TY - JOUR
T1 - Modulation effects in dark matter-electron scattering experiments
AU - Lee, Samuel K.
AU - Lisanti, Mariangela
AU - Mishra-Sharma, Siddharth
AU - Safdi, Benjamin R.
N1 - Publisher Copyright:
© 2015 American Physical Society.
PY - 2015/10/16
Y1 - 2015/10/16
N2 - One of the next frontiers in dark-matter direct-detection experiments is to explore the MeV to GeV mass regime. Such light dark matter does not carry enough kinetic energy to produce an observable nuclear recoil, but it can scatter off electrons, leading to a measurable signal. We introduce a semianalytic approach to characterize the resulting electron-scattering events in atomic and semiconductor targets, improving on previous analytic proposals that underestimate the signal at high recoil energies. We then use this procedure to study the time-dependent properties of the electron-scattering signal, including the modulation fraction, higher-harmonic modes and modulation phase. The time dependence can be distinct in a nontrivial way from the nuclear scattering case. Additionally, we show that dark-matter interactions inside the Earth can significantly distort the laboratory-frame phase-space distribution of sub-GeV dark matter.
AB - One of the next frontiers in dark-matter direct-detection experiments is to explore the MeV to GeV mass regime. Such light dark matter does not carry enough kinetic energy to produce an observable nuclear recoil, but it can scatter off electrons, leading to a measurable signal. We introduce a semianalytic approach to characterize the resulting electron-scattering events in atomic and semiconductor targets, improving on previous analytic proposals that underestimate the signal at high recoil energies. We then use this procedure to study the time-dependent properties of the electron-scattering signal, including the modulation fraction, higher-harmonic modes and modulation phase. The time dependence can be distinct in a nontrivial way from the nuclear scattering case. Additionally, we show that dark-matter interactions inside the Earth can significantly distort the laboratory-frame phase-space distribution of sub-GeV dark matter.
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U2 - 10.1103/PhysRevD.92.083517
DO - 10.1103/PhysRevD.92.083517
M3 - Article
AN - SCOPUS:84945956626
SN - 1550-7998
VL - 92
JO - Physical Review D - Particles, Fields, Gravitation and Cosmology
JF - Physical Review D - Particles, Fields, Gravitation and Cosmology
IS - 8
M1 - 083517
ER -