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202 results on '"German Valencia"'

1. Scalar dark matter explanation of the excess in the Belle II B + → K ++ invisible measurement

Author: Xiao-Gang He, Xiao-Dong Ma, Michael A. Schmidt, German Valencia, and Raymond R. Volkas
Subjects: Models for Dark Matter, Rare Decays, Vector-Like Fermions, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: Abstract Recently Belle II reported the first measurement of B + → K + + invisible(inv), which is 2.7σ above the standard model (SM) prediction. If confirmed, this calls for new physics beyond SM. In the SM, the invisible particles are neutrino-anti-neutrino pairs. There are more possibilities when going beyond the SM. In this work, we focus on decays to dark matter (DM) and show that the B → K + inv excess from Belle II and DM relic density can be simultaneously explained in a simple extension of the SM. The model introduces a real scalar singlet ϕ acting as a DM candidate, and two heavy vector-like quarks Q, D with the same quantum numbers as the SM left-handed quark doublet and right-handed down-type quark singlet, respectively. All these new particles are odd under a ℤ2 symmetry while the SM particles are even. The model can successfully explain the Belle II anomaly and DM relic density for TeV-scale heavy quarks with hierarchical Yukawa couplings involving b and s quarks. At the same time, it can easily satisfy other flavour physics constraints. Direct detection searches utilizing the Migdal effect constrain some of the parameter space.
Published: 2024
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2. FCNC B and K meson decays with light bosonic Dark Matter

Author: Xiao-Gang He, Xiao-Dong Ma, and German Valencia
Subjects: New Light Particles, Rare Decays, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: Abstract We consider decays of B and K mesons into a pseudo-scalar or vector meson plus missing energy. Within the SM, these modes originate from flavor changing neutral current (FCNC) processes with two neutrinos in the final state. In this paper we consider the experimental upper bounds on these modes and interpret the difference between these bounds and the SM prediction as a window into new light invisible particles. In particular we consider the case where some new symmetry requires the new particles to be produced in pairs. We first construct the general low energy effective Lagrangian coupling an FCNC with two dark sector particles of spin zero, one-half and one. We then present numerical estimates for the constraints that can be placed on these interactions, finding that an effective new physics scale from O $$ \mathcal{O} $$ (10)- O $$ \mathcal{O} $$ (1011) GeV can be probed, with the exact value strongly depending on the interaction structure as well as the mass of the invisible particle. For we incorporate into our constraints the effect of using only the signal regions of NA62, and for the q 2-dependent efficiency of Belle II.
Published: 2023
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3. Complementarity of μTRISTAN and Belle II in searches for charged-lepton flavour violation

Author: Gabriela Lichtenstein, Michael A. Schmidt, German Valencia, and Raymond R. Volkas
Subjects: Physics, QC1-999
Abstract: We analyse the potential of the proposed μ+μ+ and μ+e− collider μTRISTAN to complement the searches for charged-lepton flavour-violation (CLFV) that can be carried out by Belle II. μTRISTAN offers the possibility of directly producing and studying new resonances that could mediate CLFV for a certain range of masses. In addition, we find that it can produce competitive bounds to those from Belle II for cases where the new resonance lies beyond direct reach. We illustrate these points with three Z3 “lepton triality” models, where we also find an example that can only be probed by μTRISTAN. These three models feature doubly-charged scalars, denoted k1,2,3 respectively, that induce both CLFV and flavour-conserving processes. Tree-level k1 exchange induces the CLFV scattering process μ+e−→e+τ−, while k2 interactions induce μ+μ+→τ+e+, μ+e−→τ+μ− and make a non-SM contribution to the flavour-conserving scattering μ+μ+→μ+μ+. The k3 model has a non-SM contribution to the flavour-conserving process μ+e−→μ+e−. Other scattering processes involving k1, k2 or k3 are not relevant for μTRISTAN and outside the scope of our analysis. We quantify the sensitivity of μTRISTAN for each of these processes. For the k1 and k2 cases we compare the μTRISTAN reach to the expected sensitivity of Belle II to the crossing symmetry related CLFV τ decays.
Published: 2023
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4. LHC constraints on $$W^\prime ,~Z^\prime $$ W ′ , Z ′ that couple mainly to third generation fermions

Author: Alper Hayreter, Xiao-Gang He, and German Valencia
Subjects: Astrophysics, QB460-466, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: Abstract We use the results of CMS and ATLAS searches for resonances that decay to $$\tau \nu $$ τ ν or tb and $$\tau ^+\tau ^-$$ τ + τ - or $$t{\bar{t}}$$ t t ¯ final states to constrain the parameters of non-universal $$W^\prime $$ W ′ and $$Z^\prime $$ Z ′ gauge bosons that couple preferentially to the third generation. For the former we consider production from $$c\bar{b}$$ c b ¯ annihilation and find very weak constraints on the strength of the interaction and only for the mass range between 800 and 1100 GeV from the $$pp \rightarrow \tau _h p_T^{\mathrm{miss}}$$ p p → τ h p T miss channel. The constraints on the latter are much stronger and arise from both $$t{\bar{t}}$$ t t ¯ and $$\tau ^+\tau ^-$$ τ + τ - production. Treated separately, we find that the weak constraints on the $$W^\prime $$ W ′ still permit an explanation of the $$R(D^{(\star )})$$ R ( D ( ⋆ ) ) anomalies with a light sterile neutrino whereas the stronger constraints on the $$Z^\prime $$ Z ′ exclude significant light sterile neutrino contributions to the $$K \rightarrow \pi \nu \bar{\nu }$$ K → π ν ν ¯ rates. Within specific models the masses of $$W^\prime $$ W ′ and $$Z^\prime $$ Z ′ are of course related and we briefly discuss the consequences.
Published: 2020
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5. Evading the Grossman-Nir bound with ∆I = 3/2 new physics

Author: Xiao-Gang He, Xiao-Dong Ma, Jusak Tandean, and German Valencia
Subjects: Beyond Standard Model, Chiral Lagrangians, Effective Field Theories, Kaon Physics, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: Abstract Rare kaon decays with missing energy, K → π+E miss, have received considerable attention because their rates can be calculated quite precisely within the standard model (SM), where the missing energy is carried away by an undetected neutrino- antineutrino pair. Beyond the SM, clean theoretical predictions can also be made regarding these processes. One such prediction is the so-called Grossman-Nir (GN) bound, which states that the branching fractions of the K L and K + modes must satisfy the relation ℬ K L → π 0 + E miss < ∼ 4.3 ℬ K + → π + + E miss $$ \mathrm{\mathcal{B}}\left({K}_L\to {\pi}^0+{E}_{\mathrm{miss}}\right)\underset{\sim }{
Published: 2020
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6. Breaking the Grossman-Nir bound in kaon decays

Author: Xiao-Gang He, Xiao-Dong Ma, Jusak Tandean, and German Valencia
Subjects: Beyond Standard Model, CP violation, Kaon Physics, Neutrino Physics, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: Abstract The ratio ℬ K L → π 0 v v ¯ / ℬ K + → π + v v ¯ $$ \mathrm{\mathcal{B}}\left({K}_L\to {\pi}^0v\overline{v}\right)/\mathrm{\mathcal{B}}\left({K}^{+}\to {\pi}^{+}v\overline{v}\right) $$ of the branching fractions of kaon decays K L → π 0 v v ¯ $$ {K}_L\to {\pi}^0v\overline{v} $$ and K + → π + v v ¯ $$ {K}^{+}\to {\pi}^{+}v\overline{v} $$ has a maximum of about 4.3 under the assumption that the underlying interactions change isospin by ∆I = 1/2. This is referred to as the Grossman-Nir (GN) bound, which is respected by the standard model (SM) and by many scenarios beyond it. Recent preliminary results of the KOTO and NA62 Collaborations searching for these kaon modes seem to imply a violation of this bound. The KOTO findings also suggest that ℬ K L → π 0 v v ¯ $$ \mathrm{\mathcal{B}}\left({K}_L\to {\pi}^0v\overline{v}\right) $$ could be much larger, by nearly two orders of magnitude, than that predicted in the SM. In this work we study the possibility of violating the GN bound in an effective field theory approach with only SM fields. We show that the bound holds, in addition to the original GN scenarios, whether or not the kaon decays conserve lepton number. We demonstrate that the inclusion of ∆I = 3/2 operators can lead to a violation of the GN bound and illustrate with an example of how the KOTO numbers may be reached with a new physics scale of order tens of GeV.
Published: 2020
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7. RK(⁎)ν and non-standard neutrino interactions

Author: Xiao Gang He and German Valencia
Subjects: Physics, QC1-999
Abstract: We discuss the modes B→K(⁎)νν¯ in the context of non-standard neutrino interactions that add incoherently to the SM rates. We consider two scenarios: an additional light neutrino; and neutrino lepton flavour violation. We find that an additional light neutrino that interacts with SM fields via a non-universal Z′ can increase RK(⁎)ν by up to a factor of two without conflicting with Bs−B¯s mixing. This model then predicts rates for Bs→τ+τ− up to six times larger than the SM. In the context of neutrino lepton flavour violation mediated by leptoquarks we find that the current experimental upper bounds on RK(⁎)ν are already more constraining than direct bounds from Bs→τℓ and B→K(⁎)τℓ modes for ℓ=e,μ.
Published: 2021
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8. Charged-lepton-flavor violation in |ΔS| = 1 hyperon decays

