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We report on a calculation of open heavy-flavor production at hadron colliders which extends to next-to-next-to-leading order (NNLO) accuracy the classic NLO-accurate formalism developed almost 30 years ago under the acronym FONLL. The approach retains the exact heavy-flavor mass dependence at low transverse momentum, $p_T$, and resums collinear logarithms through next-to-next-to-leading log (NNLL) at high $p_T$. Provided are predictions for $B$-hadrons as well as $B$-decay products like $J/\Psi$ and muons. The main features of the NNLO+NNLL results are reduced scale dependence and moderate NNLO correction, consistent with perturbative convergence in a wide range of kinematic scales from few GeV up to asymptotically large values of $p_T$. The new calculation significantly improves the agreement with data for $B$-hadrons and muons. We uncover an intriguing discrepancy in $J/\Psi$ final states which may point to a lower value of the $B\to J/\Psi$ decay rate., Comment: 7 pages, 5 figures

The problem of imaging materials with circular polarization properties is discussed within the framework of vectorial ptychography. We demonstrate, both theoretically and numerically, that using linear polarizations to investigate such materials compromises the unicity of the solution provided by this computational method. To overcome this limitation, an improved measurement approach is proposed, which involves specific combinations of elliptical polarizations. The effectiveness of this strategy is demonstrated by numerical simulations and experimental measurements on cholesteric liquid crystals films, which possess unique polarization properties. With the help of Pauli matrices algebra, our results highlight the technique's ability to discern between different types of circular polarizers, uniform vs. non-uniform, and determine their handedness.

We introduce HighTEA, a new paradigm for deploying fully-differential next-to-next-to leading order (NNLO) calculations for collider observables. In principle, any infrared safe observable can be computed and, with very few restrictions, the user has complete freedom in defining their calculation's setup. For example, one can compute generic n-dimensional distributions, can define kinematic variables and factorization/renormalization scales, and can modify the strong coupling and parton distributions. HighTEA operates on the principle of analyzing precomputed events. It has all the required hardware and software infrastructure such that users only need to request their calculation via the internet before receiving the results, typically within minutes, in the form of a histogram. No specialized knowledge or computing infrastructure is required to fully utilize HighTEA, which could be used by both experts in particle physics and the general public. The current focus is on all classes of LHC processes. Extensions beyond NNLO, or to $e^+e^-$ colliders, are natural next steps., Comment: 15 pages. HighTEA access and additional information: https://www.precision.hep.phy.cam.ac.uk/hightea/

In this work we perform the first ever calculation of jet event shapes at hadron colliders at next-to-next-to leading order (NNLO) in QCD. The inclusion of higher order corrections removes the shape difference observed between data and next-to-leading order predictions. The theory uncertainty at NNLO is comparable to, or slightly larger than, existing measurements. Except for narrow kinematical ranges where all-order resummation becomes important, the NNLO predictions for the event shapes considered in the present work are reliable. As a prime application of the results derived in this work we provide a detailed investigation of the prospects for the precision determination of the strong coupling constant and its running through TeV scales from LHC data., Comment: 24 pages, 9 figures, numerical results are provided here: https://www.precision.hep.phy.cam.ac.uk/results/hf-jets ; v2: updated references and acknowledgements, minor textual changes

State-of-the-art analyses of W+c-jet production at the LHC require precise predictions. In the present work, we study in detail the impact of off-diagonal CKM elements up to next-to-next-to leading order in QCD, the influence of flavored jet algorithms, and the size of electroweak corrections. In addition, we also investigate phenomenological aspects related to the exact definition of the process. We find that all these effects can be of the order of several per cent for both the fiducial cross section and differential distributions. They are, therefore, very relevant for the interpretation of current and upcoming measurements., Comment: 23 pages, 31 pdf Figures. Matches published version

