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arXiv · 1105.5644

Direct detection and CMB constraints on light DM scenario of top quark asymmetry and dijet excess at Tevatron

Andi Hektor·Gert Hütsi·Mario Kadastik·Kristjan Kannike·Martti Raidal·David M. Straub
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Abstract

We study in detail the model by Isidori and Kamenik that is claimed to explain the top quark forward-backward asymmetry at Tevatron, provide GeV-scale dark matter (DM), and possibly improve the agreement between data and theory in Tevatron W+jj events. We compute the DM thermal relic density, the spin-independent DM-nucleon scattering cross section, and the cosmic microwave background constraints on both Dirac and Majorana neutralino DM in the parameter space that explains the top asymmetry. A stable light neutralino is not allowed unless the local DM density is 3-4 times smaller than expected, in which case Dirac DM with mass around 3 GeV may be possible, to be tested by the Planck mission. The model predicts a too broad excess in the dijet distribution and a strong modification of the missing E_T distribution in W+jj events.

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Andi Hektor, Gert Hütsi, Mario Kadastik, Kristjan Kannike, Martti Raidal, David M. Straub. 2011-08-17. Direct detection and CMB constraints on light DM scenario of top quark asymmetry and dijet excess at Tevatron. https://doi.org/10.1103/physrevd.84.031701

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