Conversion mode photon analysis using the alpha magnetic spectrometer (AMS-02)

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2014
Postacı, Emirhan
The Alpha Magnetic Spectrometer (AMS-02) is a particle physics detector operating as an external module on the International Space Station (ISS). It is designed to search for antimatter and dark matter by measuring cosmic ray composition and flux. Dark matter does not interact electromagnetically, so cannot be detected directly with optical instruments. A strong candidate of dark matter is the lightest supersymmetric particle which can annihilate into the Standard Model particles, called the neutralino. If neutralinos annihilate in the galactic halo, they could result in an excess of particles that can be detected by the AMS-02. Any peaks in the positron, antiproton, or photon spectrum could signal the presence of neutralinos, but would need to be distinguished from other complex astrophysical signals. Photon analysis can be done in two ways: calorimetric mode and conversion mode. In the calorimetric mode of photon analysis, photons leave no trace in subdetectors down to the ECAL. In the conversion mode, photons which are converted to electron-positron pairs in the upper parts of the AMS-02 are studied. This thesis outlines the study of conversion mode photon analysis above 100 GeV energy.

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Citation Formats
E. Postacı, “Conversion mode photon analysis using the alpha magnetic spectrometer (AMS-02),” M.S. - Master of Science, Middle East Technical University, 2014.