Author: Xiao-Gang He, Jusak Tandean, and German Valencia
Subjects: Beyond Standard Model, Effective Field Theories, Kaon Physics, Chiral Lagrangians, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: Abstract Studies of lepton-flavor violation in strangeness-changing (|ΔS| = 1) transitions have a long tradition in the kaon sector where they provide some of the strongest limits on physics beyond the standard model. Recent hints of violation of lepton-flavor universality in B-meson decays have revived interest in lepton-flavor violation as the two phenomena appear simultaneously in many extensions of the standard model. At the same time, the LHCb experiment has produced new results for the hyperon process Σ+ → pμ + μ − and may be in a position to study other rare hyperon decay modes. With this in mind, we investigate |ΔS| = 1 hyperon decays into different-flavor lepton pairs e ± μ ∓ in a model-independent manner and contrast the coverage of parameter space that can be achieved with what is known from kaon modes. We include a comparison with selected two-body leptonic decays of charged mesons, with K → πν v ¯ $$ \overline{v} $$ modes, with μ → e conversion, and with lepton-flavor violating decays of other neutral mesons, all of which constrain the same parameter space in a complementary way.
Published: 2019
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9. Anatomy of a six-parameter fit to the $$b\rightarrow s \ell ^+\ell ^-$$ b→sℓ+ℓ- anomalies

Author: Bernat Capdevila, Ursula Laa, and German Valencia
Subjects: Astrophysics, QB460-466, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: Abstract Discrepancies between measurements of decay modes with an underlying quark level transition $$b\rightarrow s \ell ^+\ell ^-$$ b→sℓ+ℓ- and standard model (SM) predictions have persisted for several years, particularly for the muon channels. The inadequacy of the SM becomes more compelling in a global fit. For example, Capdevila et al. (JHEP 01, 093. arXiv:1704.05340, 2018) described 175 observables by six parameters encoding new physics and quantified the disagreement with the SM at about the $$5\sigma $$ 5σ level. While certain one and two parameter fits have previously been considered in detail, we establish a framework for the detailed discussion of the full 6d fit. We visualize and quantify the 6d $$1\sigma $$ 1σ region around the best fit point and define fit uncertainties for both current and future observables. We then define metrics quantifying the deviations between measurements and both SM and best fit predictions. These metrics relate observables to directions in parameter space, revealing their precise role in the fit, thus providing guidance for future theoretical and experimental work. Some metrics further quantify the role of correlated uncertainties, which turns out to be significant. For example the relevance of angular observables such as $$P_5^\prime $$ P5′ is reduced in this context. Finally, studying the space of observables allows us to discuss the internal tensions in the fit.
Published: 2019
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10. Evolution in schizophrenia diagnosis in the department of Caldas, Colombia. 2010-2015

Author: José Henry Osorio, German Valencia, and Juan Manuel Pérez
Subjects: Mental Health, Epidemiology, Incidence, Prevalence, Schizophrenia, Medicine, Medicine (General), R5-920
Abstract: Introduction: The diagnosis of schizophrenia has experienced a remarkable increase in recent years. Objective: To determine the prevalence and incidence of schizophrenia in the department of Caldas, Colombia, between 2010 and 2015, and to describe its epidemiological profile in this area of the country. Materials and methods: Retrospective and descriptive study. Information on the number of patients treated and the number of consultations in which the diagnosis or reason for consultation was related to schizophrenia diagnostic codes (ICD-10) in Caldas between 2010 and 2015 was analyzed. Data were obtained from the Territorial Health Management Office of Caldas and the Individual Health Service Provision Records of the Colombian Ministry of Health and Social Protection. Annual incidence and prevalence of schizophrenia for the study period were established and the Mann-Whitney U test was used to compare the number of consultations and the number of patients treated according to the type of schizophrenia, with a significance level of p (α)
Published: 2021
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11. Decay rate and asymmetries of Σ+ → pμ + μ −

Author: Xiao-Gang He, Jusak Tandean, and German Valencia
Subjects: Beyond Standard Model, Chiral Lagrangians, Effective Field Theories, Nonperturbative Effects, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: Abstract The LHCb Collaboration has recently reported evidence for the rare hyperon decay Σ+ → pμ + μ − that is consistent with the standard model expectation. Motivated by this new result we revisit the calculation of this mode including both long and short distance contributions. In the standard model this mode is completely dominated by long distance physics and thus subject to large uncertainties. We present a range of predictions for the rate, the dimuon invariant mass spectrum, and a muon polarization asymmetry that covers these uncertainties as well as known constraints. We study the interplay between short and long distance contributions which could result in additional asymmetries, but we find that they are negligible within the standard model. We propose a parameterization of these asymmetries in terms of a couple of constants that can arise from new physics.
Published: 2018
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12. Dynamical projections for the visualization of PDFSense data

Author: Dianne Cook, Ursula Laa, and German Valencia
Subjects: Astrophysics, QB460-466, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: Abstract A recent paper on visualizing the sensitivity of hadronic experiments to nucleon structure (Wang et al. in arXiv:1803.02777, 2018) introduces the tool PDFSense which defines measures to allow the user to judge the sensitivity of PDF fits to a given experiment. The sensitivity is characterized by high-dimensional data residuals that are visualized in a 3-d subspace of the 10 first principal components or using non-linear embeddings. We show how a tour, a dynamic visualisation of high dimensional data, can extend this tool beyond 3-d relationships. This approach enables resolving structure orthogonal to the 2-d viewing plane used so far, and hence finer tuned assessment of the sensitivity.
Published: 2018
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13. Constraints on new physics from $$K \rightarrow \pi \nu {\bar{\nu }}$$ K→πνν¯

Author: Xiao-Gang He, German Valencia, and Keith Wong
Subjects: Astrophysics, QB460-466, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: Abstract We study generic effects of new physics on the rare decay modes $$K_L \rightarrow \pi ^0 \nu {\bar{\nu }}$$ KL→π0νν¯ and $$K^+ \rightarrow \pi ^+ \nu {\bar{\nu }}$$ K+→π+νν¯ . We discuss several cases: left-handed neutrino couplings; right handed neutrino couplings; neutrino lepton flavour violating (LFV) interactions; and $$\Delta I =3/2$$ ΔI=3/2 interactions. The first of these cases has been studied before as it covers many new physics extensions of the standard model; the second one requires the existence of a new light (sterile) right-handed neutrino and its contribution to both branching ratios is always additive to the SM. The case of neutrino LFV couplings introduces a CP conserving contribution to $$K_L \rightarrow \pi ^0 \nu {\bar{\nu }}$$ KL→π0νν¯ which affects the rates in a similar manner as a right handed neutrino as neither one of these interferes with the standard model amplitudes. Finally, we consider new physics with $$\Delta I =3/2$$ ΔI=3/2 interactions to go beyond the Grossman-Nir bound. We find that the rare kaon rates are only sensitive to new physics scales up to a few GeV for this scenario.
Published: 2018
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14. Lepton-flavour-violating gluonic operators: constraints from the LHC and low energy experiments

Author: Yi Cai, Michael A. Schmidt, and German Valencia
Subjects: Beyond Standard Model, Effective Field Theories, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: Abstract Effective operators provide a model-independent description of physics beyond the standard model that is particularly useful given the absence of any signs of new physics at the Large Hadron Collider (LHC). We recast previous LHC analyses to set limits on lepton-flavour-violating gluonic effective operators of dimension 8 and compare our results to existing limits from low-energy precision experiments. Current LHC data constrains the scale Λ of the effective operators to be larger than Λ ≳ 0.5 − 1.6 TeV depending on the flavour and thus provides the most stringent limit for all operators apart from parity-conserving operators of the form GGμ¯PL,Re $$ GG\overline{\mu}{P}_{L,R}e $$, where μ-e conversion in nuclei poses the most stringent constraint.
Published: 2018
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15. Lepton universality violation and right-handed currents in b→cτν

Author: Xiao-Gang He and German Valencia
Subjects: Physics, QC1-999
Abstract: We consider the recent LHCb result for Bc→J/ψτν in conjunction with the existing anomalies in R(D) and R(D⋆) within the framework of a right-handed current with enhanced couplings to the third generation. The model predicts a linear relation between the observables and their SM values in terms of two combinations of parameters. The strong constraints from b→sγ on W−W′ mixing effectively remove one of the combinations of parameters resulting in an approximate proportionality between all three observables and their SM values. To accommodate the current averages for R(D) and R(D⋆), the W′ mass should be near 1 TeV, and possibly accessible to direct searches at the LHC. In this scenario we find that R(J/ψ) is enhanced by about 20% with respect to its SM value and about 1.5σ below the central value of the LHCb measurement. The predicted dΓ/dq2 distribution for B→D(D⋆)τν is in agreement with the measurement and the model satisfies the constraint from the Bc lifetime.
Published: 2018
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16. Erratum to: Constraints on new physics from $$K \rightarrow \pi \nu \bar{\nu }$$ K→πνν¯

Author: Xiao-Gang He, German Valencia, and Keith Wong
Subjects: Astrophysics, QB460-466, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: A missing factor of i in Eq. (C1) has led to an incorrect expression for the last line of Eq. 14. The correct expression should read
Published: 2020
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17. Lepton-flavor-violating semileptonic τ decay and K→πνν¯

Author: Xiao-Gang He, Jusak Tandean, and German Valencia
Subjects: Physics, QC1-999
Abstract: We consider lepton-flavor violation in strangeness changing (|ΔS|=1) semileptonic τ-lepton decays arising from new physics encoded in a standard model effective Lagrangian. Its invariance under the standard model gauge group entails the relevance of other processes which can serve as complementary probes of the new physics operators. We show in particular that for some of them the bounds implied by current data on the rare kaon decays involving a neutrino pair, K→πνν¯, are stronger than the existing limits from direct searches for lepton-flavor-violating semileptonic τ decays. We discuss additional processes affected by the same operators and find that certain leptonic charged-meson decays also provide stricter constraints on a few more of them. Upcoming results of ongoing experiments such as Belle II and NA62 will further test the new physics parameter space.
Published: 2019
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18. CP violation in h→ττ and LFV h→μτ

