Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userT-odd correlations from CP violating anomalous top-quark couplings revisited
650
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
We revisit the effect of CP violating anomalous top-quark couplings in $tbar{t}$ production and decay. We consider $tbar{t}$ production through gluon fusion (and light $q{bar q}$ annihilation) followed by top-quark decay into $bW$ or $bell u$. We find explicit analytic expressions for all the triple products generated by the anomalous couplings that fully incorporate all spin correlations. Our results serve as a starting point for numerical simulations for the LHC.
rate research
Read More
We study the T odd correlations induced by CP violating anomalous top-quark couplings at both production and decay level in the process gg --> t t_bar --> (b mu+ nu_mu) (b_bar mu- nu_mu_bar). We consider several counting asymmetries at the parton level and find the ones with the most sensitivity to each of these anomalous couplings at the LHC.
In this talk, I review the T-odd correlations induced by CP violating anomalous top-quark couplings at both production and decay level in the process gg --> t t_bar --> (b mu+ nu_mu) (b_bar mu-nu_mu_bar). In addition I will also focus on experimental sensitivities corresponding to the anomalous couplings at the LHC.
We study the angular distribution of the charged lepton in the top-quark decay into a bottom quark and a W boson which subsequently decays into ell u_{ell}, when a hard gluon is radiated off. The absorptive part of the t to bWg decay amplitudes, which gives rise to T-odd asymmetries in the distribution, is calculated at the one-loop level in perturbative QCD. The asymmetries at a few percent level are predicted, which may be observable at future colliders.
We study a CP-violating triple product correlation that occurs in the decay of a neutral Higgs boson into tbar{t} pairs when the Higgs boson does not have a definite CP nature. We consider the H -> t bar{t} decay channel as well as the gluon fusion process gg -> H -> t bar{t}. The asymmetry in Higgs decay, normalized to the H -> t bar{t} width, can reach the 6% percent level. In the gluon fusion process the corresponding normalized asymmetry is smaller by an order of magnitude. We present a crude estimate of this observable at the LHC.
The effect of anomalous chromoelectric couplings of the gluon to the top quark are considered in e+ e- --> t tbar. The total cross section, as well as t and tbar polarizations are calculated to order alpha_s in the presence of the anomalous couplings. One of the two linear combinations of t and tbar polarizations is CP even, while the other is CP odd. Limits that could be obtained at a future linear collider on CP-odd combinations of anomalous couplings are determined.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
