1,006 results on '"Luna, E."'
Search Results
2. Odderon contribution in light of the LHC low-$t$ data
- Author
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Luna, E. G. S., Ryskin, M. G., and Khoze, V. A.
- Subjects
High Energy Physics - Phenomenology ,High Energy Physics - Experiment - Abstract
We perform the analysis of elastic scattering $pp$ and $\bar{p}p$ data at low momentum transfer $|t|<0.1$ GeV$^2$ within large collider energy interval $\sqrt{s}=50$ GeV - 13 TeV in order to evaluate quantitatively the possible Odderon contribution. We use the two-channel eikonal model, which naturally accounts for the screening of the Odderon amplitude by $C$-even (Pomeron) exchanges., Comment: 17 pages, 8 figures; v2 minor changes, typo corrected, a footnote added, version to be published in Phys. Rev. D
- Published
- 2024
3. Unitarity effects in elastic scattering at the LHC
- Author
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Maneyro, M., Luna, E. G. S., and Peláez, M.
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High Energy Physics - Phenomenology ,High Energy Physics - Experiment ,High Energy Physics - Theory - Abstract
We study the high-energy behavior of the elastic scattering amplitude using two distinct unitarization schemes: the eikonal and the $U$-matrix. Our analysis begins with a formalism involving solely Pomerons, incorporating pion-loop insertions in the Pomeron trajectory representing the nearest singularity generated by $t$-channel unitarity. Subsequently, we explore a scenario that includes the presence of an Odderon. In our analyses, we explore the tension between the TOTEM and the ATLAS measurements for $\sigma_{tot}$ and $d\sigma/dt$ at 7, 8, and 13 TeV, and the subsequent implications for the properties of both the Pomeron and Odderon. Our results show that the Odderon phase factor $\xi_{\Bbb O}= -1$ is favored in both unitarization schemes. More interestingly, this specific phase factor stands as the sole one that aligns with results consistent with a non-zero Odderon coupling., Comment: 15 pages, 2 figures, 4 tables
- Published
- 2024
4. Effect of the growth temperature and the AlN mole fraction on In incorporation and properties of quaternary III-nitride layers grown by molecular beam epitaxy
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Fernández-Garrido, S., Redondo-Cubero, A., Gago, R., Bertram, F., Christen, J., Luna, E., Trampert, A., Pereiro, J., Muñoz, E., and Calleja, E.
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Condensed Matter - Materials Science - Abstract
Indium incorporation into wurtzite (0001)-oriented In$_{x}$Al$_{y}$Ga$_{1-x-y}$N layers grown by plasma-assisted molecular beam epitaxy was studied as a function of the growth temperature (565-635 $^{\circ}$C) and the AlN mole fraction (0.01 < y < 0.27). The layer stoichiometry was determined by Rutherford backscattering spectrometry (RBS). RBS shows that Indium incorporation decreased continuously with increasing growth temperature due to thermally enhanced dissociation of In-N bonds and for increasing AlN mole fractions. High resolution x-ray diffraction and transmission electron microscopy (TEM) measurements did not show evidence of phase separation. The mosaicity of the quaternary layers was found to be mainly determined by the growth temperature and independent on alloy composition within the range studied. However, depending on the AlN mole fraction, nanometer-sized composition fluctuations were detected by TEM. Photoluminescence spectra showed a single broad emission at room temperature, with energy and bandwidth S- and W-shaped temperature dependences typical of exciton localization by alloy inhomogeneities. Cathodo-luminescence measurements demonstrated that the alloy inhomogeneities, responsible of exciton localization, occur on a lateral length scale below 150 nm, which is corroborated by TEM.
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- 2024
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5. Optical characterization of GaAs-based Schottky photovoltaic heterostructures with embedded III-N-V quantum wells
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Pérez-Oviedo, T. A., Bustos-Ibarra, M. I., Vera-Gallegos, P. A., Belio-Manzano, A., Olvera-Enríquez, J. P., Briones, E., Lopez-Luna, E., Méndez-García, V. H., Espinosa-Vega, L. I., and Cortes-Mestizo, I. E.
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- 2024
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6. Nonperturbative gluon exchange in $pp$ elastic scattering at TeV energies
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Bopsin, G. B., Luna, E. G. S., Natale, A. A., and Peláez, M.
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High Energy Physics - Phenomenology ,High Energy Physics - Theory - Abstract
We investigate the two-gluon-exchange model of the Pomeron using nonperturbative gluon propagators characterized by a dynamical mass scale. We present the results for an analysis of the available $pp$ differential cross section data at TeV energies which accounts for dynamical gluon masses obtained from a non-linear version of the Schwinger-Dyson equations. We show that our two-gluon exchange model gives a very good description of the LHC data, provided we demand the Reggeization of the scattering amplitude and make a suitable choice for the convolution of proton wave functions., Comment: 9 pages, 6 figures, 2 tables, text improved, references added. Version to be published in Phys. Rev. D
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- 2022
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7. #VacinaMare campaign: addressing vaccine inequity in socially vulnerabilised communities
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Amanda A. Batista-da-Silva, Leonardo S.L. Bastos, Luna E. Arouca, Thiago W. Gonzaga-da-Silva, Silvio Hamacher, Fernando A. Bozza, and Otavio T. Ranzani
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Public aspects of medicine ,RA1-1270 - Published
- 2024
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8. Performance-based limit criteria and temperature mitigation alternatives for the holistic reassessment of a mass concrete structure
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Luna E. Al-Hasani, Jisoo Park, Jason B. Brown, Oscar Antommattei, Yong K. Cho, T. Russell Gentry, and Kimberly E. Kurtis
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Mass concrete ,Isothermal calorimetry ,Performance-based limits ,Mitigated mix designs ,Thermal cracking ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
The durability of mass concrete structures may be compromised due to stresses and cracking induced by temperature rise due to cement hydration and concrete’s insulating capacity. Delayed ettringite formation and thermal cracking may occur when maximum temperatures and maximum temperature differences are greater than the allowable limits. Through a real-world case study in Douglasville, Georgia, this work investigates how modeling, construction decisions, and thermal limits influence the construction decisions of a mass concrete footing and abutment wall. Thermal control measures deemed necessary to satisfy thermal limit criteria for the abutment wall construction included precooling the concrete using liquid nitrogen and post-cooling the abutment wall using internal cooling pipes. Both measures, however, increased the cost and complexity of construction. The footing also required pre-cooling of the concrete even though it was not classified as mass concrete. In this work, the temperature development of the footing and the wall is modeled through a progressive approach based on laboratory-scale isothermal calorimetry. Based on the modeling, alternative design and construction options to satisfy thermal limits imposed by several Department of Transportation (DOT) guidelines, but at lower cost and complexity, are considered. A performance-based temperature difference limit (PBTDL) that considers a certain project’s mechanical performance and material properties is introduced as an alternative to the current difference limit prescribed by DOTs, which in certain cases can be inflexible, overly conservative, and overly simplified. The analysis also investigates the geometric hard limit specified by certain DOTs to classify mass concrete. The investigation shows that the cost and complexity of mass concrete construction can be significantly reduced with progressive modeling, performance-based decision-making, and a holistic outlook on the mass concrete problem.
