Annual modulation in direct dark matter searches

Abstract

The measurement of an annual modulation in the event rate of direct dark matter detection experiments is a powerful tool for dark matter discovery. Indeed, several experiments have already claimed such a discovery in the past decade. While most of them have later revoked their conclusions, and others have found potentially contradictory results, one still stands today. This paper explains the potential as well as the challenges of annual modulation measurements, and gives an overview on past, present and future direct detection experiments.

Dark matter substructure under the electron scattering lamppost

“…A particularly interesting feature of direct detection searches that DM substructure can affect is the seasonal variation of a DM signal [36]. The presence of DM substructure could produce an annual modulation signatures differing in both amplitude and phase from what is expected for DM in the SHM [37,38].…”

Event Rates for the Scattering of Weakly Interacting Massive Particles from 23Na and 40Ar

“…There are many experimental efforts [10][11][12][13] to detect WIMPs via their scattering from the nuclei of the detector providing finger-prints regarding their existence. Some of these are the Super CDMS SNOLAB project, XENON1T, PICO-60, EDELWEISS and so on; see, for example, [13][14][15][16].…”

“…There are many experimental efforts [10][11][12][13] to detect WIMPs via their scattering from the nuclei of the detector providing finger-prints regarding their existence. Some of these are the Super CDMS SNOLAB project, XENON1T, PICO-60, EDELWEISS and so on; see, for example, [13][14][15][16]. Nuclear isotopes like 23 Na, 40 Ar, 71 Ga, 73 Ge, 75 As, 127 I, 133 Cs and 133 Xe, are among the popular detector nuclei; see [12,13,17] and references therein.…”

“…Some of these are the Super CDMS SNOLAB project, XENON1T, PICO-60, EDELWEISS and so on; see, for example, [13][14][15][16]. Nuclear isotopes like 23 Na, 40 Ar, 71 Ga, 73 Ge, 75 As, 127 I, 133 Cs and 133 Xe, are among the popular detector nuclei; see [12,13,17] and references therein. Our focus in this paper is on 23 Na (the only stable isotope in the natural Na) and 40 Ar (with 99.59% abundance in the natural Ar).…”

“…In these experiments, the predicted annual modulation was not yet confirmed [13], though a signal of annual modulation in NaI was reported in [19]. However, the SABRE experiment [20] aims to directly measure the annual modulation of the dark matter interaction rate with NaI(Tl) crystals.…”