In this work we derive three sets of non-perturbative fragmentation functions, with uncertainties, for $B$-hadrons, $J/\psi$'s and muons resulting from semileptonic $B$ decays. All three sets are with next-to-next-to leading order accuracy and include next-to-next-to leading logarithmic soft gluon resummation. The novel feature of these new sets is that they are fully consistent with our formalism for next-to-next-to leading order (NNLO) calculations for final states with identified $B$, $J/\psi$ or a $\mu$. We employ the fragmentation functions derived in this work to make state of the art predictions for such final states in $t\bar t$ events at the LHC. A special emphasis is placed on observables sensitive to the top quark mass. The present work opens the door for many LHC applications, like, open $B$ production or $B$ production in association with bosons., Comment: 46 pages, 59 figures, matches published version

Surface modification is an important topic to improve dental implants. Corundum residues, which are part of current dental implant blasting, disappeared on Straumann dental implants in recent publications. In our investigations of the surface of 4 different Straumann implants using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) we found the following three main findings: surfaces are nearly corundum-free, disseminated gap-framed corundum particles and significant molecular carbon residues. The data strongly suggest that Straumann applies a modified surface technology on dental implants to remove corundum residues and involving unclear carbons. One explanation could be, a Straumann patent involving a dextran coating allowing easy corundum particle removal by aqueous solution, while unintended molecular carbon residues cannot explain all findings. This change of the production process without a new approval by the FDA would be a violation of US federal law and the carbon bindings are a possible danger to patients., Comment: further information available on request

Recent experiments using 15 frame interferometry on PF-1000 facility in Warsaw confirm the association between neutron emission and spontaneously self-organized, relatively long lasting, finite plasma structures. A crucial aspect of this association is the simultaneous observation of an axial magnetic field, which can allow magnetic flux lines to densely cover closed surfaces creating "magnetic flux surfaces". Evolution of such 3-dimensional (3-D) magnetic field structures is necessarily accompanied by induced electric field that can provide a very long (theoretically infinite) acceleration path length along a trajectory enclosed within the magnetic structure leading to high ion kinetic energy, resulting in a high reaction rate. Associated charge and current densities can be related to electric scalar potential and magnetic vector potential measured outside the plasma. We report our first observations of these fields outside the plasma focus and discuss their general features. The reported technique is capable of unambiguous first-principles interpretation of signals in terms of quantities related to distributions of charge density and rate of change of azimuthal current density ("electromagnetic structure") in the plasma focus. It is non-intrusive and completely insensitive to non-axisymmetric aspects of plasma. Our first results show that axial magnetic field generated by azimuthal current density distribution symmetric about the axis exists before, during and after the pinch phase., Comment: Adapted from a paper presented at the 9th International International Workshop and Summer School on Plasma Physics, held at Kiten, Bulgaria on 7th July 2020

Contemporary insurance theory is concentrated on models with different types of polices and shock events may influence the payments on some of them. Jordanova (2018) considered a model where a shock event contributes to the total claim amount with one and the same value of the claim sizes to different types of polices. Jordanova and Veleva (2021) went a step closer to real-life situations and allowed a shock event to cause different claim sizes to different types of polices. In that paper, the counting process is assumed to be Multinomial. Here it is replaced with different independent homogeneous Poison processes. The bivariate claim counting process is expressed in two different ways. Its marginals and conditional distributions are totally described. The mean square regression of these processes is computed. The Laplace-Stieltjes transforms and numerical characteristics of the total claim amount processes are obtained. The risk reserve process and the probabilities of ruin in infinite time are discussed. The risk reserve just before the ruin and the deficit (or the severity) at ruin are thoroughly investigated in the case when the initial capital is zero. Their means, probability mass functions, and probability generating functions are obtained. Although the model is constructed by a multivariate counting process, along the paper it is shown that the total claim amount process is stochastically equivalent to a univariate compound Poisson process. These allow us to reduce the considered risk model to a Cramer-Lundberg risk model, to use the corresponding results, and to make the conclusions for the new model. Analogous results can be obtained for more types of polices and more types of shock events. The results are applied in case when the claim sizes are exponentially distributed. Stochastically equivalent models could be analogously constructed in queuing theory., Comment: The work is presented on Fourteenth Conference of the Euro-American Consortium for Promoting the Application of Mathematics in Technical and Natural Sciences, Albena, Bulgaria, June 22-27, 2022

