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dc.contributor.authorKamaha, Alvine
dc.contributor.otherQueen's University (Kingston, Ont.). Theses (Queen's University (Kingston, Ont.))en
dc.date2015-03-13 16:25:08.295en
dc.date.accessioned2015-03-16T20:56:43Z
dc.date.available2015-03-16T20:56:43Z
dc.date.issued2015-03-16
dc.identifier.urihttp://hdl.handle.net/1974/12780
dc.descriptionThesis (Ph.D, Physics, Engineering Physics and Astronomy) -- Queen's University, 2015-03-13 16:25:08.295en
dc.description.abstractThe final results of the PICASSO experiment, with 409 kg days of exposure collected from November 2012 to January 2014, have yielded new limits for Spin-Dependent and Spin-Independent Dark Matter interactions.\\ The data collected and the various backgrounds were assiduously studied using Monte Carlo simulations and a new set of sophisticated analysis techniques including the wavelet analysis presented in this thesis. In general, a good suppression of most backgrounds was attained. The neutron background event rate was reduced to about a factor of 10 compared to the previous phase of the experiment. Electronic and acoustic noise events were thoroughly suppressed. A new class of ``mystery events'' were removed as well. All that remained was the irreducible alpha background.\\ No signal consistent with a WIMP Dark Matter hypothesis was observed. Consequently, an exclusion curve was obtained with a minimum limit at ${90\%}$ C.L. of ${\sigma_{\chi p}^{SD} =0.0228}$ pb at a WIMP mass of 20 GeV/$c^2$ in the Spin-Dependent sector. By combining results from 2012 and the current results, an improved constraint of ${\sigma_{\chi p}^{SD}}$(90${\%}$ C.L.) ${=0.0188}$ pb at 20 GeV/$c^2$ was placed on the Dark Matter interaction with protons in the Fluorine nuclei used in the detectors.\\ In addition, the new limits on WIMP-proton interactions in the Spin Independent sector exclude the DAMA/LIBRA results (at ${90\%}$ C.L.) for low masses below 12 GeV/$c^2$ and further constrain the published CRESST and CDMS Si discovery regions at low WIMP masses.en_US
dc.languageenen
dc.language.isoenen_US
dc.relation.ispartofseriesCanadian thesesen
dc.rightsThis publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner.en
dc.subjectDark Matter searchesen_US
dc.titleImproved Limits On The Existence Of Dark Matter. The Final Results From The PICASSO Experiment.en_US
dc.typeThesisen_US
dc.description.degreePh.Den
dc.contributor.supervisorNoble, Anthony J.en
dc.contributor.departmentPhysics, Engineering Physics and Astronomyen


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