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- 2024
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9. Prevalence, risk factors, and impact of long COVID in a socially vulnerable community in Brazil: a prospective cohort study
- Author
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Azambuja, Pedro, Bastos, Leonardo S.L., Batista-da-Silva, Amanda A., Ramos, Grazielle Viana, Kurtz, Pedro, Dias, Carolina M.C., da Silva, Everton P., Arouca, Luna E., Soares, Jesus, Sejvar, James J., Sigfrid, Louise, Ranzani, Otavio T., Hamacher, Silvio, and Bozza, Fernando A.
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- 2024
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10. Performance-based limit criteria and temperature mitigation alternatives for the holistic reassessment of a mass concrete structure
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Al-Hasani, Luna E., Park, Jisoo, Brown, Jason B., Antommattei, Oscar, Cho, Yong K., Gentry, T. Russell, and Kurtis, Kimberly E.
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- 2024
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11. New plasma regimes with small ELMs and high confinement at the Joint European Torus
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Garcia, J., de la Luna, E., Sertoli, M., Casson, F., Mazzi, S., Stancar, Z., Szepesi, G., Frigione, D., Garzotti, L., Rimini, F., van Eester, D., Lomas, P., Sozzi, C., Aiba, R. N., Coelho, R., Frasinetti, L., Huijsmans, G., and Liu, F.
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Physics - Plasma Physics ,Nuclear Experiment - Abstract
New plasma regimes with high confinement, low core impurity accumulation and small Edge localized mode (ELMs) perturbations have been obtained close to ITER conditions in magnetically confined plasmas from the Joint European torus (JET) tokamak. Such regimes are achieved by means of optimized particle fuelling conditions which trigger a self-organize state with a strong increase in rotation and ion temperature and a decrease of the edge density. An interplay between core and edge plasma regions leads to reduced turbulence levels and outward impurity convection. These results pave the way to an attractive alternative to the standard plasmas considered for fusion energy generation in a tokamak with metallic wall environment such as the ones expected in ITER
- Published
- 2021
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12. Matter-antimatter asymmetry and non-inertial effects
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Silveira, V. M. G., Vasconcellos, C. A. Z., Luna, E. G. S., and Hadjimichef, D.
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General Relativity and Quantum Cosmology ,High Energy Physics - Phenomenology - Abstract
We investigate non-inertial effects on $CP$-violating processes using a model, based on the framework of quantum field theory in curved spacetimes, devised to account for the decay of accelerated particles. We show that the $CP$ violation parameter for the decay of accelerated kaons into two pions decreases very slightly as very high accelerations are achieved, implying decreased asymmetry between matter and antimatter in this regime. We discuss the relationship between these results and cosmological processes surrounding matter-antimatter asymmetry and argue that, due to the connection between non-inertial and thermal phenomena established by the Unruh effect, this kind of computation may prove useful in furthering the understanding of thermodynamical effects in curved spacetimes., Comment: 15 pages, 1 table, 4 figures
- Published
- 2020
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13. Soft Pomeron in light of the LHC correlated data
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Broilo, M., Fagundes, D. A., Luna, E. G. S., and Peláez, M.
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High Energy Physics - Phenomenology ,High Energy Physics - Experiment ,High Energy Physics - Theory - Abstract
The LHC has released precise measurements of elastic proton-proton scattering that provide a unique constraint on the asymptotic behavior of the scattering amplitude at high energies. Recent reanalyses of part of these data indicate that the central values of some forward quantities would be different than initially observed. We introduce correlation information between the original and the reanalyzed data sets in a way suitable for a global fitting analysis of all data. The careful treatment of correlated errors leads to much less stringent limits on the $\rho$ uncertainty and sets up the stage for describing the forward data using a scattering amplitude dominated by only crossing-even terms. In the light of these correlated data we determine the parameters of the soft Pomeron from the Regge theory. We use Born-level and eikonalized amplitudes. In the Born-level case we estimate the contribution of the double Pomeron exchange, while in the latter case we investigate the role of the eikonalization in both the one- and two-channel models. The role of the proton-Pomeron vertex form and of the nearest $t$-channel singularity in the Pomeron trajectory receives particular attention. We discuss the implications of our results and present predictions for the total cross section and the $\rho$ parameter in proton-proton collisions at LHC and cosmic ray energies., Comment: 17 pages, 6 figures, 5 tables, minor typos fixed. Version to be published in Phys. Rev. D. arXiv admin note: text overlap with arXiv:1908.01040
- Published
- 2020
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14. Non-inertial effects on CP-violating systems
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Silveira, V. M. G., Vasconcellos, C. A. Z., Luna, E. G. S., and Hadjimichef, D.