Flavour tagging is technically challenging on the experimental side. However, it suffers from a more fundamental problem from the theoretical point of view, in particular when implemented in fixed-order perturbation theory. It turns out that an infrared-safe definition of a flavoured jet is intricate due to the singularities induced by the emission of flavoured quark-anti-quark pairs of negligible energy. Although this issue has been addressed by a modification of the standard $k_T$ jet algorithm, the situation is not entirely satisfactory as most measurements rather use the anti-$k_T$ jet algorithm. In this work, we propose a flavour-aware infrared-safe modification of the anti-$k_T$ jet algorithm that is easy to implement within perturbative Monte Carlo frameworks and has minor impact on jet phenomenology when flavour tagging is not required. Besides the numerical verification of the infrared safety of the proposed algorithm at next-to-next-to-leading order, we also present results for the hadro-production of a lepton pair in association with a $b$-jet, and of a top-quark pair decaying into $b$-jets and leptons., Comment: 21 pages, 26 figures

The International Linear Collider (ILC) is on the table now as a new global energy-frontier accelerator laboratory taking data in the 2030s. The ILC addresses key questions for our current understanding of particle physics. It is based on a proven accelerator technology. Its experiments will challenge the Standard Model of particle physics and will provide a new window to look beyond it. This document brings the story of the ILC up to date, emphasizing its strong physics motivation, its readiness for construction, and the opportunity it presents to the US and the global particle physics community., Comment: 356 pages, Large pdf file (40 MB) submitted to Snowmass 2021; v2 references to Snowmass contributions added, additional authors; v3 references added, some updates, additional authors

In these proceedings, we highlight some aspects of the recent computation of NNLO QCD corrections for W production in association with a charm jet at the LHC. The results are presented in the form of cross sections and differential distributions and are compared to ATLAS data., Comment: 6 pages, 5 pdf figures. Contribution to the Proceedings of RADCOR 2021 (15th International Symposium on Radiative Corrections: Applications of Quantum Field Theory to Phenomenology)

Multi-jet rates at hadron colliders provide a unique possibility for probing Quantum Chromodynamics (QCD), the theory of strong interactions. By comparing theory predictions with collider data, one can directly test perturbative QCD, extract fundamental parameters like the strong coupling $\alpha_s$ and search for physics beyond the Standard Model. In this work we calculate, for the first time, the next-to-next-to-leading (NNLO) QCD corrections to typical three-jet observables and to differential three-to-two jet ratios. We demonstrate that the inclusion of the NNLO corrections significantly reduces the dependence of those observables on the factorization and renormalization scales. Besides its phenomenological value, this proof-of-principle computation represents a milestone in perturbative QCD., Comment: 5 pages, 6 figures, In the original publication, we have evaluated the two-loop finite remainder function with an incorrect colour factor. The updated version of the paper contains the corrected plots and correspondingly updated statements in the text

We calculate the NNLO QCD corrections to diphoton production with an additional jet at the LHC. Our calculation represents the first NNLO-accurate prediction for the transverse momentum distribution of the diphoton system. The improvement in the accuracy of the theoretical prediction is significant, by a factor of up to four relative to NLO QCD. Our calculation is exact except for the finite remainder of the two-loop amplitude which is included at leading color. The numerical impact of this approximated contribution is small. The results of this work are expected to further our understanding of the Higgs boson sector and of the behavior of higher-order corrections to LHC processes., Comment: 12 pages, 7 figures

We calculate the complete set of two-loop leading-colour QCD helicity amplitudes for $\gamma \gamma j$-production at hadron colliders. Our results are presented in a compact, fully-analytical form., Comment: 13 pages, 1 figure, 3 tables, published version

