This increased length of the crystals allows the new HiRA10 to detect higher energy particles (Protons up to 0303200 MeV, Deuterons up to 0303264 and Tritons up to 0303312). While the increased length of the crystals increased the range of energies that can be detected it also increased the backgrounds present within the HiRA10 charged particle energy spectra. Therefore one of the goals of this work was to apply corrections for background within the HiRA10 CsI crystals.After correcting these spectra, the other goal of this work is to create isoscaling ratios for two of the measured systems. Isoscaling ratios are created by dividing the energy spectra of a particle species coming from two reaction systems. Isoscaling ratios provide several observations which can be compared to theoretical models. The first of these is the grouping of isoscaling ratios for different particle species based on that particles proton and neutron numbers. Second, assuming the reaction system is at local thermal and chemical equilibrium we use these isoscaling ratios to determine the difference between proton and neutron chemical potentials in these two systems.The final goal of this work will be to extract preliminary N/P double ratios using pseudo neutron spectra created by combining charged particle spectra. These pseudo neutron spectra are extracted with two different methods, one based on a thermodynamic method and the other based on charged particle coalescence. The extracted double ratio is then compared to simulations using two Skyrme interaction potentials, one with the effective mass of the proton greater than that of the neutron and the other where the neutron effective mass is greater.
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