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High Energy Physics - Phenomenology ,High Energy Physics - Theory - Abstract
An analysis of accelerated kaon decays based on the Unruh effect shows a slight decrease in a CP-violation parameter for very high accelerations, as a consequence of the previously know increase in decay rates for non-inertial systems. Its consequences on the understanding of the relation between thermal and non-inertial phenomena are briefly discussed., Comment: 4 pages, 1 table, 2 figures, to be published in Astronomische Nachrichten. Contribution to the Proceedings of the 9th International Workshop on Astronomy and Relativistic Astrophysics, Mexico City, Mexico, 6-12 September, 2020
- Published
- 2020
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15. QCD effective charges and the structure function $F_{2}$ at small-$x$: Higher twist effects
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Hadjimichef, D., Luna, E. G. S., and Peláez, M.
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High Energy Physics - Phenomenology ,High Energy Physics - Experiment ,High Energy Physics - Lattice ,High Energy Physics - Theory - Abstract
We consider the effect of higher twist operators of the Wilson operator product expansion in the structure function $F_{2}(x,Q^{2})$ at small-$x$, taking into account QCD effective charges whose infrared behavior is constrained by a dynamical mass scale. The higher twist corrections are obtained from the renormalon formalism. Our analysis is performed within the conventional framework of next-to-leading order, with the factorization and renormalization scales chosen to be $Q^{2}$. The infrared properties of QCD are treated in the context of the generalized double-asymptotic-scaling approximation. We show that the corrections to $F_{2}$ associated with twist-four and twist-six are both necessary and sufficient for a good description of the deep infrared experimental data., Comment: 19 pages, 6 figures, text improved, references added, gluon distribution function calculated. To be published in Phys. Lett. B
- Published
- 2019
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16. Forward elastic scattering: Dynamical gluon mass and semihard interactions
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Broilo, M., Fagundes, D. A., Luna, E. G. S., and Menon, M. J.
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High Energy Physics - Phenomenology ,High Energy Physics - Experiment - Abstract
The role of low-$x$ parton dynamics in dictating the high-energy behavior of forward scattering observables at LHC energies is investigated using a QCD-based model with even-under-crossing amplitude dominance at high-energies. We explore the effects of different sets of pre- and post-LHC fine-tuned parton distributions on the forward quantities $\sigma_{tot}$ and $\rho$, from $pp$ and $\bar{p}p$ scattering in the interval 10 GeV - 13 TeV. We also investigate the role of the leading soft contribution, the low-energy cuttoff, and the energy dependence of the semihard form factor on these observables. We show that in all cases investigated the highly restrictive data on $\rho$ parameter at $\sqrt{s}=13$ TeV indicate that a crossing-odd component may play a crucial role in forward elastic scattering at the highest energies. In the Regge language an odd-under-crossing object is called Odderon., Comment: 15 pages, 9 tables, 9 figures. One table and two references added, minor revision and discussions improved
- Published
- 2019
17. Proton-proton forward scattering at the LHC
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Broilo, M., Fagundes, D. A., Luna, E. G. S., and Menon, M. J.
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High Energy Physics - Phenomenology ,High Energy Physics - Experiment ,Nuclear Theory - Abstract
Recently the TOTEM experiment at the LHC has released measurements at $\sqrt{s} = 13$ TeV of the proton-proton total cross section, $\sigma_{tot}$, and the ratio of the real to imaginary parts of the forward elastic amplitude, $\rho$. Since then an intense debate on the $C$-parity asymptotic nature of the scattering amplitude was initiated. We examine the proton-proton and the antiproton-proton forward data above 10 GeV in the context of an eikonal QCD-based model, where nonperturbative effects are readily included via a QCD effective charge. We show that, despite an overall satisfactory description of the forward data is obtained by a model in which the scattering amplitude is dominated by only crossing-even elastic terms, there is evidence that the introduction of a crossing-odd term may improve the agreement with the measurements of $\rho$ at $\sqrt{s} = 13$ TeV. In the Regge language the dominant even(odd)-under-crossing object is the so called Pomeron (Odderon)., Comment: 5 pages, 2 figures, 1 table. Phenomenological approach revised, results and conclusions changed, suggesting now the presence of Odderon effects in forward scattering (once confirmed the TOTEM data at 13 TeV)
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- 2019
- Full Text
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18. Forward Elastic Scattering and Pomeron Models
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Broilo, M., Luna, E. G. S., and Menon, M. J.
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High Energy Physics - Phenomenology ,High Energy Physics - Experiment ,Nuclear Theory - Abstract
Recent data from LHC13 by the TOTEM Collaboration have indicated an unexpected decrease in the value of the $\rho$ parameter and a $\sigma_{tot}$ value in agreement with the trend of previous measurements at 7 and 8 TeV. These data at 13 TeV are not simultaneously described by the predictions from Pomeron models selected by the COMPETE Collaboration, but show agreement with the maximal Odderon dominance, as recently demonstrated by Martynov and Nicolescu. Here we present a detailed analysis on the applicability of Pomeron dominance by means of a general class of forward scattering amplitude, consisting of even-under-crossing leading contributions associated with single, double and triple poles in the complex angular momentum plane. We carry out fits to $pp$ and $\bar{p}p$ data in the interval 5 GeV - 13 TeV. The data set comprises all the accelerator data below 7 TeV and we consider two independent ensembles by adding either only the TOTEM data or TOTEM and ATLAS data at the LHC energy region. In the data reductions to each ensemble the uncertainty regions are evaluated with both one and two standard deviation ($\sim$ 68 \% and $\sim$ 95 \% CL, respectively). Besides the general analytic model, we investigate four particular cases of interest, three of them typical of outstanding models in the literature. We conclude that, within the experimental and theoretical uncertainties and both ensembles, the general model and three particular cases are not able to describe the $\sigma_{tot}$ and $\rho$ data at 13 TeV simultaneously. However, if the discrepancies between the TOTEM and ATLAS data are not resolved, one Pomeron model, associated with double and triple poles and with only 7 free parameters, seems not to be excluded by the complete set of experimental information presently available., Comment: 27 pages, 10 figures, 5 tables, minor corrections and one paragraph added in the Introduction; Accepted for publication in Phys. Rev. D
- Published
- 2018
- Full Text
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19. Exclusive production of pions and the pion distribution amplitude
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Fagundes, D. A., Luna, E. G. S., Natale, A. A., and Pelaez, M.