We calculate, for the first time, the NNLO QCD corrections to identified heavy hadron production at hadron colliders. The calculation is based on a flexible numeric framework which allows the calculation of any distribution of a single identified heavy hadron plus jets and non-QCD particles. As a first application we provide NNLO QCD predictions for several differential distributions of $B$ hadrons in $t\bar t$ events at the LHC. Among others, these predictions are needed for the precise determination of the top quark mass. The extension of our results to other processes, like open or associated $B$ and charm production is straightforward. We also explore the prospects for extracting heavy flavor fragmentation functions from LHC data., Comment: 27 pages, 29 figures

We calculate all planar contributions to the two-loop massless helicity amplitudes for the process $q\bar q\to \gamma\gamma\gamma$. The results are presented in fully analytic form in terms of the functional basis proposed recently by Chicherin and Sotnikov. With this publication we provide the two-loop contributions already used by us in the NNLO QCD calculation of the LHC process $pp\to \gamma\gamma\gamma$ [Chawdhry et al. (2019)]. Our results agree with a recent calculation of the same amplitude [Abreu et al. (2020)] which was performed using different techniques. We combine several modern computational techniques, notably, analytic solutions for the IBP identities, finite-field reconstruction techniques as well as the recent approach [Chen (2019)] for efficiently projecting helicity amplitudes. Our framework appears well-suited for the calculation of two-loop multileg amplitudes for which complete sets of master integrals exist., Comment: 19 pages, 2 figures, published version

We study the production of a W boson in association with a c-jet at the LHC. We calculate, for the first time, the complete set of NNLO QCD corrections to the dominant CKM-diagonal contribution to this process. Both signatures, ${\rm p}{\rm p}\to \mu^+\nu_\mu{\rm j}_{\rm c}$ and ${\rm p}{\rm p}\to \mu^-\bar\nu_\mu{\rm j}_{\rm c}$ are considered. We present predictions for fiducial cross sections and differential distributions for each one of the two signatures as well as for their ratio. The theoretical predictions are compared with ATLAS measurements at $7 \; {\rm TeV}$. The results of this work are essential for the precision description of associated heavy flavor production at hadron colliders and for the determination of the strange-quark content of the proton from LHC data in NNLO QCD., Comment: 24 pages, 15 pdf figures

We present a joint extraction of the strong coupling $\alpha_s$ and the top-quark pole mass $m_t$ from measurements of top-quark pair production performed by the ATLAS and CMS experiments at the 8 TeV LHC. For the first time, differential NNLO theory predictions for different values of the top-quark mass are utilised for four kinematic distributions: the average transverse momentum of the top-quark, its average rapidity and the pair invariant mass and rapidity. The use of fastNLO tables for these distributions allows rapid evaluation of the differential theory predictions for different PDF sets. We consider the single differential distributions from the experiments both separately and in combination in order to obtain the best fit to theory. Our final values are $\alpha_s=0.1159^{+0.0013}_{-0.0014}$ and $m_t=173.8^{+0.8}_{-0.8}$ GeV which are compatible with previous extractions using top-quark measurements. In the case of $m_t$, our value is also compatible with the world average value collated by the Particle Data Group., Comment: 35 pages. Supplementary results available at http://www.precision.hep.phy.cam.ac.uk/results/ttbar-fastnlo/

We calculate a comprehensive set of spin correlations and differential distributions in top-quark pair production and decay to dilepton final states. This is the first time such a complete study is performed at next-to-next-to leading order in QCD. Both inclusive and fiducial distributions are presented and analyzed. Good agreement between NNLO QCD predictions and data is found. We demonstrate that it is possible to perform high-precision comparisons of fixed-order calculations with fiducial-level data. Subtleties of the top quark definition are raised and clarified. Some of those are found to have a very significant impact on top-quark pair production at absolute threshold., Comment: 49 pages, 94 figures, published version, minor changes in the figures and text