Author: Alper Hayreter, Xiao-Gang He, and German Valencia
Subjects: Physics, QC1-999
Abstract: The CMS Collaboration has reported a possible lepton flavor violating (LFV) signal h→μτ. Whereas this does not happen in the standard model (SM), we point out that new physics responsible for this type of decay would, in general, also produce charge-parity (CP) violation in h→ττ. We estimate the size of this effect in a model independent manner and find that a large asymmetry, of order 25%, is allowed by current constraints.
Published: 2016
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19. Social, health and consumption profiles and perceptions of treatment in a group recovering alcoholics, Medellín, Colombia

Author: Matilde Álvarez-Gómez and German Valencia-Prieto
Subjects: Public aspects of medicine, RA1-1270, Nursing, RT1-120
Abstract: El alcohol causa anualmente 2.5 millones de muertes, es factor de riesgo para sufrir alguna enfermedad trasmisible, su consumo trae consecuencias negativas en todos los ámbitos. En este estudio descriptivo, el objetivo fue determinar las características sociales, de salud, de consumo y la percepción sobre el tratamiento de rehabilitación en personas alcohólicas. La información se recolecto a través de una encuesta para conocer variables sociales y de salud y una entrevista semiestructurada para determinar la percepción del tratamiento. La mayoría de las personas fueron hombres, de clase media que iniciaron el consumo a los 11 años de edad y cuya comorbilidad psiquiátrica más frecuente fue la depresión. Percibían el tratamiento como un bienestar.
Published: 2015

20. La Participación privada en el sector de agua potable en Antioquia: lecciones que vale la pena tener en cuenta

Author: German Valencia A. and David Tobu00F3n O.
Subjects: Social Sciences, Communities. Classes. Races, HT51-1595
Published: 2005

21. EL JUSTIPRECIO EN LA EXPROPIACION FORZOSA : (DE LA LEY DE EXPROPIACION FORZOSA DE 1954 AL TEXTO REFUNDIDO DE LA LEY DEL SUELO DE 26 DE JUNIO DE 1992).

Author: German Valencia Martín
Subjects: Political science, Political institutions and public administration (General), JF20-2112
Published: 1993
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22. New and Simplified Manual Controls for Projection and Slice Tours, With Application to Exploring Classification Boundaries in High Dimensions.

Author: Ursula Laa, Alex Aumann, Dianne Cook, and German Valencia
Published: 2023
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23. Guía Práctica De Dibujo Para Ingeniería

Author: German Valencia García
Published: 2023

24. Hole or Grain? A Section Pursuit Index for Finding Hidden Structure in Multiple Dimensions.

Author: Ursula Laa, Dianne Cook, Andreas Buja, and German Valencia
Published: 2022
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25. Pursuit of CP violation in hyperon decays at e+e- colliders

Author: Xiao-Gang He, Jusak Tandean, and German Valencia
Subjects: Multidisciplinary
Published: 2022
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26. A slice tour for finding hollowness in high-dimensional data.

Author: Ursula Laa, Dianne Cook, and German Valencia
Published: 2019

27. Lepton-flavour-violating tau decays from triality

Author: Innes Bigaran, Xiao-Gang He, Michael A. Schmidt, German Valencia, and Raymond Volkas
Subjects: High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), FOS: Physical sciences
Abstract: Motivated by flavour symmetry models, we construct theories based on a low-energy limit featuring lepton flavour triality that have the flavour-violating decays $\tau^\pm \to \mu^\pm \mu^\pm e^\mp$ and $\tau^\pm \to e^\pm e^\pm \mu^\mp$ as the main phenomenological signatures of physics beyond the standard model. These decay modes are expected to be probed in the near future with increased sensitivity by the Belle II experiment at the SuperKEKB collider. The simple standard model extensions featured have doubly-charged scalars as the mediators of the above decay processes. The phenomenology of these extensions is studied here in detail., Comment: 24 pages, 4 figures Additional references and neutrino mass discussion added. Matches version accepted for publication in Physical Review D
Published: 2022

28. New and simplified manual controls for projection and slice tours, with application to exploring classification boundaries in high dimensions

Author: Ursula Laa, Alex Aumann, Dianne Cook, and German Valencia
Subjects: FOS: Computer and information sciences, Statistics and Probability, Discrete Mathematics and Combinatorics, Statistics, Probability and Uncertainty, Statistics - Computation, Computation (stat.CO)
Abstract: This paper describes new user controls for examining high-dimensional data using low-dimensional linear projections and slices. A user can interactively change the contribution of a given variable to a low-dimensional projection, which is useful for exploring the sensitivity of structure to particular variables. The user can also interactively shift the center of a slice, for example, to explore how structure changes in local subspaces. The Mathematica package as well as example notebooks are provided, which contain functions enabling the user to experiment with these new manual controls, with one specifically for exploring regions and boundaries produced by classification models. The advantage of Mathematica is its linear algebra capabilities, and interactive cursor location controls. Some limited implementation has also been made available in the R package tourr., 16 pages, 9 figures
Published: 2022

29. Prevalencia de sintomatología depresiva y ansiosa en estudiantes de 14 a 18 años de un colegio privado de Medellín

Author: Ramírez, Carmenza Ricardo, Álvarez, Matilde, Prieto, Germán Valencia, and Otálvaro, Felipe Tirado
Published: 2012
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30. A Slice Tour for Finding Hollowness in High-Dimensional Data

Author: Dianne Cook, German Valencia, and Ursula Laa
Subjects: FOS: Computer and information sciences, Statistics and Probability, Clustering high-dimensional data, Multivariate statistics, Computer science, Computer Science - Human-Computer Interaction, FOS: Physical sciences, Statistics - Computation, 01 natural sciences, Slicing, Human-Computer Interaction (cs.HC), High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), 010104 statistics & probability, Data visualization, Computer graphics (images), 0502 economics and business, Computational statistics, Discrete Mathematics and Combinatorics, 0101 mathematics, Statistical graphics, Computation (stat.CO), 050205 econometrics, business.industry, 05 social sciences, Visualization, Statistics, Probability and Uncertainty, business
Abstract: Taking projections of high-dimensional data is a common analytical and visualisation technique in statistics for working with high-dimensional problems. Sectioning, or slicing, through high dimensions is less common, but can be useful for visualising data with concavities, or non-linear structure. It is associated with conditional distributions in statistics, and also linked brushing between plots in interactive data visualisation. This short technical note describes a simple approach for slicing in the orthogonal space of projections obtained when running a tour, thus presenting the viewer with an interpolated sequence of sliced projections. The method has been implemented in R as an extension to the tourr package, and can be used to explore for concave and non-linear structures in multivariate distributions., 13 pages, 6 figures
Published: 2020
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31. Pandemonium: a clustering tool to partition parameter space—application to the B anomalies

Author: Ursula Laa and German Valencia
Subjects: General Physics and Astronomy
Abstract: We introduce the interactive tool to cluster model predictions that depend on a set of parameters. The model predictions are used to define the coordinates in observable space which go into the clustering. The results of this partitioning are then visualized in both observable and parameter space to study correlations between them. The tool offers multiple choices for coordinates, distance functions and linkage methods within hierarchical clustering. It provides a set of diagnostic statistics and visualization methods to study the clustering results in order to interpret the outcome. The methods are most useful in an interactive environment that enables exploration, and we have implemented them with a graphical user interface in R. We demonstrate the concepts with an application to phenomenological studies in flavor physics in the context of the so-called B anomalies, exploring the tension between $$P_5^\prime $$ P 5 ′ and $$R_K$$ R K and quantifying the resolution in parameter space that can be provided by a given observable set.
Published: 2022
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32. FCNC $B$ and $K$ Meson Decays with Light Bosonic Dark Matter

Author: Xiao-Gang He, Xiao-Dong Ma, and German Valencia
Subjects: High Energy Physics - Phenomenology, Nuclear and High Energy Physics, High Energy Physics - Experiment (hep-ex), High Energy Physics - Phenomenology (hep-ph), FOS: Physical sciences, High Energy Physics - Experiment
Abstract: We consider decays of $B$ and $K$ mesons into a pseudo-scalar or vector meson plus missing energy. Within the SM, these modes originate from flavor changing neutral current (FCNC) processes with two neutrinos in the final state. In this paper we consider the experimental upper bounds on these modes and interpret the difference between these bounds and the SM prediction as a window into new light invisible particles. In particular we consider the case where some new symmetry requires the new particles to be produced in pairs. We first construct the general low energy effective Lagrangian coupling an FCNC with two dark sector particles of spin zero, one-half and one. We then present numerical estimates for the constraints that can be placed on these interactions, finding that an effective new physics scale from ${\cal O}(10)$-${\cal O}(10^{11})$ GeV can be probed, with the exact value strongly depending on the interaction structure as well as the mass of the invisible particle. For $K^+\to \pi^+ \displaystyle{\not} E$ we incorporate into our constraints the effect of using only the signal regions of NA62, and for $B^+\to K^+ \displaystyle{\not} E$ the $q^2$-dependent efficiency of Belle II., Comment: 40 pages, 42 figures, the consideration of Belle II efficiency is clarified and corrected, several new references are added, to appear in JHEP
Published: 2022
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33. Evolución en el diagnóstico de la esquizofrenia en el departamento de Caldas, Colombia. 2010-2015

