Detecting a Higgs pseudoscalar with a Z boson produced in bottom quark fusion

We investigate the prospects of detecting a Higgs pseudoscalar (A0) in association with a Z gauge boson produced from bottom quark fusion (bb¯→ZA0) at the CERN Large Hadron Collider (LHC). A general two Higgs doublet model and the minimal supersymmetric standard model are adopted to study the discovery potential of pp→ZA0→ℓℓ¯bb¯+X,ℓ=e or μ, via bb¯→ZA0 with physics backgrounds and realistic cuts. Promising results are found for mA≲400GeV in a general two Higgs doublet model when the heavier Higgs scalar (H0) can decay into a Z boson and a Higgs pseudoscalar (H0→ZA0). We compare the production rates from bottom quark fusion (bb¯→ZA0) and gluon fusion (gg→ZA0), and find that they are complementary processes to produce ZA0 in hadron collisions. While gluon fusion is the major source for producing a Higgs pseudoscalar associated with a Z boson at the LHC for tanβ≲10, bottom quark fusion can make dominant contributions for tanβ≳10.