LHC $t\bar{t}$ data have the potential to provide constraints on the gluon distribution, especially at high $x$, with both ATLAS and CMS performing differential measurements. Recently, CMS has measured double-differential $t\bar{t}$ distributions at 8 TeV. In this paper we examine the impact of this data set on the gluon distribution. To that end we develop novel, double-differential NNLO predictions for that data. No significant impact is found when the CMS data is added to the CT14HERA2 global PDF fit, due to the larger impact of the inclusive jet data from both the Tevatron and the LHC. If the jet data are removed from the fit, then an impact is observed. If the CMS data is scaled by a larger weight, representing the greater statistical power of the jet data, a roughly equal impact on the gluon distribution is observed for the $t\bar{t}$ as for the inclusive jet data. For data samples with higher integrated luminosity at 13 TeV, a more significant impact of the double-differential $t\bar{t}$ data may be observed., Comment: 31 pages,22 figures, 6 tables

We compute the NNLO QCD corrections to three-photon production at the LHC. This is the first NNLO QCD calculation for a $2\to 3$ process. Our calculation is exact, except for the scale-independent part of the two-loop finite remainder which is included in the leading color approximation. We estimate the size of the missing two-loop corrections and find them to be phenomenologically negligible. We compare our predictions with available 8 TeV measurement from the ATLAS collaboration. We find that the inclusion of the NNLO corrections eliminates the existing significant discrepancy with respect to NLO QCD predictions, paving the way for precision phenomenology in this process., Comment: 20 pages, 6 figures. v2: published version

Detailed studies have been carried out on the impact of the LHC top quark pair production data on gluon PDF, in the context of the CTEQ-TEA global PDF fit, with the ePump-updating method. The considered $t\bar{t}$ data include single differential distributions from ATLAS and double differential distributions from CMS, both at 8 TeV. All analyses have been carried out at the NNLO, using fastNNLO tables. We show that the sensitivity per data point of the LHC $t\bar{t}$ data is similar to that of jet data, as included in the CT14HERA2 fit, while the total sensitivity of the present $t\bar{t}$ data is not as large as the jet data because of the much smaller number of $t\bar{t}$ data points in the presently available data.

Next-to-next-to-leading order QCD predictions for single-, double- and even triple-differential distributions of jet events in proton-proton collisions have recently been obtained using the NNLOjet framework based on antenna subtraction. These results are an important input for Parton Distribution Function fits to hadron-collider data. While these calculations include all of the partonic channels occurring at this order of the perturbative expansion, they are based on the leading-color approximation in the case of channels involving quarks and are only exact in color in the pure-gluon channel. In the present publication, we verify that the sub-leading color effects in the single-jet inclusive double-differential cross sections are indeed negligible as far as phenomenological applications are concerned. This is the first independent and complete calculation for this observable. We also take the opportunity to discuss the necessary modifications of the sector-improved residue subtraction scheme that made this work possible., Comment: 42 pages, 3 figures, v2 (published version) minor changes

In any calculation in perturbative Quantum Chromodynamics (QCD) a choice needs to be made for the unphysical renormalisation scale, $\mu_R$. The Brodsky-Lepage-Mackenzie/Principle of Maximum Conformality (BLM/PMC) scale-setting procedure is one proposed method for selecting this scale. In this work we identify three ambiguities in the BLM/PMC procedure itself. Their numerical impact is studied using the example of the total cross-section for $t\bar{t}$ production through Next-to-Next-to-Leading Order in QCD. One ambiguity is the arbitrary choice of the value of the highest-order PMC scale. The numerical impact of this choice on the BLM/PMC prediction for the cross-section is found to be comparable to the impact of the choice of $\mu_R$ in the conventional scale-setting approach. Another ambiguity relates to the definitions of the other PMC scales and is similarly found to have a large impact on the cross-section., Comment: 8 pages, 2 figures, 8 tables. v2 (published version): added references and changed title

We present a supervised approach for style change detection, which aims at predicting whether there are changes in the style in a given text document, as well as at finding the exact positions where such changes occur. In particular, we combine a TF.IDF representation of the document with features specifically engineered for the task, and we make predictions via an ensemble of diverse classifiers including SVM, Random Forest, AdaBoost, MLP, and LightGBM. Whenever the model detects that style change is present, we apply it recursively, looking to find the specific positions of the change. Our approach powered the winning system for the PAN@CLEF 2018 task on Style Change Detection., Comment: Accepted as regular paper at AIMSA 2018