Author: José Henry Osorio, Juan Manuel Pérez, and German Valencia
Subjects: medicine.medical_specialty, business.industry, Epidemiology, Schizophrenia (object-oriented programming), Incidence, Schizophrenia (MeSH), General Medicine, Esquizofrenia (DeCS), Salud mental, Mental Health, mental disorders, Prevalence, Medicine, Epidemiología, business, Psychiatry, Incidencia, Prevalencia
Abstract: Introduction: The diagnosis of schizophrenia has experienced a remarkable increase in recent years. Objective: To determine the prevalence and incidence of schizophrenia in the department of Caldas, Colombia, between 2010 and 2015, and to describe its epidemiological profile in this area of the country. Materials and methods: Retrospective and descriptive study. Information on the number of patients treated and the number of consultations in which the diagnosis or reason for consultation was related to schizophrenia diagnostic codes (ICD-10) in Caldas between 2010 and 2015 was analyzed. Data were obtained from the Territorial Health Management Office of Caldas and the Individual Health Service Provision Records of the Colombian Ministry of Health and Social Protection. Annual incidence and prevalence of schizophrenia for the study period were established and the Mann-Whitney U test was used to compare the number of consultations and the number of patients treated according to the type of schizophrenia, with a significance level of p (α)
Published: 2021

34. LHC constraints on $$W^\prime ,~Z^\prime $$ <math> <mrow> <msup> <mi>W</mi> <mo>′</mo> </msup> <mo>,</mo> <mspace width='3.33333pt'></mspace> <msup> <mi>Z</mi> <mo>′</mo> </msup> </mrow> </math> that couple mainly to third generation fermions

Author: German Valencia, Alper Hayreter, and Xiao-Gang He
Subjects: Physics, Sterile neutrino, Particle physics, Gauge boson, Annihilation, Large Hadron Collider, Physics and Astronomy (miscellaneous), Star (game theory), High Energy Physics::Phenomenology, FOS: Physical sciences, lcsh:Astrophysics, Fermion, Prime (order theory), High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), lcsh:QB460-466, lcsh:QC770-798, lcsh:Nuclear and particle physics. Atomic energy. Radioactivity, Production (computer science), High Energy Physics::Experiment, Engineering (miscellaneous)
Abstract: We use the results of CMS and ATLAS searches for resonances that decay to $\tau\nu$ or $tb$ and $\tau^+\tau^-$ or $t\bar t$ final states to constrain the parameters of non-universal $W^\prime$ and $Z^\prime$ gauge bosons that couple preferentially to the third generation. For the former we consider production from $c\bar{b}$ annihilation and find very weak constraints on the strength of the interaction and only for the mass range between 800 and 1100 GeV from the $pp \to \tau_h p_T^{\rm miss}$ channel. The constraints on the latter are much stronger and arise from both $t\bar t$ and $\tau^+\tau^-$ production. Treated separately, we find that the weak constraints on the $W^\prime$ still permit an explanation of the $R(D^{(\star)})$ anomalies with a light sterile neutrino whereas the stronger constraints on the $Z^\prime$ exclude significant light sterile neutrino contributions to the $K \to \pi \nu \bar\nu$ rates. Within specific models the masses of $W^\prime$ and $Z^\prime$ are of course related and we briefly discuss the consequences., Comment: 20 pages, 10 figures, matches version accepted for EPJC
Published: 2020

35. CPviolating anomalous couplings inWγandZγproduction at the LHC

Author: Sally Dawson, Sudhir Kumar Gupta, and German Valencia
Published: 2013
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36. Color-Octet Scalar Decays To A Gluon And An Electroweak Gauge Boson In The Manohar-Wise Model

Author: German Valencia and Alper Hayreter
Subjects: Physics, Quark, Gauge boson, Particle physics, 010308 nuclear & particles physics, Branching fraction, Physics beyond the Standard Model, Scalar (mathematics), Electroweak interaction, High Energy Physics::Phenomenology, Yukawa potential, FOS: Physical sciences, 01 natural sciences, Gluon, High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), 0103 physical sciences, High Energy Physics::Experiment, 010306 general physics, Computer Science::Databases
Abstract: We present one loop results for the amplitudes giving rise to couplings between a color octet scalar, a gluon, and an electroweak gauge boson. These amplitudes could signal new physics in $\gamma$ jet, $Z$ jet and $W$ jet production at the LHC. We compute the relevant branching ratios and identify regions of parameter space where these decay modes become important. This can happen for scalar masses below the threshold for decay into heavy quark pairs ($t\bar t$ and $t\bar b$); or for small Yukawa couplings in which case the colored scalars are fermiophobic. In the case of light scalars, ${\cal B}(S\to \gamma g)$ can reach up to 10\% whereas ${\cal B}(S\to Z g)$ can reach a few percent. In the fermiophobic region of parameter space, ${\cal B}(S\to \gamma g)$ and ${\cal B}(S\to Z g)$ can reach up to 72\% and 28\% respectively, whereas ${\cal B}(S\to g g)$ can be 100\%. For the charged scalar, the decay mode ${\cal B}(S^\pm \to W^\pm g)$ can become dominant in both scenarios., Comment: 17 pages, 7 Figures
Published: 2020

37. Additional neutrinos and the B anomalies

Author: German Valencia
Subjects: Physics, Particle physics, Neutrino
Published: 2019
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38. Anatomy of a six-parameter fit to the $$b\rightarrow s \ell ^+\ell ^-$$ <math><mrow><mi>b</mi><mo>→</mo><mi>s</mi><msup><mi>ℓ</mi><mo>+</mo></msup><msup><mi>ℓ</mi><mo>-</mo></msup></mrow></math> anomalies

Author: Ursula Laa, German Valencia, and Bernat Capdevila
Subjects: Quark, Physics, Physics and Astronomy (miscellaneous), 010308 nuclear & particles physics, Physics beyond the Standard Model, Sigma, Observable, Context (language use), lcsh:Astrophysics, Parameter space, Space (mathematics), 01 natural sciences, Standard Model, Theoretical physics, 0103 physical sciences, lcsh:QB460-466, lcsh:QC770-798, lcsh:Nuclear and particle physics. Atomic energy. Radioactivity, 010306 general physics, Engineering (miscellaneous)
Abstract: Discrepancies between measurements of decay modes with an underlying quark level transition $$b\rightarrow s \ell ^+\ell ^-$$ and standard model (SM) predictions have persisted for several years, particularly for the muon channels. The inadequacy of the SM becomes more compelling in a global fit. For example, Capdevila et al. (JHEP 01, 093. arXiv:1704.05340 , 2018) described 175 observables by six parameters encoding new physics and quantified the disagreement with the SM at about the $$5\sigma $$ level. While certain one and two parameter fits have previously been considered in detail, we establish a framework for the detailed discussion of the full 6d fit. We visualize and quantify the 6d $$1\sigma $$ region around the best fit point and define fit uncertainties for both current and future observables. We then define metrics quantifying the deviations between measurements and both SM and best fit predictions. These metrics relate observables to directions in parameter space, revealing their precise role in the fit, thus providing guidance for future theoretical and experimental work. Some metrics further quantify the role of correlated uncertainties, which turns out to be significant. For example the relevance of angular observables such as $$P_5^\prime $$ is reduced in this context. Finally, studying the space of observables allows us to discuss the internal tensions in the fit.
Published: 2019

39. Higgs production constraints on anomalous fermion couplings

Author: German Valencia, Alper Hayreter, Özyeğin University, and Hayreter, Alper
Subjects: Quark, Nuclear and High Energy Physics, Particle physics, High Energy Physics::Lattice, FOS: Physical sciences, Anomalous couplings, 01 natural sciences, dipole moments, High Energy Physics - Phenomenology (hep-ph), 0103 physical sciences, 010306 general physics, Boson, Physics, Anomalous magnetic dipole moment, 010308 nuclear & particles physics, Dipole moments, High Energy Physics::Phenomenology, anomalous couplings, Higgs field, Electric dipole moment, Dipole, High Energy Physics - Phenomenology, Higgs boson, High Energy Physics::Experiment, Lepton, Higgs production
Abstract: Certain anomalous fermion-gauge boson couplings, such as the flavor diagonal anomalous color magnetic (CMDM) and color electric (CEDM) dipole moments of quarks are not fully gauge invariant under the SM. Restoring gauge invariance with an elementary Higgs doublet implies that they also contribute to Higgs boson production at the LHC and we study the corresponding constraints that can be placed on them. In a similar manner we study the constraints that can be placed on the $\tau$-lepton anomalous magnetic moment, electric dipole moment, weak dipole moments, and dimension eight gluonic couplings at the LHC., Comment: 6 pages, 5 figures, ICHEP2014 conference proceeding
Published: 2016
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40. Beyond R(D(*)) with the general type-III 2HDM for b→cτν

Author: German Valencia, R. Martinez, and C. F. Sierra
Subjects: Physics, 010308 nuclear & particles physics, Physics beyond the Standard Model, Star (game theory), Scalar (mathematics), Yukawa potential, Form factor (quantum field theory), Lambda, 01 natural sciences, Pseudoscalar, 0103 physical sciences, CP violation, 010306 general physics, Mathematical physics
Abstract: We review the parameter regions allowed by measurements of $\mathcal{R}(D^{(*)})$ and by a theoretical limit on ${\cal B}(B_{c}\to\tau\nu)$ in terms of generic scalar and pseudoscalar new physics couplings, $g_s$ and $g_p$. We then use these regions as constraints to predict the ranges for additional observables in $b\to c\tau\nu$ including the differential decay distributions $d\Gamma/dq^{2}$; the ratios $\mathcal{R}(J/\psi)$ and $\mathcal{R}(\Lambda_{c})$; and the tau-lepton polarisation in $B\to D^{(\star)}\tau\nu$, with emphasis on the CP violating normal polarisation. Finally we map the allowed regions in $g_s$ and $g_p$ into the parameters of four versions of the Yukawa couplings of the general 2HDM-III model. We find that the model is still viable but could be ruled out by a confirmation of a large $\mathcal{R}(J/\psi)$.
Published: 2018
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41. Review of Particle Physics

