Physics reach of the XENON1T dark matter experiment.

Abstract

The XENON1T experiment is currently in the commissioning phase at the Laboratori Nazionali del Gran Sasso, Italy. In this article we study the experiment's expected sensitivity to the spinindependent WIMP-nucleon interaction cross section, based on Monte Carlo predictions of the electronic and nuclear recoil backgrounds. The total electronic recoil background in 1 tonne fiducial volume and (1, 12) keV electronic recoil equivalent energy region, before applying any selection to discriminate between electronic and nuclear recoils, is (1.80 ± 0.15) • 10(−)(4) (kg•day•keV)(−)(1), mainly due to the decay of (222)Rn daughters inside the xenon target. The nuclear recoil background in the corresponding nuclear recoil equivalent energy region (4, 50) keV, is composed of (0.6 ± 0.1) (t•y)(−)(1) from radiogenic neutrons, (1.8 ± 0.3) • 10(−)(2) (t•y)(−)(1) from coherent scattering of neutrinos, and less than 0.01 (t•y)(−)(1) from muon-induced neutrons. The sensitivity of XENON1T is calculated with the Profile Likelihood Ratio method, after converting the deposited energy of electronic and nuclear recoils into the scintillation and ionization signals seen in the detector. We take into account the systematic uncertainties on the photon and electron emission model, and on the estimation of the backgrounds, treated as nuisance parameters. The main contribution comes from the relative scintillation efficiency Script L(eff), which affects both the signal from WIMPs and the nuclear recoil backgrounds. After a 2 y measurement in 1 t fiducial volume, the sensitivity reaches a minimum cross section of 1.6 • 10(−)(47) cm(2) at m() = 50 GeV/c(2).

Enhanced Higgs associated production with a top quark pair in the NMSSM with light singlets

“…Larger values of Ω th h 2 may be obtained by increasing µ which leads to reduced Higgsino component of the LSP, hence smaller annihilation cross-section. The LSP scattering cross-section on nucleons for all the benchmarks is below the LUX limits [68] but within the future reach of Xenon1T for direct detection via spin-independent (SI) LSP-nucleon interactions [69]. The compatibility with the LUX constraints is the reason for choosing negative value of M 1 in the benchmarks because µM 1 < 0 allows for some cancellations in the Higgs coupling to LSP which results in smaller SI scattering cross-section [70].…”

Blind spots for neutralino dark matter in the NMSSM

“…λ and κ. 4 This parameter vanishes for neutralinos which are pure (Higgsino or singlino) states. Its absolute value grows with…”

“…if the relic density would be smaller in a specific scenario, the experimental bounds should be appropriately rescaled (and hence relaxed). [4] and LZ [5] experiments. The colored areas at the bottom depict the neutrino background (NB) regions [6].…”

“…In consequence, significant portions of the neutralino sector parameter space has been excluded by LUX. The constraints will become soon even stronger with the forthcoming experiments such as XEXON1T [4] and LZ [5]. Nevertheless, there are points in the parameter space, so-called blind spots, for which the neutralino LSP spin-independent scattering cross-section (almost) vanishes at the tree level.…”

Analysis of the TeV-scale mirage mediation with heavy superparticles

“…The XENON1T experiment [92,93] and the PandaX-II experiment [94] give the most severe bounds on the spin-independent cross section. The current limit is about 10 −10 pb for m χ ∼ 100 GeV and 10 −9 pb for m χ ∼ 1100 GeV.…”