Probing anomalous Higgs couplings in H → ZV decays

We analyze the possibility of probing anomalous Higgs couplings in the rare decays H [Formula: see text] ZV, V being a vector quarkonium state. These rare decays involve both gauge as well as the Yukawa sectors and either of them can potentially be anomalous. We show that the branching fractions for H [Formula: see text] ZV decays in Standard Model (SM) are small, making it a sensitive probe for anomalous Higgs couplings originating from physics beyond SM. Moreover, as both V and Z can decay into pair of charged leptons, they provide experimentally clean channels and future LHC runs should observe such decays. We perform a model independent analysis and show how angular asymmetries can be used to probe these anomalous Higgs couplings, taking further decays of V and Z to pair of charged leptons into account. The angular asymmetries can provide significant information about anomalous Higgs couplings in both gauge and Yukawa sectors.

Quarkonia disintegration due to time dependence of the qq̄ potential in relativistic heavy-ion collisions

Rapid thermalization in ultra-relativistic heavy-ion collisions leads to fast changing potential between a heavy quark and antiquark from zero temperature potential to the finite temperature one. Time-dependent perturbation theory can then be used to calculate the survival probability of the initial quarkonium state. In view of very short time scales of thermalization at relativistic heavy-ion collider (RHIC) and large hadron collider (LHC) energies, we calculate the survival probability of [Formula: see text] and [Formula: see text] using sudden approximation. Our results show that quarkonium decay may be significant even when temperature of quark–gluon plasma (QGP) remains low enough so that the conventional quarkonium melting due to Debye screening is ineffective.