Author: J Lesgourgues, Siegfried Bethke, C. Hanhart, P Eerola, Christian W. Bauer, F Takahashi, Oleg Zenin, A. de Gouvea, C. Grojean, O Buchmuller, Masaharu Tanabashi, P. de Jong, J. Erler, R Sekhar Chivukula, M Taševský, S.I. Eidelman, C. W. Walter, D J Miller, A. Piepke, Torbjörn Sjöstrand, Y Sumino, Orin I. Dahl, Herbert K. Dreiner, A Soffer, Chi Lin, Bogdan A. Dobrescu, S. M. Spanier, R E Mitchell, Marcela Carena, Manuella Vincter, Otmar Biebel, M Karliner, V. S. Lugovsky, Ren-Yuan Zhu, J. J. Beatty, C. Patrignani, A Pomarol, U Thoma, Kurtis F Johnson, N Varelas, William J. Marciano, David Milstead, Sw. Banerjee, Michael Doser, P Urquijo, A. Gurtu, A Bettini, Aneesh V. Manohar, L. S. Littenberg, Michael Syphers, Burkert, M C Gonzalez-Garcia, Ron L. Workman, Jamie Holder, German Valencia, Subir Sarkar, M Kenzie, Charles G Wohl, W. Fetscher, J Hisano, W Vogelsang, Th. Gutsche, Zoltan Ligeti, Thibault Damour, K Rabbertz, Marumi Kado, Sharma, G. Cowan, Klaus Mönig, Fabio Maltoni, C. L. Woody, Anatoli Romaniouk, A. Stahl, Michal Kreps, J Ellis, W-M. Yao, B C Allanach, J Anderson, Ken Ichi Hikasa, Eberhard Klempt, Keith A. Olive, V I Belousov, David H. Weinberg, J.J. Hernández-Rey, Meenakshi Narain, Younghoon Kwon, Andreas Ringwald, M O Wascko, K Trabelsi, E. J. Weinberg, R Yoshida, Jonas Rademacker, D. M. Asner, R A Ryutin, Paolo Molaro, C Lourengo, Peter Skands, Vorobyev, Wolfgang Walkowiak, S. B. Lugovsky, B. K. Heltsley, K. S. Lugovsky, Uli Katz, Daniel Tovey, George F. Smoot, Stephen R. Sharpe, S Heinemeyer, Brian D. Fields, H Ramani, Y Gershtein, R S Thorne, Ofer Lahav, K M Black, T Mannel, Timothy Gershon, Yoshinari Hayato, P. Schaffner, E. Blucher, G. Venanzoni, T Skwarnicki, Giancarlo D'Ambrosio, A J Schwartz, D J Robinson, G Rybka, Joey Huston, M S Sozzi, L.J. Rosenberg, L P Lellouch, Sophia L. Stone, U G Meißner, L. R. Wiencke, L Verde, S. Rolli, G. Dissertori, Augusto Ceccucci, S. T. Petcov, Matthias Neubert, Koji Nakamura, J. Beringer, E Pianori, W Zheng, G Zanderighi, Paul William Richardson, Daniel de Florian, Maksym Titov, C Lippmann, K Terashi, Y. Sakai, A Höcker, Ezhela, L. Tiator, Manuel Drees, A Pich, S Profumo, Gavin P. Salam, R. M. Barnett, J Schwiening, E C Aschenauer, Howard Baer, O. Schneider, Tony Gherghetta, P A Zyla, Jack Laiho, T Hyodo, Jonathan L. Rosner, B. Krusche, H J Gerber, Kate Scholberg, Stefan Roesler, Shoji Hashimoto, D Wands, G Aielli, A Holtkamp, Andrei Gritsan, Arnulf Quadt, A Freitas, Alessandro Cerri, U Egede, H. R. Gallagher, G. Gerbier, V A Khoze, S. R. Klein, B. N. Ratcliff, Y Makida, S. P. Wakely, Christoph Grab, Alberto Masoni, M Mikhasenko, Tony Liss, R. N. Cahn, A A Godizov, Paolo Nason, P. Nevski, T. Sumiyoshi, M D'Onofrio, A Lusiani, B. Foster, Thomas DeGrand, N. P. Tkachenko, Martin White, Douglas Scott, M Yokoyama, G P Zeller, M Ryskin, Petr Vogel, Christian Spiering, M A Bychkov, L. Garren, R. Kowalewski, John Terning, Claude Amsler, John Matthews, Y. Nir, A Hebecker, Mario Antonelli, M Ramsey-Musolf, Andreas Vogt, S L Zhu, Andrew R. Liddle, L Baudis, Debadi Chakraborty, Kaustubh Agashe, J Tanaka, S. Sánchez Navas, Howard E. Haber, Frank Krauss, M. C. Goodman, V A Petrov, Martin Grunewald, Fabio Sauli, D A Dwyer, R. G. Van de Water, M. Silari, John A. Peacock, S Willocq, T Shutt, Frank Zimmermann, Filip Moortgat, M Moskovic, Georg G. Raffelt, D. E. Groom, T. Basaglia, The George Washington University (GW), Thomas Jefferson National Accelerator Facility (Jefferson Lab), Florida State University [Tallahassee] (FSU), Helmholtz-Institut für Strahlen- und Kernphysik (HISKP), Rheinische Friedrich-Wilhelms-Universität Bonn, Institut für Kernphysik (IKP), Forschungszentrum Jülich GmbH | Centre de recherche de Juliers, Helmholtz-Gemeinschaft = Helmholtz Association-Helmholtz-Gemeinschaft = Helmholtz Association, University of Maryland [Baltimore], Università degli Studi di Roma Tor Vergata [Roma], University of Cambridge [UK] (CAM), Austrian Academy of Sciences (OeAW), INFN Frascati, Istituto Nazionale di Fisica Nucleare (INFN), Brookhaven National Laboratory [Upton, NY] (BNL), UT-Battelle, LLC-Stony Brook University [SUNY] (SBU), State University of New York (SUNY)-State University of New York (SUNY)-U.S. Department of Energy [Washington] (DOE), University of Oklahoma (OU), University of Louisville, Lawrence Berkeley National Laboratory [Berkeley] (LBNL), Universität Zürich [Zürich] = University of Zurich (UZH), Ohio State University [Columbus] (OSU), National Research Centre Kurchatov Institute, Istituto Nazionale di Fisica Nucleare, Sezione di Padova (INFN, Sezione di Padova), Ludwig-Maximilians-Universität München (LMU), University of Wisconsin Oshkosh (UWO), University of Chicago, Imperial College London, University of Virginia, Fermi National Accelerator Laboratory (Fermilab), CERN [Genève], University of Sussex, University of California (UC), Royal Holloway [University of London] (RHUL), State University of New York (SUNY Canton), Istituto Nazionale di Fisica Nucleare, Sezione di Milano (INFN), Istituto Nazionale di Fisica Nucleare, Sezione di Napoli (INFN, Sezione di Napoli), Institut des Hautes Études Scientifiques (IHES), IHES, Universidad Nacional de San Martin (UNSAM), Northwestern University [Evanston], University of Colorado [Boulder], University of Amsterdam [Amsterdam] (UvA), Yale University [New Haven], University of Liverpool, Universitätsklinikum Bonn (UKB), TKK Helsinki University of Technology (TKK), Monash university, Budker Institute of Nuclear Physics (BINP), Siberian Branch of the Russian Academy of Sciences (SB RAS), University of Illinois [Chicago] (UIC), University of Illinois System, King‘s College London, Departement Physik [ETH Zürich] (D-PHYS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), University of Pittsburgh (PITT), Pennsylvania Commonwealth System of Higher Education (PCSHE), Tufts University [Medford], Rutgers University [Camden], Rutgers University System (Rutgers), University of Minnesota System, Stony Brook University [SUNY] (SBU), State University of New York (SUNY), Argonne National Laboratory [Lemont] (ANL), Departement Erdwissenschaften [ETH Zürich] (D-ERDW), Johns Hopkins University (JHU), Deutsches Elektronen-Synchrotron [Hamburg] (DESY), University College Dublin [Dublin] (UCD), Department of Condensed Matter Physics and Materials Science [TIFR] (CMPMS), Tata Institute for Fundamental Research (TIFR), Universitätsklinikum Tübingen - University Hospital of Tübingen, Eberhard Karls Universität Tübingen = Eberhard Karls University of Tuebingen, Laboratoire Capteurs et Architectures Electroniques (LCAE), Département Métrologie Instrumentation & Information (DM2I), Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Forschungszentrum Jülich GmbH, KEK (High energy accelerator research organization), The University of Tokyo (UTokyo), Heidelberg University, Universidad Autónoma de Madrid (UAM), Universitat de València (UV), Tohoku University [Sendai], University of Delaware [Newark], Michigan State University System, Tokyo Metropolitan University [Tokyo] (TMU), Gran Sasso Science Institute, INFN, Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Tel Aviv University (TAU), Friedrich-Alexander Universität Erlangen-Nürnberg (FAU), University of Warwick [Coventry], Department of Physics [Durham University], Durham University, University of Ljubljana, University of Basel (Unibas), Yonsei University, University College of London [London] (UCL), Syracuse University, Centre de Physique Théorique - UMR 7332 (CPT), Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), CPT - E1 Physique des particules, Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), Rheinisch-Westfälische Technische Hochschule Aachen University (RWTH), Universidade de Lisboa, GSI Helmholtzzentrum für Schwerionenforschung (GSI), City College of New York [CUNY] (CCNY), City University of New York [New York] (CUNY), Scuola Normale Superiore di Pisa (SNS), Université Catholique de Louvain = Catholic University of Louvain (UCL), Universität Siegen [Siegen], Istituto Nazionale di Fisica Nucleare, Sezione di Cagliari (INFN, Sezione di Cagliari), Louisiana State University (LSU), University of Glasgow, Stockholms universitet, Indiana State University, INAF/OATS, Trieste, Italy, Department of Applied Physics, Ghent University, Brown University, Università degli Studi di Milano-Bicocca = University of Milano-Bicocca (UNIMIB), Johannes Gutenberg - Universität Mainz = Johannes Gutenberg University (JGU), Weizmann Institute of Science [Rehovot, Israël], University of Bologna/Università di Bologna, University of Edinburgh, Institute of Molecular Genetics of National Research Centre «Kurchatov Institute» [Moscow, Russia], Russian Academy of Sciences [Moscow] (RAS), Instituto de Fisica Corpuscular (IFIC), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Universitat de València (UV), University of Alabama [Tuscaloosa] (UA), Universitat Autònoma de Barcelona (UAB), Georg-August-University = Georg-August-Universität Göttingen, Karlsruhe Institute of Technology (KIT), University of Bristol [Bristol], Max-Planck-Institut für Physik (Werner-Heisenberg-Institut) (MPI-P), Tsung-Dao Lee Institute, Shanghai Jiao Tong, SLAC National Accelerator Laboratory (SLAC), Stanford University, U.S. Department of Energy [Washington] (DOE), Leopold Franzens Universität Innsbruck - University of Innsbruck, The National Research Nuclear University MEPhI (Moscow Engineering Physics Institute) [Moscow, Russia], University of Mary Washington, Petersburg Nuclear Physics Institute, University of Oxford, Ecole Polytechnique Fédérale de Lausanne (EPFL), Technische Universität München = Technical University of Munich (TUM), University of Cincinnati (UC), University of British Columbia (UBC), University of Washington [Seattle], Istituto Nazionale di Fisica Nucleare [Pisa] (INFN), Lund University [Lund], AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), University of Pisa - Università di Pisa, University of Tennessee System, Northern Illinois University, Nagoya University, Tokyo University of Science [Tokyo], Czech Academy of Sciences [Prague] (CAS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, University of Sheffield [Sheffield], University of Melbourne, Monash University [Melbourne], University of Barcelona, California Institute of Technology (CALTECH), Department of Radiology [Radiologische Universitätsklinik Eberhard-Karls-Universität Tübingen], University of Portsmouth, Columbia University [New York], Colorado School of Mines, University of Massachusetts [Amherst] (UMass Amherst), University of Massachusetts System (UMASS), Max Planck Institute for the Physics of Complex Systems (MPI-PKS), Max-Planck-Gesellschaft, Moscow Institute of Physics and Technology [Moscow] (MIPT), Peking University [Beijing], Institute of High Energy Physics [Beijing] (IHEP), Chinese Academy of Sciences [Changchun Branch] (CAS), Particle Data Group, Institut des Hautes Etudes Scientifiques (IHES), Laboratoire de Physique Théorique et Hautes Energies (LPTHE), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE (UMR_7585)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de l'Accélérateur Linéaire (LAL), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Département de Physique des Particules (ex SPP) (DPP), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), CEA/DSM, Département de Physique des Particules (ex SPP) (DPhP), UCL - SST/IRMP - Institut de recherche en mathématique et physique, Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), ITA, Department of Energy (US), Japan Society for the Promotion of Science, European Commission, Ministry of Education, Culture, Sports, Science and Technology (Japan), Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Science and Technology Facilities Council (STFC), Tanabashi, M, Grp, P, Hagiwara, K, Hikasa, K, Nakamura, K, Sumino, Y, Takahashi, F, Tanaka, J, Agashe, K, Aielli, G, Amsler, C, Antonelli, M, Asner, D, Baer, H, Banerjee, S, Barnett, R, Basaglia, T, Bauer, C, Beatty, J, Belousov, V, Beringer, J, Bethke, S, Bettini, A, Bichsel, H, Biebel, O, Black, K, Blucher, E, Buchmuller, O, Burkert, V, Bychkov, M, Cahn, R, Carena, M, Ceccucci, A, Cerri, A, Chakraborty, D, Chen, M, Chivukula, R, Cowan, G, Dahl, O, D'Ambrosio, G, Damour, T, de Florian, D, de Gouvea, A, Degrand, T, de Jong, P, Dissertori, G, Dobrescu, B, D'Onofrio, M, Doser, M, Drees, M, Dreiner, H, Dwyer, D, Eerola, P, Eidelman, S, Ellis, J, Erler, J, Ezhela, V, Fetscher, W, Fields, B, Firestone, R, Foster, B, Freitas, A, Gallagher, H, Garren, L, Gerber, H, Gerbier, G, Gershon, T, Gershtein, Y, Gherghetta, T, Godizov, A, Goodman, M, Grab, C, Gritsan, A, Grojean, C, Groom, D, Grunewald, M, Gurtu, A, Gutsche, T, Haber, H, Hanhart, C, Hashimoto, S, Hayato, Y, Hayes, K, Hebecker, A, Heinemeyer, S, Heltsley, B, Hernandez-Rey, J, Hisano, J, Hocker, A, Holder, J, Holtkamp, A, Hyodo, T, Irwin, K, Johnson, K, Kado, M, Karliner, M, Katz, U, Klein, S, Klempt, E, Kowalewski, R, Krauss, F, Kreps, M, Krusche, B, Kuyanov, Y, Kwon, Y, Lahav, O, Laiho, J, Lesgourgues, J, Liddle, A, Ligeti, Z, Lin, C, Lippmann, C, Liss, T, Littenberg, L, Lugovsky, K, Lugovsky, S, Lusiani, A, Makida, Y, Maltoni, F, Mannel, T, Manohar, A, Marciano, W, Martin, A, Masoni, A, Matthews, J, Meissner, U, Milstead, D, Mitche, R, Moenig, K, Molaro, P, Moortgat, F, Moskovic, M, Murayama, H, Narain, M, Nason, P, Navas, S, Neubert, M, Nevski, P, Nir, Y, Olive, K, Griso, S, Parsons, J, Patrignani, C, Peacock, J, Pennington, M, Petcov, S, Petrov, V, Pianori, E, Piepke, A, Pomarol, A, Quadt, A, Rademacker, J, Raffelt, G, Ratcliff, B, Richardson, P, Ringwald, A, Roesler, S, Rolli, S, Romaniouk, A, Rosenberg, L, Rosner, J, Rybka, G, Ryutin, R, Sachrajda, C, Sakai, Y, Salam, G, Sarkar, S, Sauli, F, Schneider, O, Scholberg, K, Schwartz, A, Scott, D, Sharma, V, Sharpe, S, Shutt, T, Silari, M, Sjostrand, T, Skands, P, Skwarnicki, T, Smith, J, Smoot, G, Spanier, S, Spieler, H, Spiering, C, Stah, A, Stone, S, Sumiyoshi, T, Syphers, M, Terashi, K, Terning, J, Thoma, U, Thorne, R, Tiator, L, Titov, M, Tkachenko, N, Tornqvist, N, Tovey, D, Valencia, G, Van de Water, R, Varelas, N, Venanzoni, G, Verde, L, Vincter, M, Voge, P, Vogt, A, Wakely, S, Walkowiak, W, Walter, C, Wands, D, Ward, D, Wascko, M, Weiglein, G, Weinberg, D, Weinberg, E, White, M, Wiencke, L, Willocq, S, Woh, C, Womersley, J, Woody, C, Workman, R, Yao, W, Zeller, G, Zenin, O, Zhu, R, Zhu, S, Zimmermann, F, Zyla, P, Anderson, J, Fuller, L, Lugovsky, V, Schaffner, P, Tanabashi, M., Grp, Particle Data, Hagiwara, K., Hikasa, K., Nakamura, K., Sumino, Y., Takahashi, F., Tanaka, J., Agashe, K., Aielli, G., Amsler, C., Antonelli, M., Asner, D. M., Baer, H., Banerjee, Sw., Barnett, R. M., Basaglia, T., Bauer, C. W., Beatty, J. J., Belousov, V. I., Beringer, J., Bethke, S., Bettini, A., Bichsel, H., Biebel, O., Black, K. M., Blucher, E., Buchmuller, O., Burkert, V., Bychkov, M. A., Cahn, R. N., Carena, M., Ceccucci, A., Cerri, A., Chakraborty, D., Chen, M. -C., Chivukula, R. S., Cowan, G., Dahl, O., D'Ambrosio, G., Damour, T., de Florian, D., de Gouvea, A., Degrand, T., de Jong, P., Dissertori, G., Dobrescu, B. A., D'Onofrio, M., Doser, M., Drees, M., Dreiner, H. K., Dwyer, D. A., Eerola, P., Eidelman, S., Ellis, J., Erler, J., Ezhela, V. V., Fetscher, W., Fields, B. D., Firestone, R., Foster, B., Freitas, A., Gallagher, H., Garren, L., Gerber, H. -J., Gerbier, G., Gershon, T., Gershtein, Y., Gherghetta, T., Godizov, A. A., Goodman, M., Grab, C., Gritsan, A. V., Grojean, C., Groom, D. E., Grunewald, M., Gurtu, A., Gutsche, T., Haber, H. E., Hanhart, C., Hashimoto, S., Hayato, Y., Hayes, K. G., Hebecker, A., Heinemeyer, S., Heltsley, B., Hernandez-Rey, J. J., Hisano, J., Hocker, A., Holder, J., Holtkamp, A., Hyodo, T., Irwin, K. D., Johnson, K. F., Kado, M., Karliner, M., Katz, U. F., Klein, S. R., Klempt, E., Kowalewski, R. V., Krauss, F., Kreps, M., Krusche, B., Kuyanov, Yu. V., Kwon, Y., Lahav, O., Laiho, J., Lesgourgues, J., Liddle, A., Ligeti, Z., Lin, C. -J., Lippmann, C., Liss, T. M., Littenberg, L., Lugovsky, K. S., Lugovsky, S. B., Lusiani, A., Makida, Y., Maltoni, F., Mannel, T., Manohar, A. V., Marciano, W. J., Martin, A. D., Masoni, A., Matthews, J., Meissner, U. -G., Milstead, D., Mitche, R. E., Moenig, K., Molaro, P., Moortgat, F., Moskovic, M., Murayama, H., Narain, M., Nason, P., Navas, S., Neubert, M., Nevski, P., Nir, Y., Olive, K. A., Griso, S. Pagan, Parsons, J., Patrignani, C., Peacock, J. A., Pennington, M., Petcov, S. T., Petrov, V. A., Pianori, E., Piepke, A., Pomarol, A., Quadt, A., Rademacker, J., Raffelt, G., Ratcliff, B. N., Richardson, P., Ringwald, A., Roesler, S., Rolli, S., Romaniouk, A., Rosenberg, L. J., Rosner, J. L., Rybka, G., Ryutin, R. A., Sachrajda, C. T., Sakai, Y., Salam, G. P., Sarkar, S., Sauli, F., Schneider, O., Scholberg, K., Schwartz, A. J., Scott, D., Sharma, V., Sharpe, S. R., Shutt, T., Silari, M., Sjostrand, T., Skands, P., Skwarnicki, T., Smith, J. G., Smoot, G. F., Spanier, S., Spieler, H., Spiering, C., Stah, A., Stone, S. L., Sumiyoshi, T., Syphers, M. J., Terashi, K., Terning, J., Thoma, U., Thorne, R. S., Tiator, L., Titov, M., Tkachenko, N. P., Tornqvist, N. A., Tovey, D. R., Valencia, G., Van de Water, R., Varelas, N., Venanzoni, G., Verde, L., Vincter, M. G., Voge, P., Vogt, A., Wakely, S. P., Walkowiak, W., Walter, C. W., Wands, D., Ward, D. R., Wascko, M. O., Weiglein, G., Weinberg, D. H., Weinberg, E. J., White, M., Wiencke, L. R., Willocq, S., Woh, C. C., Womersley, J., Woody, C. L., Workman, R. L., Yao, W. -M., Zeller, G. P., Zenin, O. V., Zhu, R. -Y., Zhu, S. -L., Zimmermann, F., Zyla, P. A., Anderson, J., Fuller, L., Lugovsky, V. S., Schaffner, P., Robinson, D. J., Wohl, C. G., Allanach, B. C., Aschenauer, E. C., Baudis, L., Sekhar Chivukula, R., Egede, U., Gonzalez-Garcia, M. C., Huston, J., Kenzie, M., Khoze, V. A., Lellouch, L. P., Liddle, A. R., Lourenco, C., Mikhasenko, M., Miller, D. J., Mitchell, R. E., Monig, K., Pich, A., Profumo, S., Rabbertz, K., Ramani, H., Ramsey-Musolf, M., Ryskin, M., Schwiening, J., Soffer, A., Sozzi, M. S., Stahl, A., Tasevsky, M., Trabelsi, K., Urquijo, P., van de Water, R., Vogel, P., Vogelsang, W., Vorobyev, V., Yokoyama, M., Yoshida, R., Zanderighi, G., Zheng, W., and Department of Physics
Subjects: high energy, lepton, mixing [neutrino], High Energy Physics::Lattice, Cosmic microwave background, diffraction, Technicolor, Astrophysics, Omega, 01 natural sciences, Physics, Particles & Fields, higgs-boson production, Big Bang nucleosynthesis, cosmological model: parameter space, tau, dark energy, Monte Carlo, fields, pentaquark, instrumentation, Settore FIS/01, gauge boson, Anomalous magnetic dipole moment, deep-inelastic scattering, new physics, Physics, DOUBLE-BETA-DECAY, Electroweak interaction, density [dark matter], HEAVY FLAVOUR, Quarkonium, review, particle, physics, SUPERSYMMETRIC STANDARD MODEL, square-root-s, Physics, Nuclear, grand unified theory, boson: heavy, statistics, Physical Sciences, Higgs boson, axion: mass, flavor: violation, Neutrino, ELECTROWEAK SYMMETRY-BREAKING, numerical calculations: Monte Carlo, on-line, S013EPH, Quark, heavy [boson], [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Physics, Multidisciplinary, anomalous magnetic-moment, electroweak radiative-corrections, dark matter: density, Higgs particle, meson, neutrino masses, neutrino mixing, neutrino oscillations, 114 Physical sciences, CHIRAL PERTURBATION-THEORY, neutrino mixing, Standard Model, quark, 0202 Atomic, Molecular, Nuclear, Particle And Plasma Physics, Nucleosynthesis, quantum chromodynamics, CP: violation, Dark matter, ddc:530, particle physics, Strong Interactions, 010306 general physics, sparticle, S013DF, grand unified theories, PRODUCTION, Gauge boson, Science & Technology, neutrino masses, 010308 nuclear & particles physics, C50 Other topics in experimental particle physics, Particle Data Group, Astronomy and Astrophysics, Deep inelastic scattering, to-leading-order, Automatic Keywords, heavy boson, axion, tables (particle physics), Tetraquark, proton-proton collisions, Supersymmetry, hadron, neutrino: mixing, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], cosmology, Volume (compression), HIGGS-BOSON, UB-VERTICAL-BAR, cosmological model, dark energy density, experimental methods, ddc:539.72021, Physics beyond the Standard Model, standard model, group theory, General Physics and Astronomy, tables, particle physics, high energy physics, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Quantum chromodynamics, energy: high, E Rev 2016, [PHYS.HTHE]Physics [physics]/High Energy Physics - Theory [hep-th], Settore FIS/01 - Fisica Sperimentale, photon, Nuclear & Particles Physics, parameter space [cosmological model], dark energy: density, high [energy], M013WX, fermion-pair production, Nuclear and High Energy Physics, Particle physics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astronomy & Astrophysics, dark matter, statistical analysis, Double beta decay, 0103 physical sciences, conservation law, cold dark-matter, TAU LEPTONS, Astrophysics::Galaxy Astrophysics, tables, DEEP-INELASTIC-SCATTERING, electroweak interaction, High Energy Physics::Phenomenology, 750 GeV diphoton excess, PRODUCTION CROSS-SECTION, baryon, density [dark energy], Physics and Astronomy, gravitation, CKM matrix, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], High Energy Physics::Experiment, supersymmetry, Minimal Supersymmetric Standard Model
Abstract: The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 2,143 new measurements from 709 papers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as supersymmetric particles, heavy bosons, axions, dark photons, etc. Particle properties and search limits are listed in Summary Tables. We give numerous tables, figures, formulae, and reviews of topics such as Higgs Boson Physics, Supersymmetry, Grand Unified Theories, Neutrino Mixing, Dark Energy, Dark Matter, Cosmology, Particle Detectors, Colliders, Probability and Statistics. Among the 120 reviews are many that are new or heavily revised, including a new review on Machine Learning, and one on Spectroscopy of Light Meson Resonances. The Review is divided into two volumes. Volume 1 includes the Summary Tables and 97 review articles. Volume 2 consists of the Particle Listings and contains also 23 reviews that address specific aspects of the data presented in the Listings. The complete Review (both volumes) is published online on the website of the Particle Data Group (pdg.lbl.gov) and in a journal. Volume 1 is available in print as the PDG Book. A Particle Physics Booklet with the Summary Tables and essential tables, figures, and equations from selected review articles is available in print, as a web version optimized for use on phones, and as an Android app., United States Department of Energy (DOE) DE-AC02-05CH11231, government of Japan (Ministry of Education, Culture, Sports, Science and Technology), Istituto Nazionale di Fisica Nucleare (INFN), Physical Society of Japan (JPS), European Laboratory for Particle Physics (CERN), United States Department of Energy (DOE)
Published: 2018
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42. Lepton-flavour-violating gluonic operators: constraints from the LHC and low energy experiments