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High Energy Physics - Phenomenology ,High Energy Physics - Experiment ,Nuclear Theory - Abstract
Considering, as a limit case, an approximately flat pion distribution amplitude, which is determined from the hardest, in momentum space, solution of the Bethe-Salpeter equation for the pion wave function, we compute the pion transition form factor $F_{\pi\gamma\gamma^{*}}(Q^{2})$ and the pion form factor $F_{\pi}(Q^2)$, taking into account the LO as well as NLO form of the hard coefficient function entering the leading-twist factorization formula. We also compute the exclusive photoproduction of pions pairs at high energies, $\gamma \gamma \to \pi^{+}\pi^{-}$, where perturbative QCD can be used to compute the hard scattering matrix elements. We verify that the existent data for exclusive pion production can be reasonably described as a function of such flat distribution amplitude., Comment: 9 pages, 5 figures, extended discussion, new references, version to appear in J. Phys. G
- Published
- 2018
20. Soft Pomerons and the Forward LHC Data
- Author
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Broilo, M., Luna, E. G. S., and Menon, M. J.
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High Energy Physics - Phenomenology ,High Energy Physics - Experiment - Abstract
Recent data from LHC13 by the TOTEM Collaboration on $\sigma_{tot}$ and $\rho$ have indicated disagreement with all the Pomeron model predictions by the COMPETE Collaboration (2002). On the other hand, as recently demonstrated by Martynov and Nicolescu (MN), the new $\sigma_{tot}$ datum and the unexpected decrease in the $\rho$ value are well described by the maximal Odderon dominance at the highest energies. Here, we discuss the applicability of Pomeron dominance through fits to the \textit{most complete set} of forward data from $pp$ and $\bar{p}p$ scattering. We consider an analytic parametrization for $\sigma_{tot}(s)$ consisting of non-degenerated Regge trajectories for even and odd amplitudes (as in the MN analysis) and two Pomeron components associated with double and triple poles in the complex angular momentum plane. The $\rho$ parameter is analytically determined by means of dispersion relations. We carry out fits to $pp$ and $\bar{p}p$ data on $\sigma_{tot}$ and $\rho$ in the interval 5 GeV - 13 TeV (as in the MN analysis). Two novel aspects of our analysis are: (1) the dataset comprises all the accelerator data below 7 TeV and we consider \textit{three independent ensembles} by adding: either only the TOTEM data (as in the MN analysis), or only the ATLAS data, or both sets; (2) in the data reductions to each ensemble, uncertainty regions are evaluated through error propagation from the fit parameters, with 90 \% CL. We argument that, within the uncertainties, this analytic model corresponding to soft Pomeron dominance, does not seem to be excluded by the \textit{complete} set of experimental data presently available., Comment: 10 pages, 4 figures, 1 table. Two paragraphs and four references added. Accepted for publication in Phys. Lett. B
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- 2018
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21. Leading Pomeron Contributions and the TOTEM Data at 13 TeV
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Broilo, M., Luna, E. G. S., and Menon, M. J.
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High Energy Physics - Phenomenology ,High Energy Physics - Experiment - Abstract
The recent data by the TOTEM Collaboration on $\sigma_{tot}$ and $\rho$ at 13 TeV, have shown agreement with a leading Odderon contribution at the highest energies, as demonstrated in the very recent analysis by Martynov and Nicolescu (MN). In order to investigate the same dataset by means of Pomeron dominance, we introduce a general class of forward scattering amplitude, with leading contributions even under crossing, associated with simple, double and triple poles in the complex angular momentum plane. For the lower energy region, we consider the usual non-degenerated Regge trajectories, with even and odd symmetry. The analytic connection between $\sigma_{tot}$ and $\rho$ is obtained by means of dispersion relations and we carry out fits to $pp$ and $\bar{p}p$ data in the interval $\sqrt{s}=5$ GeV - 13 TeV; following MN we consider only the TOTEM data at the LHC energy region. From the fits, we conclude that the general analytic model, as well as some particular cases representing standard parameterizations, are not able to describe satisfactorily the $\sigma_{tot}$ and $\rho$ data at 13 TeV. Further analyses in course and some perspectives are outlined., Comment: 4 pages, 1 table, 1 figure, misprints corrected, minor changes in the text, four references added, one sentence and one reference updated. Poster presented at the XIV International Workshop on Hadron Physics, Florian\'opolis, Brazil, March 2018
- Published
- 2018
22. The role of vagus nerve stimulation in the treatment of refractory epilepsy: clinical outcomes and impact on quality of life
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Martorell-Llobregat, C., González-López, P., Luna, E., Asensio-Asensio, M., Jadraque-Rodríguez, R., García-March, G., and Moreno-López, P.
- Published
- 2022
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23. Papel de la estimulación del nervio vago en el tratamiento de la epilepsia refractaria. Resultados clínicos e impacto en la calidad de vida
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Martorell-Llobregat, C., González-López, P., Luna, E., Asensio-Asensio, M., Jadraque-Rodríguez, R., García-March, G., and Moreno-López, P.
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- 2022
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24. Quantitative systems pharmacology modeling sheds light into the dose response relationship of a trispecific T cell engager in multiple myeloma
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Abrams, R. E., Pierre, K., El-Murr, N., Seung, E., Wu, L., Luna, E., Mehta, R., Li, J., Larabi, K., Ahmed, M., Pelekanou, V., Yang, Z.-Y., van de Velde, H., and Stamatelos, S. K.
