71 research outputs found
Including the Fermion Vacuum Fluctuations in the flavor Polyakov Quark Meson Model
We consider the flavor Polyakov Quark Meson Model and study the
effect of including fermion vacuum fluctuations on the thermodynamics and phase
diagram. The resulting model predictions are compared to the recent QCD lattice
simulations by the HotQCD and Wuppertal-Budapest collaborations. The variation
of the thermodynamic quantities across the phase transition region becomes
smoother. This results in better agreement with the lattice data. Depending on
the value of the mass of the sigma meson, including the vacuum term results in
either pushing the critical end point into higher values of the chemical
potential or excluding the possibility of a critical end point altogether.Comment: 15 figures, some parts rewritten, new figures adde
Clockworking FIMPs
We study freeze-in dark matter production in models that rely on the
Clockwork mechanism to suppress the dark matter couplings to the visible
sector. We construct viable scalar and fermionic dark matter models within this
Clockwork FIMP scenario, with several subtleties that need to be taken into
account revealed in the model-building process. We also provide analytic,
semi-analytic and numerical results for the diagonalization of Clockwork-type
mass matrices and briefly discuss the LHC phenomenology of the corresponding
scenarios.Comment: 27 pages, 3 figures. Some typos in the appendices corrected. Accepted
for JHE
Lab-frame observables for probing the top-Higgs interaction
We investigate methods to explore the CP nature of the coupling
at the LHC, focusing on associated production of the Higgs with a
pair. We first discuss the constraints implied by low-energy observables and by
the Higgs-rate information from available LHC data, emphasizing that they
cannot provide conclusive evidence on the nature of this coupling. We then
investigate kinematic observables that could probe the coupling
directly, in particular quantities that can be constructed out of just
lab-frame kinematics. We define one such observable by exploiting the fact that
spin correlations do also carry information about the CP-nature of
the coupling. Finally, we introduce a CP-odd quantity and a
related asymmetry, able to probe CP violation in the coupling and
likewise constructed out of lab-frame momenta only.Comment: 32 pages, updated with latest data from ATLAS and references adde
Boosting Higgs CP properties via VH Production at the Large Hadron Collider
We consider ZH and WH production at the Large Hadron Collider, where the
Higgs decays to a bb pair. We use jet substructure techniques to reconstruct
the Higgs boson and construct angular observables involving leptonic decay
products of the vector bosons. These efficiently discriminate between the
tensor structure of the HVV vertex expected in the Standard Model and that
arising from possible new physics, as quantified by higher dimensional
operators. This can then be used to examine the CP nature of the Higgs as well
as CP mixing effects in the HZZ and HWW vertices separately.Comment: 5 pages, 3 figures. v2: two references added and typo correcte
Color Discriminant Variable to Separate Dijet Resonances at the LHC
A narrow resonance decaying to dijets could be discovered at the 14 TeV run
of the LHC. To quickly identify its color structure in a model-independent
manner, we introduced a method based on a color discriminant variable,
determined from the measurements of the resonance's production cross section,
mass and width. This talk introduces a more transparent theoretical formulation
of the color discriminant variable that highlights its relationship to the
branching ratios of the resonance into incoming and outgoing partons and to the
properties of those partons. The formulation makes it easier to predict the
value of the variable for a given class of resonance. We show that this method
applies well to color-triplet and color-sextet scalar diquarks, distinguishing
them clearly from other candidate resonances.Comment: 9 pages, 3 figures. Presentation at the DPF 2015 Meeting of the
American Physical Society Division of Particles and Fields, Ann Arbor,
Michigan, August 4-8, 201
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