Author: German Valencia, Yi Cai, and Michael A. Schmidt
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Large Hadron Collider, Current (mathematics), 010308 nuclear & particles physics, Physics beyond the Standard Model, Dimension (graph theory), Flavour, High Energy Physics::Phenomenology, FOS: Physical sciences, Scale (descriptive set theory), Effective Field Theories, 01 natural sciences, High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), 0103 physical sciences, Beyond Standard Model, lcsh:QC770-798, lcsh:Nuclear and particle physics. Atomic energy. Radioactivity, High Energy Physics::Experiment, Limit (mathematics), 010306 general physics, Lepton
Abstract: Effective operators provide a model-independent description of physics beyond the stan- dard model that is particularly useful given the absence of any signs of new physics at the Large Hadron Collider (LHC). We recast previous LHC analyses to set limits on lepton-flavour-violating gluonic effective operators of dimension 8 and compare our results to existing limits from low-energy precision experiments. Current LHC data constrains the scale $\Lambda$ of the effective operators to be larger than $\Lambda\gtrsim 0.5 - 1.6$ TeV depending on the flavour and thus provides the most stringent limit for all operators apart from parity-conserving operators of the form $GG\bar\mu P_{L,R} e$, where $\mu - e$ conversion in nuclei poses the most stringent constraint., Comment: 14 pages, 6 figures; v2: corrected normalization of operators in cross section calculation and matrix elements for tau decays, main conclusions unchanged, accepted by JHEP
Published: 2018
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43. CP violating anomalous couplings in W jet production at the LHC