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- 2022
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25. Cost-Effective Thermal Control Planning for Mass Concrete Construction Using Nomograms.
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Park, Jisoo, Brown, Jason, Al-Hasani, Luna E., Gentry, T. Russell, Kurtis, Kimberly E., and Cho, Yong K.
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CONCRETE construction ,CONSTRUCTION projects ,NOMOGRAPHY (Mathematics) ,THERMODYNAMICS ,CONCRETE ,HEAT of hydration - Abstract
Since hydration heat generated during construction has been the cause of cracking and deformations in mass concrete structures, selecting appropriate thermal control plans is crucial in mass concrete construction. However, developing numerical models to predict the heat of hydration in mass concrete involves complex processes that demand extensive knowledge in thermodynamics and related fields, which can result in increased costs and extended timelines for construction methods and material selection. To address this problem, this research aims to develop a simple decision-making framework to select a cost-effective thermal control method using nomograms for materials and construction engineers. Several nomograms, including temperature and cost nomograms, were used to provide the most cost-effective thermal control plans while satisfying the maximum temperature limits of mass concrete. A case study of an actual construction project was used to validate and demonstrate the proposed framework. The effectiveness of this framework was demonstrated through a case study on a real construction project, which validated the approach and confirmed its potential to reduce the time required for developing thermal control plans in mass concrete construction projects. The findings from this study highlight the proposed framework's capability to streamline the thermal control method selection process, thereby facilitating a more intuitive understanding of thermal control options and markedly reducing both costs and time in mass concrete construction projects. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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26. A feasibility study for a Doppler reflectometer system in the JT-60SA tokamak
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Carralero, D., Happel, T., Estrada, T., Tokuzawa, T., Martínez, J., de la Luna, E., Cappa, A., and García, J.
- Published
- 2021
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27. Crossroads between Brazil and The United States: Eshu, Ogun and Oshunmare in Toni Morrison’s A Mercy and Conceição Evaristo’s Ponciá Vicêncio
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Danielle de Luna e Silva and Renan Cabral Paulino
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A Mercy ,Ponciá Vicencio ,Ogun ,Oshunmare ,Eshu ,Language and Literature ,English literature ,PR1-9680 - Abstract
This research of a bibliographical qualitative nature, aims at exposing the findings of the scientific investigation which comparatively studied A Mercy (2008), written by the North-American scholar, Toni Morrison and Ponciá Vicencio (2017) written by the Brazilian contemporary writer Conceição Evaristo, in order to list elements related to the presence of Orishas in the narratives. At the end of the study, it was noticed that there is, in both novels, evidence that are convergent to characteristics of Oshunmare, Ogun and Eshu. This latter was approached as an element that made possible the comparative reading of Afro-Brazilian and African-American Literature.
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- 2022
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28. Progress in preparing real-time control schemes for Deuterium-Tritium operation in JET
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Piron, L., Valcarcel, D., Lennholm, M., Stuart, C.I., Carvalho, I.S., Felton, R., Ferreira, D.R., Fontana, M., Lomas, P.J., La Luna, E. De, Peacock, A., Pau, A., Piron, C., Rimini, F., and Sozzi, C.
- Published
- 2021
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29. Non-perturbative QCD effects in forward scattering at LHC
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Bahia, C. A. S., Broilo, M., and Luna, E. G. S.
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High Energy Physics - Phenomenology ,High Energy Physics - Experiment - Abstract
We study infrared contributions to semihard parton-parton interactions by considering an effective charge whose finite infrared behavior is constrained by a dynamical mass scale. Using an eikonal QCD-based model in order to connect this semihard parton-level dynamics to the hadron-hadron scattering, we obtain predictions for the proton-proton ($pp$) and antiproton-proton ($\bar{p}p$) total cross sections, $\sigma_{tot}^{pp,\bar{p}p}$, and the ratios of the real to imaginary part of the forward scattering amplitude, $\rho^{pp,\bar{p}p}$. We discuss the theoretical aspects of this formalism and consider the phenomenological implications of a class of energy-dependent form factors in the high-energy behavior of the forward amplitude. We introduce integral dispersion relations specially tailored to relate the real and imaginary parts of eikonals with energy-dependent form factors. Our results, obtained using a group of updated sets of parton distribution functions (PDFs), are consistent with the recent data from the TOTEM, AUGER and Telescope Array experiments., Comment: 29 pages, 6 figures, 3 tables; version to be published in Phys. Rev. D
- Published
- 2015
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30. Energy-dependent dipole form factor in a QCD-inspired model
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Bahia, C. A. S., Broilo, M., and Luna, E. G. S.
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High Energy Physics - Phenomenology - Abstract
We consider the effect of an energy-dependent dipole form factor in the high-energy behavior of the forward amplitude. The connection between the semihard parton-level dynamics and the hadron-hadron scattering is established by an eikonal QCD-based model. Our results for the proton-proton ($pp$) and antiproton-proton ($\bar{p}p$) total cross sections, $\sigma_{tot}^{pp,\bar{p}p}(s)$, obtained using the CTEQ6L1 parton distribution function, are consistent with the recent data from the TOTEM experiment., Comment: 7 pages, 1 figure; Contribution to Proceedings of XIIIth International Workshop on Hadron Physics, Angra dos Reis, Brazil, 22-27 March, 2015
- Published
- 2015
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31. Limit on the pion distribution amplitude
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Luna, E. G. S. and Natale, A. A.
