The couplings of the electroweak effective theory contain information on the heavy-mass scales which are no-longer present in the low-energy Lagrangian. We build a general effective Lagrangian, implementing the electroweak chiral symmetry breaking SU(2) L ⊗ SU(2) R → SU(2) L+R , which couples the known particle fields to heavier states with bosonic quantum numbers J P = 0 ± and 1 ± . We consider colour-singlet heavy fields that are in singlet or triplet representations of the electroweak group. Integrating out these heavy scales, we analyze the pattern of low-energy couplings among the light fields which are generated by the massive states. We adopt a generic non-linear realization of the electroweak symmetry breaking with a singlet Higgs, without making any assumption about its possible doublet structure. Special attention is given to the different possible descriptions of massive spin-1 fields and the differences arising from naive implementations of these formalisms, showing their full equivalence once a proper short-distance behaviour is required.

Supplying global energy demand with CO2-free technologies is becoming feasible thanks to the rising affordability of renewable resources. Hydrogen is a promising vector in the decarbonization of energy systems, but more efficient and scalable synthesis is required to enable its widespread deployment. Here we report contactless H2 production via water electrolysis mediated by the microwavetriggered redox activation of solid-state ionic materials at low temperatures (<250 ºC). Water was reduced via reaction with non-equilibrium gadolinium-doped CeO2 that was previously in situ electrochemically deoxygenated by the sole application of microwaves. The microwave-driven reduction was identified by an instantaneous electrical conductivity rise and O2 release. This process was cyclable, whereas H2 yield and energy efficiency were material-and power-dependent. Deoxygenation of low-energy molecules (H2O or CO2) led to the formation of energy carriers and enabled CH4 production when integrated with a Sabatier reactor. This method could be extended to other reactions such as intensified hydrocarbons synthesis or oxidation.Sustainability of industry, transportation and energy management will rely on CO2-free technologies and renewable electricity, which are boosted by the rising affordability of photovoltaic solar and wind turbine parks. The electrification of industry and transport will strongly contribute to limiting greenhouse gas emissions 1,2 by using CO2-neutral energy carriers or chemical raw materials; however, the intermittent nature of renewables

The non-observation of new particles at the LHC suggests the existence of a mass gap above the electroweak scale. This situation is adequately described through a general electroweak effective theory with the established fields and Standard Model symmetries. Its couplings contain all information about the unknown short-distance dynamics which is accessible at low energies. We consider a generic strongly-coupled scenario of electroweak symmetry breaking, with heavy states above the gap, and analyze the imprints that its lightest bosonic excitations leave on the effective Lagrangian couplings. Different quantum numbers of the heavy states imply different patterns of low-energy couplings, with characteristic correlations which could be identified in future data samples. The predictions can be sharpened with mild assumptions about the ultraviolet behaviour of the underlying fundamental theory.

We analyze heavy states from generic ultraviolet completions of the Standard Model in a model-independent way and investigate their implications on the low-energy couplings of the electroweak effective theory. We build a general effective Lagrangian, implementing the electroweak symmetry breaking SU (2) L ⊗ SU (2) R → SU (2) L+R with a non-linear Nambu-Goldstone realization, which couples the known particles to the heavy states. We generalize the formalism developed in previous works [1,2] to include colored resonances, both of bosonic and fermionic type. We study bosonic heavy states with J P = 0 ± and J P = 1 ± , in singlet or triplet SU (2) L+R representations and in singlet or octet representations of SU (3) C , and fermionic resonances with J = 1 2 that are electroweak doublets and QCD triplets or singlets. Integrating out the heavy scales, we determine the complete pattern of low-energy couplings at the lowest non-trivial order. Some specific types of (strongly-and weakly-coupled) ultraviolet completions are discussed to illustrate the generality of our approach and to make contact with current experimental searches.

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Improvements in energy resolution of modern positron emission tomography (PET) detectors have created opportunities to implement energy-based scatter correction algorithms. Here, we use the energy information of auxiliary windows to estimate the scatter component. Our method is directly implemented in an iterative reconstruction algorithm, generating a scatter-corrected image without the need for sinograms. The purpose was to implement a fast energy-based scatter correction method on list-mode PET data, when it was not possible to use an attenuation map as a practical approach for the scatter degradation. The proposed method was evaluated using Monte Carlo simulations of various digital phantoms. It accurately estimated the scatter fraction distribution, and improved the image contrast in the simulated studied cases. We conclude that the proposed scatter correction method could effectively correct the scattered events, including multiple scatters and those originated in sources outside the field of view.

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Taking into account the negative results of direct searches for beyond the Standard Model fields and the consequent mass gap between Standard Model and possible unknown states, the use of electroweak effective theories is justified. Whereas at low energies we consider a non-linear realization of the electroweak symmetry breaking with a singlet Higgs and a strongly-coupled ultraviolet completion, at higher energies the known particles are assumed to be coupled to heavy states: bosonic fields with J P = 0 ± and J P = 1 ± (in electroweak triplets or singlets and in QCD octets or singlets) and fermionic states with J = 1 2 (in electroweak doublets and in QCD triplets or singlets). By integrating out these heavy resonances, the pattern of next-to-leading order lowenergy constants among the light fields can be studied. A phenomenological study trying to estimate the scale of these resonances is also shown.