Author: Hai Tao Li and German Valencia
Subjects: Quantum chromodynamics, Physics, Particle physics, Large Hadron Collider, 010308 nuclear & particles physics, media_common.quotation_subject, Physics beyond the Standard Model, High Energy Physics::Phenomenology, Jet (particle physics), 01 natural sciences, Asymmetry, Nuclear physics, 0103 physical sciences, CP violation, High Energy Physics::Experiment, Production (computer science), B meson, 010306 general physics, media_common
Abstract: T-odd correlations in $Wj$ production at the LHC have been studied recently as a way to measure a phase produced by QCD at NLO by Frederix et al. [T-odd Asymmetry in $\mathrm{W}+\text{jet}$ Events at the LHC, Phys. Rev. Lett. 113, 152001 (2014)]. That study found that the induced asymmetry could be observed with $20\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of 8 TeV data. These T-odd asymmetries can also be induced by $CP$ violating new physics interfering with the SM at LO. In this paper we study this possibility using effective Lagrangians to describe the new physics. We find that the leading contribution arises at dimension eight, and that it necessarily introduces flavor changing neutral currents as well. We discuss the constraints that can be placed on the flavor structure of the new physics operator from studies of FCNC in kaon and B meson decays and then compare the T-odd correlations in $Wj$ induced by $CP$ violating new physics to those induced by QCD at NLO. We quantify the level at which these couplings can be probed at the LHC, and find that they will not affect a measurement of the NLO QCD phases.
Published: 2017
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44. Validity of two Higgs doublet models with a scalar color octet up to a high energy scale

