arXiv subjects

Arild Skjold

Publications and source records attributed to Arild Skjold.

6 recordsLinked to original sources

arXiv1995

CP Investigations in the Higgs Sector

In a more general electroweak theory, there could be Higgs particles that are odd under $CP$. When such particles decay via vector bosons to two fermion-antifermion pairs, the momenta of those will be correlated in a way which is determined by the $CP$ of the particle. Similarly, in the Bjorken process correlations among momenta of the initial electron and final-state fermions are sensitive to the $CP$ quantum number. Monte Carlo data on the expected efficiency demonstrate that it should be possible to verify the scalar character of an intermediate-mass Standard Model Higgs boson after three years of data taking at a future linear collider. This is most likely not possible at LEP2. Signals of possible presence of $CP$ violation in the Higgs sector are briefly discussed.

hep-ph↗

arXiv1995

Determining the CP of a Higgs Particle at a Future Linear Collider

In a more general electroweak theory, there could be Higgs particles that are odd under $CP$. Correlations among momenta of the initial electron and final-state fermions are in the Bjorken process sensitive to the $CP$ parity. Monte Carlo data on the expected efficiency demonstrate that it should be possible to verify the scalar character of an intermediate-mass Standard Model Higgs boson after three years of data taking at a future linear collider. This is most likely not possible at LEP2. Signals of possible presence of $CP$ violation in the Higgs sector are briefly discussed.

hep-ph↗

arXiv1995

Testing $CP$ in the Bjorken process

In a more general electroweak theory, there could be Higgs particles that are odd under $CP$, and also Higgs-like particles which are not eigenstates of $CP$. We discuss distributions which for the Bjorken process are sensitive to the $CP$ parity. Correlations among momenta of the initial electron and final-state fermions yield this kind of information. We discuss also observables which may demonstrate presence of $CP$ violation and identify a phase shift $δ$ which is a measure of the strength of $CP$ violation in the Higgs-vector-vector coupling, and which can be measured directly in the decay distribution. We present Monte Carlo data on the expected efficiency, and conclude that it is relatively easy to determine whether the produced particle is even or odd under $CP$. However, observation of any $CP$ violation would require a very large amount of data.

hep-ph↗

arXiv1994

Probing CP in the Higgs Sector

We discuss how one may determine whether some Higgs particle is an eigenstate of $CP$ or not, and if so, how we may probe whether it is $CP$-odd or $CP$-even. The idea is applied to Higgs decay where correlations among momenta of the decay products may yield the desired information. These are correlations of decay planes defined by the momenta of pairs of particles as well as correlations between energy differences. In the case that the Higgs particle is an eigenstate of $CP$, our study includes finite-width effects. The correlations between energy differences turn out to be a much better probe for investigating $CP$ properties than the previously suggested angular correlations, especially for massive Higgs bosons.

hep-ph↗

arXiv1994

Signals of $CP$ violation in Higgs decay

We consider an extension of the Standard Model where some Higgs particle is not an eigenstate of $CP$, and discuss the possibility of extracting signals of the resulting $CP$ violation. In the case of Higgs decay to four fermions we study correlations among momenta of the final-state fermions. We discuss observables which may demonstrate presence of $CP$ violation and identify a phase shift $δ$, which is a measure of the strength of $CP$ violation in the Higgs-vector-vector coupling, and which can be measured directly in the decay distribution. In addition to these angular correlations, we consider correlations between energy differences. The former correlations include some recently reported results, whereas the latter ones appear to provide a much better probe for revealing $CP$ violation.

hep-ph↗

arXiv1993

Angular and energy correlations in Higgs decay

We discuss how correlations among momenta of the decay products may yield information about the CP-parity of the Higgs particle. These are correlations of decay planes defined by the momenta of pairs of particles as well as correlations between energy differences. Our study includes finite-width effects. In the narrow-width approximation the angular correlations coincide with previously reported results. The correlations between energy differences turn out to be a much better probe for CP determination than the previously suggested angular correlations, especially for massive Higgs bosons.

hep-ph↗