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dc.contributor.advisorSushkov, Alexanderen_US
dc.contributor.authorAybas, Denizen_US
dc.date.accessioned2021-10-06T18:00:40Z
dc.date.issued2021
dc.identifier.urihttps://hdl.handle.net/2144/43118
dc.description.abstractAstrophysical observations indicate the existence of dark matter through its gravitational interaction, but since its other interactions remain undetected, its particle nature is still unknown. There are several dark matter candidates, one being a hypothetical particle called axion that can have three types of non-gravitational couplings: electromagnetic, electric dipole moment (EDM), and gradient. This dissertation presents experimental approaches and axionlike dark matter search results from two table-top experiments: Cosmic Axion Spin Precession Experiment (CASPEr-electric) sensitive to EDM and gradient couplings, and Search for Halo Axions with Ferromagnetic Toroids (SHAFT) sensitive to electromagnetic coupling. CASPEr-electric is a resonant search for axionlike dark matter through the induced nuclear spin precession. The experimental approach is measuring nuclear magnetic resonance (NMR) of the heavy atom in a ferroelectric crystal. Experimental setup is characterized using pulsed NMR calibration measurements. Recorded search data that is sensitive to axionlike dark matter is analyzed by optimal filtering and then setting a detection threshold based on the histogram of power spectral density modeled as a Gaussian distribution. The candidates above the threshold are all rejected through statistical fluctuations and scan/re-scan measurements. CASPEr-electric places the upper bounds on the EDM and gradient couplings of axionlike dark matter in the Compton frequency range from 39.1 MHz to 40.2 MHz. SHAFT is a broadband search for axionlike dark matter through the induced oscillatory magnetic field. The resultant magnetic flux is measured with a precision magnetometer called superconducting quantum interference device (SQUID), coupled to a coil placed on the inner surface of a ferromagnetic toroid. After analyzing the search data, all candidates are rejected and SHAFT places a limit on electromagnetic coupling of axionlike dark matter between 3 kHz and 3 MHz Compton frequencies. Finally, coupling limits placed by CASPEr-electric and SHAFT are evaluated in the wider parameter space, and possible future directions that both experiments could take to improve their sensitivities to axionlike dark matter are discussed.en_US
dc.language.isoen_US
dc.subjectElectrical engineeringen_US
dc.subjectAxionen_US
dc.subjectCASPEren_US
dc.subjectDark matteren_US
dc.subjectNuclear magnetic resonanceen_US
dc.subjectPrecision magnetometryen_US
dc.titleSearching for axionlike dark matter using nuclear magnetic resonance and precision magnetometryen_US
dc.typeThesis/Dissertationen_US
dc.date.updated2021-09-27T19:04:21Z
dc.description.embargo2022-09-27T00:00:00Z
etd.degree.nameDoctor of Philosophyen_US
etd.degree.leveldoctoralen_US
etd.degree.disciplineElectrical & Computer Engineeringen_US
etd.degree.grantorBoston Universityen_US
dc.identifier.orcid0000-0002-0392-5979


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