Author: Li Cheng and German Valencia
Subjects: Physics, Particle physics, Octet, Unitarity, 010308 nuclear & particles physics, Scalar (mathematics), High Energy Physics::Phenomenology, FOS: Physical sciences, Scale (descriptive set theory), Parameter space, 01 natural sciences, Two-Higgs-doublet model, High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), 0103 physical sciences, Higgs boson, 010306 general physics, Energy (signal processing)
Abstract: We have recently studied theoretical constraints on the parameters of a 2HDM augmented with a color-octet scalar. In this paper we consider the consequences of requiring the model to remain valid up to very high energy scales, such as the GUT scale. The acceptable region of parameter space is reduced when one insists on vacuum stability, perturbative unitarity and the absence of Landau poles below a given scale. As the scale to which we require the model to be valid is increased, the acceptable region of parameter space for the 2HDM sector is reduced in such a way that it approaches the alignment limit, $\cos(\beta-\alpha)\to 0$, and the masses of $H^0$, $A$ and $H^\pm$ are pushed closer to each other. The parameters of the color octet sector are also restricted to an increasingly smaller region., Comment: 16 pages, 5 figures; referenced added; typos fixed
Published: 2017

45. Probing new physics with τ-leptons at the LHC

Author: German Valencia
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Large Hadron Collider, Physics beyond the Standard Model, media_common.quotation_subject, High Energy Physics::Phenomenology, FOS: Physical sciences, Drell–Yan process, Asymmetry, Resonance (particle physics), Atomic and Molecular Physics, and Optics, High Energy Physics - Experiment, Gluon, High Energy Physics - Phenomenology, High Energy Physics - Experiment (hep-ex), High Energy Physics - Phenomenology (hep-ph), High Energy Physics::Experiment, Leptoquark, Nuclear Experiment, media_common, Lepton
Abstract: We discuss new physics that can show up in the $\tau^+\tau^-$ production process at the LHC but not in the dimuon or the dielectron channels. We consider three different generic possibilities: a new resonance in the Drell-Yan process in the form of a non-universal $Z^\prime$; a new non-resonant contribution to $q\bar{q}\to \tau^+\tau^-$ in the form of leptoquarks; and contributions from gluon fusion due to effective lepton gluonic couplings. We emphasize the use of the charge asymmetry both to discover new physics and to distinguish between different possibilities, Comment: Prepared for TAU2012
Published: 2014
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46. Flavor changing neutral currents and a Z′

Author: German Valencia
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Top quark, Coupling strength, Cabibbo–Kobayashi–Maskawa matrix, High Energy Physics::Lattice, Physics beyond the Standard Model, High Energy Physics::Phenomenology, Fermion, Condensed Matter Physics, Atomic and Molecular Physics, and Optics, Third generation, High Energy Physics::Experiment, Physical and Theoretical Chemistry, Flavor, Ansatz
Abstract: We consider a non-universal Z′ that affects primarily the third generation fermions as an example of new physics associated with the top-quark. We first discuss constraints on the mass and coupling strength of such a Z′. We then turn our attention to the flavor changing neutral currents (FCNC) present in the model. We discuss the experimental constraints and their implications. We propose an ansatz to understand the smallness of the FCNC in terms of the CKM matrix.
Published: 2013
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47. Two Higgs doublet models augmented by a scalar colour octet

Author: Li Cheng and German Valencia
Subjects: Physics, Particle physics, Nuclear and High Energy Physics, Photon, Large Hadron Collider, Octet, 010308 nuclear & particles physics, Physics beyond the Standard Model, High Energy Physics::Lattice, Scalar (mathematics), High Energy Physics::Phenomenology, FOS: Physical sciences, 01 natural sciences, Gluon, High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), 0103 physical sciences, Higgs boson, High Energy Physics::Experiment, 010306 general physics
Abstract: The LHC is now studying in detail the couplings of the Higgs boson in order to determine if there is new physics. Many recent studies have examined the available fits to Higgs couplings from the perspective of constraining two Higgs doublet models (2HDM). In this paper we extend those studies to include constraints on the one loop couplings of the Higgs to gluons and photons. These couplings are particularly sensitive to the existence of new colored particles that are hard to detect otherwise and we use them to constrain a 2HDM augmented with a color-octet scalar, a possibility motivated by minimal flavor violation. We first study theoretical constraints on this model and then compare them with LHC measurements., 23 pages, 10 figures; Matched the publication version
Published: 2016

48. Z′model forb→sℓℓ¯flavor anomalies

Author: German Valencia, Cheng-Wei Chiang, and Xiao-Gang He
Subjects: Physics, Particle physics, 010308 nuclear & particles physics, Physics beyond the Standard Model, Electroweak interaction, Observable, Fermion, 01 natural sciences, Third generation, Nuclear physics, 0103 physical sciences, 010306 general physics, Flavor, Boson, Gauge symmetry
Abstract: We study the implications of flavor-changing neutral currents (FCNC’s) in a model with the SU(2)l×SU(2)h×U(1)Y electroweak gauge symmetry for several anomalies appearing in b→sll¯ induced B decays in LHCb data. In this model, SU(2)l and SU(2)h govern the left-handed fermions in the first two generations and the third generation, respectively. The physical Z and Z′ generate the b→s transition at tree level, leading to additional contributions to the b→s semileptonic operators O9,10. We find that although Bs-B¯s mixing constrains the parameters severely, the model can produce values of C9,10NP in the range determined by Descotes-Genon et al. (Global analysis of b→sll anomalies, arXiv:1510.04239) for this scenario to improve the global fit of observables in decays induced by the b→sμμ¯ transition. The Z′ boson in this model also generates tree-level FCNC’s for the leptonic interactions that can accommodate the experimental central value of RK=B(B→Kμμ¯)/B(B→Kee¯)=0.75. In this case, the model predicts sizable branching ratios for B→Keτ¯, B→Kτe¯, and an enhancement of B→Kττ¯ with respect to its standard model value.
Published: 2016
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49. Ansatz for small FCNC with a non-universal Z′

Author: Xiao-Gang He and German Valencia
Subjects: Quark, Physics, Nuclear and High Energy Physics, Particle physics, Meson, High Energy Physics::Lattice, High Energy Physics::Phenomenology, High Energy Physics::Experiment, Mass matrix, Mixing (physics), Ansatz
Abstract: It is well known that a non-universal Z ′ induces tree-level FCNC which are severely constrained by experiment, most notably meson mixing. We point out that there is a class of models, with a down-quark mass matrix of the Georgi–Jarlskog form, in which the FCNC in the down-type quark sector vanish or are strongly suppressed. The largest FCNC in these models would occur in the tc transition with a strength comparable to V t s .
Published: 2009
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50. T-odd correlations from the top-quark chromoelectric dipole moment in lepton plus jets top-pair events

Author: Alper Hayreter, German Valencia, Özyeğin University, and Hayreter, Alper
Subjects: Physics, Particle physics, Top quark, 010308 nuclear & particles physics, Physics beyond the Standard Model, High Energy Physics::Phenomenology, Parton, Context (language use), 01 natural sciences, Standard Model, Nuclear physics, Pair production, 0103 physical sciences, CP violation, High Energy Physics::Experiment, 010306 general physics, Lepton
Abstract: Due to copyright restrictions, the access to the full text of this article is only available via subscription. There exist several recent studies of the top-quark chromoelectric dipole moment (CEDM) in the context of searching for charge parity violating signals in top-quark pair production at the LHC. Most of these studies constrain the CEDM either from deviations in the top-pair cross section from its standard model value, or from T-odd asymmetries in the dimuon channel. Motivated by ATLAS and CMS interest, we extend the study of T-odd asymmetries to the lepton plus jets channel. At the parton level, using madgraph5, we identify the most promising signals and their statistical sensitivity. We find that the signals with larger sensitivity to the CEDM require distinguishing between b and b¯ jets and propose a simple way to address this. DOE ; ARC Centre of Excellence for Particle Physics at the Terascale
Published: 2016

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