dc.contributor.advisor Gabrielse, Gerald dc.contributor.advisor Greiner, Markus dc.contributor.advisor Reece, Matthew dc.contributor.author Panda, Cristian Daniel dc.date.accessioned 2019-08-08T09:21:37Z dc.date.created 2019-03 dc.date.issued 2019-01-07 dc.date.submitted 2019 dc.identifier.citation Panda, Cristian Daniel. 2019. Order of Magnitude Improved Limit on the Electric Dipole Moment of the Electron. Doctoral dissertation, Harvard University, Graduate School of Arts & Sciences. dc.identifier.uri http://nrs.harvard.edu/urn-3:HUL.InstRepos:41121303 * dc.description.abstract The Standard Model of particle physics accurately describes with amazing precision all particle physics measurements made in the laboratory. However, it is unable to answer many central questions that arise from cosmological observations, such as the nature of dark matter and why matter dominates over antimatter throughout the Universe. Theories containing particles and interactions beyond the standard model, such as models incorporating supersymmetry, may explain these phenomena. Such particles can come into virtual existence in the vacuum and then interact with real particles to modify their properties. For example, the existence of very massive particles whose interactions violate time-reversal symmetry, as needed to explain the cosmological matter–antimatter asymmetry, gives rise to an electric dipole moment along the spin axis of the electron. To date no electric dipole moments (EDM), of the electron or other fundamental particles, have been observed. However, dipole moments only slightly smaller than current bounds can arise from new particles more massive than any known to exist. Here we present a new measurement of the electron's electric dipole moment (eEDM), $d_e$=\result, obtained by measuring the spin precession of electrons subjected to the huge intramolecular electric field accessible in the thorium monoxide molecule. The sensitivity of our measurement is one order of magnitude better than any previous work and probes for the existence of new particles with mass far beyond the direct reach of the Large Hadron Collider. Since our measurement is consistent with zero, we report an upper limit of $|d_e|$<\upperlimitFeldman, which sets very strong constraints on a wide range of theories that predict new physics at energy scales directly accessible to colliders. dc.description.sponsorship Physics dc.format.mimetype application/pdf dc.language.iso en dash.license LAA dc.subject electron dc.subject EDM dc.subject electric dipole moment dc.subject dipole dc.subject beyond the Standard Model dc.subject BSM dc.subject CP dc.subject symmetry dc.subject fundamental dc.subject super-symmetry dc.subject molecule dc.subject beam dc.subject ThO dc.subject thorium monoxide dc.subject spin precession dc.subject STIRAP dc.subject matter-antimmater asymmetry dc.subject BAU dc.subject dark matter dc.subject spin dc.title Order of Magnitude Improved Limit on the Electric Dipole Moment of the Electron dc.type Thesis or Dissertation dash.depositing.author Panda, Cristian Daniel dc.date.available 2019-08-08T09:21:37Z thesis.degree.date 2019 thesis.degree.grantor Graduate School of Arts & Sciences thesis.degree.grantor Graduate School of Arts & Sciences thesis.degree.level Doctoral thesis.degree.level Doctoral thesis.degree.name Doctor of Philosophy thesis.degree.name Doctor of Philosophy dc.type.material text thesis.degree.department Physics thesis.degree.department Physics dash.identifier.vireo dc.identifier.orcid 0000-0002-2284-9756 dash.author.email cristian.panda@gmail.com
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