Recently Tevatron released their measurements on invariant mass spectrum of electron/positron, as well as the di-jet arising from WW+WZ production with one W leptonically decay. Though the statistics is not significant, there are two bumps around 240 GeV and 120-160 GeV respectively. We proposed that the two bumps correspond to the extra light gauge bosons Z ′ and W ′ , which couple with quarks with the deci-weak strength.In this brief report, we also simulated di-jet invariant mass distribution at the current running LHC.

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Both D0 and CDF at Tevatron reported the measurements of forward-backward asymmetry in top pair production, which showed possible deviation from the standard model QCD prediction. In this paper, we explore how to examine the same higher-order QCD effects at the more powerful Large Hadron Collider.PACS numbers: 14.65. Ha, 12.38.Bx The top quark is the heaviest ever known fermion and is thought to be related to the mechanism of electroweak symmetry breaking and physics beyond the standard model (SM). Since it was discovered more than one decade ago, measuring its properties is one of the most active fields. Most of the measured properties such as mass, width, production rate and so on are consistent with SM predictions, however the CDF and D0 Collaborations have observed a possible deviation on forward-backward (FB) asymmetry. At tt frame A FB is defined aswhere ∆Y ≡ Y t −Yt is the difference between rapidity of the top and antitop quark, which is invariant under tt or pp rest frame. of A FB in the MCFM is the cross section at the next leading order QCD, while the leading order cross section in Ref. [6][7][8]. Therefore they differ by a factor of k ∼ 1.3. Such FB asymmetry is equivalent to the charge asymmetry provided that CP is conserved. It is strange at first glance that vector like theory QCD can induce FB asymmetry. The fact is that such asymmetry arising from higher-order effects, namely, the interference between tree-level and virtual box diagrams of tt production, as well as among diagrams of real processes of qq → ttg (cf. Figs. 1-3). Similar asymmetry of QED was noticed even 37 years ago [9].Obviously only less than 3σ deviation is not the evidence that the SM is failed. Though the pursuit of possible new physics beyond the SM (BSM) implied by the deviation is exciting, the investigation of the same inference effect at more powerful Large Hadron Collider (LHC) is more necessary. Once the deviation is confirmed at the LHC, the measurements may be the first BSM signature. Unfortunately, the FB asymmetry defined at the proton-antiproton collider Tevatron is not applicable at the proton-proton collider LHC, as LHC does not have the preferred direction in the laboratory frame. In order to solve this issue, the central charge asymmetry has been proposed [6][7][8][10][11][12] Here A C is defined as the ratio between the difference and the sum of the events of the top and the antitop quark in a central region |Y | < Y C in the laboratory frame. The disadvantage of this definition is that at the LHC, such asymmetry is quite small. The reason is that the central region cut |Y | < Y C can not remove the symmetric tt events