Probing top-partners in Higgs + jets

Fermionic top-partners arise in models such as Composite Higgs and Little Higgs. They modify Higgs properties, in particular how the Higgs couples to top quarks. Alas, there is a low-energy cancellation acting in the coupling of the Higgs boson to gluons and photons. As a result of this cancellation, no information about the spectrum and couplings of the top-partners can be obtained in gluon fusion to Higgs, just the overall new physics scale. In this paper we show that this is not the case when hard radiation is taken into account. Indeed, differential distributions in Higgs plus jets are sensitive to the top-partner mass and coupling to the Higgs. We exploit the transverse momentum distribution of the hard jet to obtain limits on the top-partners in the 14 TeV LHC run, finding that 300 ifb of data of 14 TeV LHC are sufficient to rule out top-sector mixing angles $\sin^2 (\theta_R)$ > 0.05 for top-partners with masses from 300 GeV to above 2 TeV.Comment: 23 pages, 11 figure

Describing viable technicolor scenarios

We construct an effective Lagrangian for new strong interactions at the LHC, including as a first step the two lightest triplets of spin-1 resonances. Our parametrization is general enough to allow for previously unstudied spectrum and couplings. Among available frameworks to describe the spin-1 sector, we rely on an extra-dimensional description. Our approach limits the number of parameters yet is versatile enough to describe the phenomenology of a wide range of new scenarios of strong electroweak symmetry breaking

On the impact of dimension-eight SMEFT operators on Higgs measurements

Using the production of a Higgs boson in association with a $W$ boson as a test case, we assess the impact of dimension-8 operators within the context of the Standard Model Effective Field Theory. Dimension-8--SM-interference and dimension-6-squared terms appear at the same order in an expansion in $1/\Lambda$, hence dimension-8 effects can be treated as a systematic uncertainty on the new physics inferred from analyses using dimension-6 operators alone. To study the phenomenological consequences of dimension-8 operators, one must first determine the complete set of operators that can contribute to a given process. We accomplish this through a combination of Hilbert series methods, which yield the number of invariants and their field content, and a step-by-step recipe to convert the Hilbert series output into a phenomenologically useful format. The recipe we provide is general and applies to any other process within the dimension $\le 8$ Standard Model Effective Theory. We quantify the effects of dimension-8 by turning on one dimension-6 operator at a time and setting all dimension-8 operator coefficients to the same magnitude. Under this procedure and given the current accuracy on $\sigma(pp \to h\,W^+)$, we find the effect of dimension-8 operators on the inferred new physics scale to be small, $\mathcal O(\text{few}\,\%)$, with some variation depending on the relative signs of the dimension-8 coefficients and on which dimension-6 operator is considered. The impact of the dimension-8 terms grows as $\sigma(pp \to h\,W^+)$ is measured more accurately or (more significantly) in high-mass kinematic regions. We provide a FeynRules implementation of our operator set to be used for further more detailed analyses.Comment: More operator coefficient choices explored, bugs in FeynRules implementation correcte

Real Convergence and European Integration: The Experience of the Less Developed EU Members

This study aims at providing an assessment about real convergence across countries and regions in the EU, focusing more specifically on the four cohesion EU members (Spain, Portugal, Ireland and Greece), since they seem to be more appropriate to draw lessons for the Central and Eastern European countries (CEECs). The results obtained when making an assessment of real convergence in the EU, both at country and regional level, show that in the course of the last few years a process of convergence has taken place between the per capita income levels of the EU regions and also, to a larger extent, of the Member States. Nevertheless, also marked differences could be identified: Ireland is undoubtedly the most successful of the four, while Greece showed the least satisfactory performance. In this respect, the differences that may be observed between these countries suggest that advances in real convergence are far from being a spontaneous outcome of the accession to the EU, but largely determined by the growth strategy implemented by the countries themselves. Lastly, our study suggests that the Communitys regional policy has played a significant role in favor of real convergence between the Member States of the EU. However, the experience of Greece indicates that the impact of EUs financial assistance on the beneficiary countries depends not only on its amount, but also on the efficiency with which its allocation is carried out. One important lesson to be drawn is that the accession is likely to contribute significantly to improving the possibilities of the current CEECs candidates in aligning their per capita income levels with those of the more advanced current EU members. However, we have also learnt that the prospects of growth and income convergence towards EU levels in the current candidates will depend crucially on the measures taken by each country, and particularly on their capacity to invest more and more efficiently

Digital-analog co-design of the Harrow-Hassidim-Lloyd algorithm

The Harrow-Hassidim-Lloyd quantum algorithm was proposed to solve linear systems of equations $A\vec{x} = \vec{b}$ and it is the core of various applications. However, there is not an explicit quantum circuit for the subroutine which maps the inverse of the problem matrix $A$ into an ancillary qubit. This makes challenging the implementation in current quantum devices, forcing us to use hybrid approaches. Here, we propose a systematic manner to implement this subroutine, which can be adapted to other functions $f(A)$ of the matrix $A$, we present a co-designed quantum processor which reduces the depth of the algorithm, and we introduce its digital-analog implementation. The depth of our proposal scales with the precision $\epsilon$ as $\mathcal{O}(\epsilon^{-1})$, which is bounded by the number of samples allowed for a certain experiment. The co-design of the Harrow-Hassidim-Lloyd algorithm leads to a "kite-like" architecture, which allows us to reduce the number of required SWAP gates. Finally, merging a co-design quantum processor architecture with a digital-analog implementation contributes to the reduction of noise sources during the experimental realization of the algorithm.Comment: 7 pages, 3 figure

Polarization of the WMAP Point Sources

The detection of polarized sources in the WMAP 5-year data is a very difficult task. The maps are dominated by instrumental noise and only a handful of sources show up as clear peaks in the Q and U maps. Optimal linear filters applied at the position of known bright sources detect with a high level of significance a polarized flux P from many more sources, but estimates of P are liable to biases. Using a new technique, named the "filtered fusion technique", we have detected in polarization, with a significance level greater than 99.99% in at least one WMAP channel, 22 objects, 5 of which, however, do not have a plausible low radio frequency counterpart and are therefore doubtful. Estimated polarized fluxes P < 400 mJy at 23 GHz were found to be severely affected by the Eddington bias. The corresponding polarized flux limit for Planck/LFI at 30 GHz, obtained via realistic simulations, is 300 mJy. We have also obtained statistical estimates of, or upper limits to the mean polarization degrees of bright WMAP sources at 23, 33, 41, and 61 GHz, finding that they are of a few percent.Comment: 10 pages, 6 figures. Accepted for publication in Ap