The successful operation of the Large Hadron Collider (LHC) and the excellent performance of the ATLAS, CMS, LHCb and ALICE detectors in Run-1 and Run-2 with $pp$ collisions at center-of-mass energies of 7, 8 and 13 TeV as well as the giant leap in precision calculations and modeling of fundamental interactions at hadron colliders have allowed an extraordinary breadth of physics studies including precision measurements of a variety physics processes. The LHC results have so far confirmed the validity of the Standard Model of particle physics up to unprecedented energy scales and with great precision in the sectors of strong and electroweak interactions as well as flavour physics, for instance in top quark physics. The upgrade of the LHC to a High Luminosity phase (HL-LHC) at 14 TeV center-of-mass energy with 3 ab$^{-1}$ of integrated luminosity will probe the Standard Model with even greater precision and will extend the sensitivity to possible anomalies in the Standard Model, thanks to a ten-fold larger data set, upgraded detectors and expected improvements in the theoretical understanding. This document summarises the physics reach of the HL-LHC in the realm of strong and electroweak interactions and top quark physics, and provides a glimpse of the potential of a possible further upgrade of the LHC to a 27 TeV $pp$ collider, the High-Energy LHC (HE-LHC), assumed to accumulate an integrated luminosity of 15 ab$^{-1}$., Comment: Report from Working Group 1 on the Physics of the HL-LHC, and Perspectives at the HE-LHC

We describe predictions for top-quark pair differential distributions at hadron colliders, which combine state-of-the-art NNLO QCD calculations and NLO electroweak corrections together with double resummation at NNLL$'$ accuracy of threshold logarithms and small-mass logarithms. This is the first time that such a combination has appeared in the literature. Numerical results are presented for the invariant-mass distribution, the transverse-momentum distribution as well as rapidity distributions., Comment: Contribution to the proceedings of the 11th International Workshop on Top Quark Physics (TOP2018); v3: significantly modified version with more numeric results

We calculate, for the first time, the next-to-next-to leading order (NNLO) QCD corrections to spin correlations in top quark pair production at the LHC. The NNLO corrections play an important role in the description of the corresponding differential distributions. We observe that the Standard Model calculation describes the available delta-phi data in the fiducial region but does not agree with the delta-phi measurement extrapolated to full phase space. Most likely this discrepancy is due to the difference in precision between existing event generators and NNLO calculations for dilepton top-pair final states., Comment: 6 pages, 5 figures

In this proceedings we compare phenomenological predictions for differential distributions in top-quark pair production at the LHC. In particular we consider NNLO QCD fixed-order predictions and parton-level predictions based on NLO QCD multi-jet merging following the MEPS@NLO scheme. In both predictions NLO electroweak (EW) corrections are incorporated in different approximations. We focus on several transverse-momentum distributions and on the top-quark invariant mass distribution, both highly relevant for the ongoing physics program at the LHC. We discuss comparisons between the different considered approximations and their advantages and disadvantages for different distributions., Comment: 5 pages plus references, 3 figures, Proceedings of the 11th International Workshop on Top Quark Physics, Bad Neuenahr, Germany, September 2018

The Compact Linear Collider (CLIC) is a mature option for the future of high energy physics. It combines the benefits of the clean environment of $e^+e^-$ colliders with operation at high centre-of-mass energies, allowing to probe scales beyond the reach of the Large Hadron Collider (LHC) for many scenarios of new physics. This places the CLIC project at a privileged spot in between the precision and energy frontiers, with capabilities that will significantly extend knowledge on both fronts at the end of the LHC era. In this report we review and revisit the potential of CLIC to search, directly and indirectly, for physics beyond the Standard Model., Comment: 282 pages, 128 Figures, 55 Tables and 732 citations. Editors: J. de Blas, R. Franceschini, F. Riva, P. Roloff, U. Schnoor, M. Spannowsky, J. D. Wells, A. Wulzer and J. Zupan. Version published in CERN Yellow Report Monographs