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Colloquium: Annual modulation of dark matter

Freese, Katherine and Lisanti, Mariangela and Savage, Christopher (2013) Colloquium: Annual modulation of dark matter. Reviews of Modern Physics, 85 (4). pp. 1561-1581. ISSN 0034-6861. doi:10.1103/RevModPhys.85.1561.

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Direct detection experiments, which are designed to detect the scattering of dark matter off nuclei in detectors, are a critical component in the search for the Universe’s missing matter. This Colloquium begins with a review of the physics of direct detection of dark matter, discussing the roles of both the particle physics and astrophysics in the expected signals. The count rate in these experiments should experience an annual modulation due to the relative motion of the Earth around the Sun. This modulation, not present for most known background sources, is critical for solidifying the origin of a potential signal as dark matter. The focus is on the physics of annual modulation, discussing the practical formulas needed to interpret a modulating signal. The dependence of the modulation spectrum on the particle and astrophysics models for the dark matter is illustrated. For standard assumptions, the count rate has a cosine dependence with time, with a maximum in June and a minimum in December. Well-motivated generalizations of these models, however, can affect both the phase and amplitude of the modulation. Shown is how a measurement of an annually modulating signal could teach us about the presence of substructure in the galactic halo or about the interactions between dark and baryonic matter. Although primarily a theoretical review, the current experimental situation for annual modulation and future experimental directions is briefly discussed.

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Additional Information:© 2013 American Physical Society. Received 17 September 2012; published 1 November 2013. K. F. thanks M. Valluri and M. Zemp for useful conversations. K. F. acknowledges the support of the DOE and the Michigan Center for Theoretical Physics via the University of Michigan. K. F. thanks the Caltech Physics Department for hospitality and support during her sabbatical. K. F. is supported as a Simons Foundation Fellow in Theoretical Physics. M. L. is supported by the Simons Postdoctoral Fellows Program and the U.S. National Science Foundation, Grant No. NSF-PHY-0705682, and the LHC Theory Initiative. C. S. is grateful for financial support from the Swedish Research Council (VR) through the Oskar Klein Centre. C. S. thanks the Department of Physics & Astronomy at the University of Utah for support. K. F. and M. L. acknowledge the hospitality of the Aspen Center for Physics, which is supported by the National Science Foundation Grant No. PHY-1066293.
Funding AgencyGrant Number
Department of Energy (DOE)UNSPECIFIED
University of MichiganUNSPECIFIED
Caltech Physics DepartmentUNSPECIFIED
Simons FoundationUNSPECIFIED
Simons Postdoctoral Fellows ProgramUNSPECIFIED
LHC Theory InitiativeUNSPECIFIED
Swedish Research Council Oskar Klein CentreUNSPECIFIED
University of UtahUNSPECIFIED
Issue or Number:4
Classification Code:PACS: 95.35.+d, 12.60.-i, 95.30.Cq
Record Number:CaltechAUTHORS:20131203-112623433
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:42799
Deposited By: Tony Diaz
Deposited On:11 Dec 2013 00:04
Last Modified:10 Nov 2021 16:28

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