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High Energy Physics - Phenomenology ,High Energy Physics - Experiment ,High Energy Physics - Lattice - Abstract
The pion distribution amplitude (DA) can be related to the fundamental QCD Green's functions as a function of the quark self-energy and the quark-pion vertex, which in turn are associated with the pion wave function through the Bethe-Salpeter equation. Considering the extreme hard asymptotic behavior in momentum space allowed for a pseudoscalar wave function, which is limited by its normalization condition, we compute the pion DA and its second moment. From the resulting amplitude, representing the field theoretical upper limit on the DA behavior, we calculate the photon-pion transition form factor $F_{\pi\gamma\gamma^{\ast}}(Q^{2})$. The resulting upper limit on the pion transition form factor is compared with existing data published by CLEO, BaBar and Belle collaborations., Comment: 10 pages, 2 figures; version to appear in J. Phys. G
- Published
- 2014
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32. Investigation of III-V Nanowires by Plan-View Transmission Electron Microscopy: InN Case Study
- Author
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Luna, E, Grandal, J, Gallardo, E, Calleja, J M, Sánchez-García, M A, Calleja, E, and Trampert, A
- Subjects
Condensed Matter - Materials Science - Abstract
We discuss observations of InN nanowires (NWs) by plan-view high-resolution transmission electron microscopy (TEM). The main difficulties arise from suitable methods available for plan-view specimen preparation. We explore different approaches and find that the best results are obtained using a refined preparation method based on the conventional procedure for plan-view TEM of thin films, specifically modified for the NW morphology. The fundamental aspects of such a preparation are the initial mechanical stabilization of the NWs and the minimization of the ion-milling process after dimpling the samples until perforation. The combined analysis by plan-view and cross-sectional TEM of the NWs allows determination of the degree of strain relaxation and reveals the formation of an unintentional shell layer (2-3 nm thick) around the InN NWs. The shell layer is composed of bcc-In2O3 nanocrystals with a preferred orientation with respect to the wurtzite InN: In2O3 [111] || InN [0001] and In2O3 <110> || InN <11-20>.
- Published
- 2013
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33. A model of non-Maxwellian electron distribution function for the analysis of ECE data in JET discharges
- Author
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Giruzzi G., Fontana M., Orsitto F.P., de la Luna E., Dumont R., Figini L., Maslov M., Mazzi S., Schmuck S., Senni L., Sozzi C., Challis C., Frigione D., Garcia J., Garzotti L., Hobirk J., Kappatou A., Keeling D., Lerche E., Maggi C., Mailloux J., Rimini F., and Van Eester D.
- Subjects
Physics ,QC1-999 - Abstract
Recent experiments performed in JET at high level of plasma heating, in preparation of, and during the DT campaign have shown significant discrepancies between electron temperature measurements by Thomson Scattering (TS) and Electron Cyclotron Emission (ECE). In order to perform a systematic analysis of this phenomenon, a simple model of bipolar distortion of the electron distribution function has been developed, allowing analytic calculation of the EC emission and absorption coefficients. Extensive comparisons of the modelled ECE spectra (at both the 2nd and the 3rd harmonic extraordinary mode) with experimental measurements display good agreement when bulk electron distribution distortions around 1-2 times the electron thermal velocity are used and prove useful for a first level of analysis of this effect.
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- 2023
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34. Investigation of Te measurements discrepancies between ECE and Thomson diagnostics in high-performance plasmas in JET
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Fontana M., Giruzzi G., Orsitto F. P., de la Luna E., Dumont R., Figini L., Kos D., Maslov M., Schmuck S., Sozzi C., Challis C. D., Frigione D., Garcia J., Garzotti L., Hobirk J., Kappatou A., Keeling D., Lerche E., Maggi C., Mailloux J., Rimini F., and Van Eester D.
- Subjects
Physics ,QC1-999 - Abstract
For high-temperature JET and TFTR discharges, electron cyclotron emission (ECE) measurements of central electron temperature were systematically found to be up to 20% higher than those taken with Thomson scattering. In recent high-performance JET discharges, central Te measurements, performed with LIDAR Thomson scattering and the X-mode ECE interferometer, have been studied in a large database, including deuterium (DD), and deuterium-tritium plasmas (DT). Discrepancies between Te measurements have been observed outside of the experimental uncertainties. ECE measurements, at high Te, have been found to be higher or lower than those of LIDAR, depending on the specific plasma scenario. In addition, discrepancies between the peaks of the second and third harmonic ranges of the ECE spectrum have been interpreted as evidence for the presence of non-Maxwellian features in the electron distribution function. These comparisons seem to suggest that such features can be found in most of the high-performance scenarios selected in this JET database.
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- 2023
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35. Analytical and MonteCarlo approaches to infer the total gamma ray emission from the JET tokamak
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Marcer, G, Zohar, A, Dal Molin, A, Rigamonti, D, Rebai, M, Nocente, M, Panontin, E, Croci, G, Gorini, G, Grosso, G, Muraro, A, Perelli Cippo, E, Putignano, O, de la Luna, E, Ghani, Z, Conroy, S, Garcia, J, Kazakov, Y, Kiptily, V, Maslov, M, Nave, M, Ongena, J, Tardocchi, M, Marcer G., Zohar A., Dal Molin A., Rigamonti D., Rebai M., Nocente M., Panontin E., Croci G., Gorini G., Grosso G., Muraro A., Perelli Cippo E., Putignano O., de la Luna E., Ghani Z., Conroy S., Garcia J., Kazakov Y., Kiptily V., Maslov M., Nave M., Ongena J., Tardocchi M., Marcer, G, Zohar, A, Dal Molin, A, Rigamonti, D, Rebai, M, Nocente, M, Panontin, E, Croci, G, Gorini, G, Grosso, G, Muraro, A, Perelli Cippo, E, Putignano, O, de la Luna, E, Ghani, Z, Conroy, S, Garcia, J, Kazakov, Y, Kiptily, V, Maslov, M, Nave, M, Ongena, J, Tardocchi, M, Marcer G., Zohar A., Dal Molin A., Rigamonti D., Rebai M., Nocente M., Panontin E., Croci G., Gorini G., Grosso G., Muraro A., Perelli Cippo E., Putignano O., de la Luna E., Ghani Z., Conroy S., Garcia J., Kazakov Y., Kiptily V., Maslov M., Nave M., Ongena J., and Tardocchi M.
