2.3 A Minimal Model of the Dark Sector
33
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eff
B B N N
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RGWD
LSND
miniBooNE
SLA C milli Q
LEP
LHC
WMAP
> 0.1
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h
DM
Ω
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oPS
Fig. 2.4 Existing limits for experiments on milli-charged dark-sector matter. Limits from stellar evolution (RGWD [32] and SN1987A [33]); N ef f during nucleosynthesis and in the cosmic
microwave background [32]; invisible decays of ortho-positronium (oPS) [34]; SLAC milliQ experiment [35]; reinterpretation of data from LSND and miniBooNE [36]; searches at LEP [37] and
LHC [38]; WMAP results and dark matter relic density abundance [38]
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LDMX @ CERN
Fermini @ FNAL
++
N A 6 4 (e )
++
)
μ
N A 6 4 (
milliQan:
-1
solid: 300 fb
-1
dashed: 3000 fb
Fig. 2.5 Future sensitivities for proposed experiments on milli-charged dark-sector matter. Future
sensitivities of NA64(e) ++ [39]; NA64(μ) [40]; FerMINI [41]; milliQAN [42]; LDMX [43]. The
sensitivity shown for LDMX @ CERN corresponds to 10 16 electrons-on-target and a beam energy
of 16 GeV. The existing limits are shown as gray areas. The plot is revised from [44]