Irrotational dust with Div H=0

For irrotational dust the shear tensor is consistently diagonalizable with its covariant time derivative: $\sigma_{ab}=0=\dot{\sigma}_{ab},\; a\neq b$, if and only if the divergence of the magnetic part of the Weyl tensor vanishes: $div~H = 0$. We show here that in that case, the consistency of the Ricci constraints requires that the magnetic part of the Weyl tensor itself vanishes: $H_{ab}=0$.Comment: 19 pages. Latex. Also avaliable at http://shiva.mth.uct.ac.za/preprints/text/lesame2.te

Exotic Higgs Decay via Charged Higgs

The most common search channel for heavy neutral Higgses in models with an extension of the Standard Model Higgs sector is $A/H^0\rightarrow \tau\tau$, which becomes ineffective when new decay modes of $A/H^0$ open. In this paper, we analyzed two such channels involving charged Higgses in the final states: $A/H^0 \rightarrow W^\pm H^\mp$ and $H^0 \rightarrow H^+H^-$. With the consequent decay of $H^\pm\rightarrow \tau\nu$, we found that the limits for $\sigma\times{BR}(gg \rightarrow A/H^0 \rightarrow W^\pm H^\mp)\times {BR}(H^\pm \rightarrow \tau \nu)$ vary from 30 to 10 fb for $m_{A/H^0}$ between 300 and 1000 GeV for 95% C.L. exclusion, and about 80 to 30 fb for 5$\sigma$ discovery. For $H^+H^-$ mode, 95% C.L. limits on $\sigma\times {BR}(gg\to H^0\to H^+ H^-)\times {BR}^2(H^\pm\to \tau\nu)$ vary from 9 to 4 fb for $m_{H^0}$ between 400 and 1000 GeV, while the 5$\sigma$ reach is about 20 to 10 fb. We further interpret the cross section limits in the Type II 2HDM parameter space. While $A\rightarrow W^\pm H^\mp$ offers great sensitivity in both $\sin(\beta-\alpha)$ versus $\tan\beta$ and $m_A$ versus $\tan\beta$ parameter space, $H^0\rightarrow H^+ H^-$ can cover most of the parameter space for $H^0$. Reach in $H^0\rightarrow W^\pm H^\mp$ is more limited, especially for $m_{H^0}>2 m_{H^\pm}$. It is, however, complementary to $H^0\rightarrow H^+ H^-$ when ${BR}(H^0\rightarrow H^+ H^-)$ is accidentally suppressed.Comment: 19 pages, 11 figures, version appear in JHE

Higgs-photon resonances

We study models that produce a Higgs boson plus photon ($h^0 \gamma$) resonance at the LHC. When the resonance is a $Z'$ boson, decays to $h^0 \gamma$ occur at one loop. If the $Z'$ boson couples at tree-level to quarks, then the $h^0 \gamma$ branching fraction is typically of order $10^{-5}$ or smaller. Nevertheless, there are models that would allow the observation of $Z' \to h^0 \gamma$ at $\sqrt{s} = 13$ TeV with a cross section times branching fraction larger than 1 fb for a $Z'$ mass in the 200--450 GeV range, and larger than 0.1 fb for a mass up to 800 GeV. The 1-loop decay of the $Z'$ into lepton pairs competes with $h^0 \gamma$, even if the $Z'$ couplings to leptons vanish at tree level. We also present a model in which a $Z'$ boson decays into a Higgs boson and a pair of collimated photons, mimicking an $h^0 \gamma$ resonance. In this model, the $h^0 \gamma$ resonance search would be the discovery mode for a $Z'$ as heavy as 2 TeV. When the resonance is a scalar, although decay to $h^0 \gamma$ is forbidden by angular momentum conservation, the $h^0$ plus collimated photons channel is allowed. We comment on prospects of observing an $h^0 \gamma$ resonance through different Higgs decays, on constraints from related searches, and on models where $h^0$ is replaced by a nonstandard Higgs boson.Comment: 22 page

chi_cJ Decays to h^+h^-h^0

Using a sample of 3x10^6 psi(2S) decays recorded by the CLEO detector, we study three body decays of the chi_{c0}, chi_{c1}, and chi_{c2} produced in radiative decays of the psi(2S). We consider the decay modes pi+ pi- eta, K+ K- eta, p pbar eta, pi+ pi- etaprime, K+ K- pi0, p pbar pi0, pi+ K- K0S, and K+ pbar Lambda measuring branching fractions or placing upper limits. For chi_{c1} to pi+ pi- eta, K+ K- pi0, and pi+ K- K0S our observed samples are large enough to study the substructure in a Dalitz plot analysis. The results presented in this document are preliminary.Comment: 22 pages postscript,also available through http://www.lepp.cornell.edu/public/CONF/2006, Contributed to ICHEP0