- Abstract
A single gamma-ray spectrometer installed at the end of a collimator can be used to infer the total emission from a tokamak plasma if the transport of gamma-rays from the plasma to the detector is known. In such analysis, the plasma emission profile plays a fundamental role, since it impacts the fraction of plasma volume intercepted by the detector line of sight. In this work, the DT 17 MeV fusion gamma-rays emission profile of the JET discharge #99608 from second 46 to 48 has been estimated both with the TRANSP code and reconstructed through tomographic inversion based on the neutron camera data, assuming that fusion gamma-rays have the same profile as the 14 MeV fusion neutrons. The gamma-ray transport has been evaluated both by MonteCarlo simulations and analytical calculations. By combining MonteCarlo and analytical evaluations of the gamma-ray transport in different ways with the estimated radiation emission profile, we provide four different routes to determine the total gamma-ray yield from measurements whose results agree within better than 10%.
- Published
- 2023
36. XIX NATIONAL MEETING OF THE ITALIAN SOCIETY FOR PLANT PATHOLOGY (SIPaV): Padova, September 23-25, 2013: Abstracts of papers
- Author
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Delbianco, A., Bertolini, P., Bosco, D., De Nicolao, G., Luna, E., Lopez, A., Neal, A., Ton, J., Pennacchio, F., Scala, A., Scala, F., Rossi, V., Schäfer, W., Schulz, S.B., Junker, C., Haas, S., Schobert, M., Citron, C., and Dickschat, J.
- Published
- 2013
37. Cross sections, multiplicity and moment distributions at the LHC
- Author
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Beggio, P. C. and Luna, E. G. S.
- Subjects
High Energy Physics - Phenomenology - Abstract
The unitarity of the $S$-matrix requires that the absorptive part of the elastic scattering amplitude receives contributions from both the inelastic and the elastic channels. We explore this unitarity condition in order to describe, in a connected way, hadron-hadron observables like the total and elastic differential cross sections, the ratio of the real to imaginary part of the forward scattering amplitude and the inclusive multiplicity distributions in full phase space, over a large range of energies. We introduce non-perturbative QCD effects in the forward scattering amplitude by using the infrared QCD effective charge dependent on the dynamical gluon mass. In our analysis we pay special attention to the theoretical uncertainties in the predictions due to this mass scale variation. We also present quantitative predictions for the $H_{q}$ moments at high energies. Our results reproduce the moment oscillations observed in experimental data, and are consistent with the behavior predicted by QCD., Comment: 26 pages, 8 figures, discussion extended, references added; version to appear in Nucl. Phys. A
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- 2013
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38. #VacinaMare campaign: addressing vaccine inequity in socially vulnerabilised communities
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Batista-da-Silva, Amanda A., Bastos, Leonardo S.L., Arouca, Luna E., Gonzaga-da-Silva, Thiago W., Hamacher, Silvio, Bozza, Fernando A., and Ranzani, Otavio T.
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- 2024
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39. Design and measuring performance of the ITER plasma position reflectometer in-port-plug antennas
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Martínez-Fernández, J., Cappa, Á., Estrada, T., de la Luna, E., and Blanco, E.J.
- Published
- 2019
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40. Aspects of a dynamical gluon mass approach to elastic hadron scattering at LHC
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Fagundes, D. A., Luna, E. G. S., Menon, M. J., and Natale, A. A.
- Subjects
High Energy Physics - Phenomenology ,High Energy Physics - Experiment - Abstract
We discuss how the main features of the recent LHC data on elastic scattering can be described by a QCD-inspired formalism with a dynamical infrared mass scale. For this purpose new developments on a dynamical gluon mass approach are reported, with emphasis on a method to estimate uncertainty bounds in the predictions for the high-energy scattering observables. We investigate the effects due to the correlations among the fixed and free parameters involved and show that the band of predictions are consistent with the recent data from the TOTEM experiment, including the forward quantities and the differential cross section up to the dip position., Comment: 19 pages, 7 figures, 5 tables. Discussion extended, references added, typos corrected, to be published in Nucl. Phys. A
- Published
- 2011
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41. Testing parameters in an eikonalized dynamical gluon mass model
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Fagundes, D. A., Luna, E. G. S., Menon, M. J., and Natale, A. A.
- Subjects
High Energy Physics - Phenomenology - Abstract
In the framework of a dynamical gluon mass model recently developed, we investigate the effects of two essential parameters in the description of elastic $pp$ and $\bar{p}p$ data at high energies: the soft Pomeron intercept and the dynamical gluon mass. By considering relevant numerical intervals for both parameters and fits to the experimental data up to 1.8 TeV, with good statistical results, we discuss the predictions of the physical quantities at the LHC energies (7 and 14 TeV). We conclude that these quantities are sensitive to those variations and the predictions are correlated with the intervals considered for both parameters. This conclusion puts limits on the reliability of QCD inspired models predictions at the LHC energies, mainly those models with ad hoc fixed values for the mass scale and the Pomeron intercept., Comment: misprints corrected, one reference updated and minor changes
- Published
- 2011
42. Diffraction phenomenology with massive gluons: some recent developments
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Luna, E. G. S.
