Little Higgs dark matter after PandaX-II/LUX-2016 and LHC Run-1

In the littlest higgs model with t-parity (lht), the t-odd heavy photon (a h ) is weakly interacting and can play the role of dark matter. we investigate the lower limit on the mass of a h dark matter under the constraints from higgs data, ewpos, r b , planck 2015 dark matter relic abundance, pandax-ii/lux 2016 direct detections and lhc-8 tev monojet results. we find that (1) higgs data, ewpos and r b can exclude the mass of a h up to 99 gev. to produce the correct dark matter relic abundance, a h has to co-annihilate with t-odd quarks (q h ) or leptons (ℓ h ); (2) the lux (pandax-ii) 2016 data can further exclude $$ {m}_{a_h} $$ < 380(270) gev for ℓ h -a h co-annihilation and $$ {m}_{a_h} $$ < 350(240) gev for q h − a h co-annihilation; (3) lhc-8 tev monojet result can give a strong lower limit, $$ {m}_{a_h} $$ > 540 gev, for q h -a h co-annihilation; (4) future xenon1t(2017) experiment can fully cover the parameter space of ℓ h -a h co-annihilation and will push the lower limit of $$ {m}_{a_h} $$ up to about 640 gev for q h -a h co-annihilation.