The discovery of neutrino oscillations, and therefore that they have non-zero mass, provided the first conclusive proof of physics beyond the Standard Model [1]. Recently, neutrinos have become a valuable addition to the field of multi-messenger astrophysics to improve the study of distant astrophysical phenomena [2]. Fundamental to the operation of the numerous current neutrino experiments across a broad energy-scale is knowledge of the neutrino interaction rate or cross-section. In neutrino experiment, there exists a gap in the measurement of the neutrino-nucleon cross-section between approximately 300 GeV and a TeV. In this region, the Standard Model cross- section transitions away from its linear relationship with neutrino energy. This thesis describes a measurement of the total muon-neutrino-nucleon cross-section from 100 GeV to 5 TeV via a flux- dependent analysis performed on a dataset of through-going neutrino-induced muons detected by the IceCube Neutrino Observatory. An updated energy reconstruction utilizing DirectReco, a new method that generates event hypotheses using direct photon propagation, and tailored to the physics of the region of interest is applied. This provides several benefits, including improved accuracy of the event hypotheses and incorporation of the latest models of the glacial detector medium. The cross-section is measured as a normalization of the predicted flux where the parameters are scaling factors on the Standard Model cross-section, the Cooper-Sarkar-Mertsch-Sarkar (CSMS) model [3]. Two bins are defined, 100 - 350 GeV, overlapping with existing data, and 350 GeV - 5 TeV, the unmeasured region of phase space. A prior is calculated from existing accelerator neutrino beam cross-section measurements for the overlapping energy range of 100 - 350 GeV, additional input in constraining the fit for the low-energy region of the sample. The resultant Standard Model cross- section scaling factors are calculated both with the accelerator prior applied (case A) and without (case B). The results are, for 100 - 350 GeV and 350 GeV - 5 TeV regions, respectively, 0.82+0.08⁸́₂0.07 and 1.23+0.07-0.07 for case A and 0.27+0.07-0.05 and 0.78+0.08-0.07 for case B. This is the world's first measurement for the 350 GeV to 5 TeV energy region of the neutrino-nucleon cross-section, although forthcoming accelerator neutrino experiment FASER? will provide a comparable measurement of the cross-section of this energy range in the near future [4]. Both indicate tension with Standard Model, although interpretation of the result is subtly different for the two cases. Case A is a "best possible" measurement that utilizes the current maximal public knowledge of the cross-section. Case B is an IceCube-data-driven result, relatively free of influences inherent in existing cross-section models. The results presented here set a benchmark for future prospects of improvements and expansion of the IceCube-based cross-section studies -- to higher energies, and to multiple flavours -- and for the broad field.
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