Standard-model-like Higgs-pair production and decay in left-right twin Higgs model

In the framework of the left-right twin Higgs (LRTH) model, we study the production of a pair of SM-like Higgs bosons at the LHC (Higgs mass is typical in the range of 160-180 GeV). First, we examine the production rate and find that it can be significantly larger than the SM prediction. Then we investigate the decays of the Higgs-pair and find that in some parameter space the new decay mode hh→WWSˆSˆ (Sˆ is a candidate for WIMP dark matter) can be important, which can suppress sizably the conventional decay modes like hh→WWWW, hh→WWZZ and hh→WWbb¯. Finally, we study the promising channel gg→hh→WWWW and find that the rate can be sizably enhanced or suppressed compared with the SM prediction.