Unitarity constraints on ALP interactions

Unitarity constraints on asymmetric freeze-in

This paper considers unitarity and CPT constraints on asymmetric freeze-in, the use of freeze-in to store baryon number in a dark sector. In this scenario, Sakharov’s out of equilibrium condition is satisfied by placing the visible and hidden sectors at different temperatures while a net visible baryon number is produced by storing negative baryon number in a dark sector. It is shown that unita...

Unitarity constraints on chiral perturbative amplitudes

Low lying scalar resonances emerge as a necessary part to adjust chiral perturbation theory to experimental data once unitarity constraint is taken into consideration. I review recent progress made in this direction in a model independent approach. Also I briefly review studies on the odd physical properties of these low lying scalar resonances, including in the γγ → π+π−, π0π0 processes. Low l...

Unitarity constraints on meson wave functions.

Unitarity Constraints on Neutrino Mass and Mixings

Recent observations of atmospheric neutrinos and especially their zenithangle dependence , strongly suggest that muon neutrinos maximally mix with the tau neutrinos. Motivated by this observation and recent theoretical work on neutrino mass models , we explored 3 the implications of imposing the constraint that two neutrino flavors (which for definiteness we take to be νμ and ντ ) are similarly...

Unitarity Constraints on Anomalous Top Quark Couplings to Weak Gauge

If there is new physics associated with the top quark, it could show up as anomalous couplings of the top quark to weak gauge bosons, such as Ztt and Wtb vector and axial-vector couplings. We use the processes tt → ZZ, tt → W+W−, and tt → ZH to obtain the unitarity constraints on these anomalous couplings, and combine these constraints with those from precision electroweak data. The unitarity c...