- Subjects
High Energy Physics - Phenomenology ,High Energy Physics - Experiment ,High Energy Physics - Lattice - Abstract
In this talk we introduce the main features of a QCD-based model in which the coupling $\alpha_{s}$ is constrained by an infrared mass scale. We show recent applications of this model to hadron-hadron collisions, gap survival probability calculations, and soft gluon resummation techniques. These results indicate a smooth transition from non-perturbative to perturbative behaviour of the QCD., Comment: Invited keynote talk at Diffractive and Electromagnetic Processes at the LHC, Trento, Italy, January 2010; invited talk at XI Hadron Physics, Maresias, Brazil, March 2010
- Published
- 2011
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43. QCD effective charge and the structure function $F_{2}$ at small-$x$
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Luna, E. G. S., Natale, A. A., and Santos, A. L. dos
- Subjects
High Energy Physics - Phenomenology ,High Energy Physics - Experiment ,High Energy Physics - Lattice - Abstract
We study infrared contributions to the QCD description of the HERA data on the structure function $F_{2}$ within the \textit{generalized} DAS approximation. We argue that this approximation is a natural one and consistent with the phenomenon of dynamical mass generation in QCD. The investigation is performed at next-to-leading order by using the leading-twist expansion of $F_{2}(x,Q^{2})$ and by adopting an effective charge whose finite infrared behavior is constrained by a dynamical gluon mass. We propose one ansatz for the behavior of this effective coupling beyond leading order. The dependence of the experimental data on the infrared value of the effective charge is used in order to study the asymptotic behavior of the running gluon mass. The deep inelastic structure function $F_{2}$ obtained in this approach shows very good agreement with the experimental data., Comment: 20 pages, 2 figures, references and remarks added, version to appear in PLB
- Published
- 2010
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44. The possibility that the triple-Pomeron coupling vanishes at q_t=0
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Luna, E. G. S., Khoze, V. A., Martin, A. D., and Ryskin, M. G.
- Subjects
High Energy Physics - Phenomenology - Abstract
We study the case when the triple-Pomeron vertex is assumed to have a vectorial form, that is, the amplitude of high-mass diffractive dissociation vanishes as $V \propto \vec q_t \cdot \vec e$ as $q_t \to 0$. We find that the available data in the triple-Reggeon region may be well described in such a `weak' coupling scenario, providing that absorptive effects are taken into account. We compare this weak (vector) coupling scenario with the strong and weak (scalar) coupling scenarios. Corresponding predictions are presented for an LHC energy of 14 TeV., Comment: 13 pages, 6 figures
- Published
- 2010
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45. Observation of confined current ribbon in JET plasmas
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Solano, E. R., Lomas, P. J., Alper, B., Xu, G. S., Andrew, Y., Arnoux, G., Boboc, A., Barrera, L., Belo, P., Beurskens, M. N. A., Brix, M., Crombe, K., de la Luna, E., Devaux, S., Eich, T., Gerasimov, S., Giroud, C., Harting, D., Howell, D., Huber, A., Kocsis, G., Korotkov, A., Lopez-Fraguas, A., Nave, M. F. F., Rachlew, E., Rimini, F., Saarelma, S., Sirinelli, A., Thomsen, H., Zabeo, L., Zarzoso, D., and contributors, JET EFDA
- Subjects
Physics - Plasma Physics - Abstract
we report the identification of a localised current structure inside the JET plasma. It is a field aligned closed helical ribbon, carrying current in the same direction as the background current profile (co-current), rotating toroidally with the ion velocity (co-rotating). It appears to be located at a flat spot in the plasma pressure profile, at the top of the pedestal. The structure appears spontaneously in low density, high rotation plasmas, and can last up to 1.4 s, a time comparable to a local resistive time. It considerably delays the appearance of the first ELM., Comment: 10 pages, 6 figures
- Published
- 2009
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46. Diffractive dissociation re-visited for predictions at the LHC
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Luna, E. G. S., Khoze, V. A., Martin, A. D., and Ryskin, M. G.
- Subjects
High Energy Physics - Phenomenology - Abstract
We describe the formalism, and present the results, for a triple-Regge analysis of the available pp and p\bar{p} high-energy data which explicitly accounts for absorptive corrections. In particular, we allow for the gap survival probability, S^2, in single proton diffractive dissociation. Since for pp scattering the value of S^2 is rather small, the triple-Pomeron vertex obtained in this analysis is larger than that obtained in the old analyses where the suppression caused by the absorptive corrections was implicitly included in an effective vertex. We show that the bare triple-Pomeron coupling that we extract from the pp and p\bar{p} data is consistent with that obtained in a description of the gamma p -> J/psi + Y HERA data. The analyses of the data prefer a zero slope, corresponding to the small size of the bare vertex, giving the hope of a smooth matching to the perturbative QCD treatment of the triple-Pomeron coupling., Comment: 26 pages, 12 figures; two figures added, references added, version to appear in Eur.Phys.J.C
- Published
- 2008
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47. Diffraction and an infrared finite gluon propagator
- Author
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Luna, E. G. S.
- Subjects
High Energy Physics - Phenomenology - Abstract
We discuss some phenomenological applications of an infrared finite gluon propagator characterized by a dynamically generated gluon mass. In particular we compute the effect of the dynamical gluon mass on $pp$ and ${\bar{p}}p$ diffractive scattering. We also show how the data on $\gamma p$ photoproduction and hadronic $\gamma \gamma$ reactions can be derived from the $pp$ and $\bar{p}p$ forward scattering amplitudes by assuming vector meson dominance and the additive quark model., Comment: 4 pages, 7 figures, added references and figures, changed structure. Contribution to Proceedings of XVIIIth Reuniao de Trabalho sobre Interacoes Hadronicas, Sao Paulo, Brazil, 22-24 May, 2006
- Published
- 2006
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48. Survival probability of large rapidity gaps in a QCD model with a dynamical infrared mass scale
- Author
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Luna, E. G. S.
- Subjects
High Energy Physics - Phenomenology ,High Energy Physics - Experiment - Abstract
We compute the survival probability $<|S|^{2}>$ of large rapidity gaps (LRG) in a QCD based eikonal model with a dynamical gluon mass, where this dynamical infrared mass scale represents the onset of nonperturbative contributions to the diffractive hadron-hadron scattering. Since rapidity gaps can occur in the case of Higgs boson production via fusion of electroweak bosons, we focus on $WW\to H$ fusion processes and show that the resulting $<|S|^{2}>$ decreases with the increase of the energy of the incoming hadrons, in line with the available experimental data for LRG. We obtain $<|S|^{2} > = 27.6\pm7.8$ % ($ 18.2\pm7.0$ %) at Tevatron (CERN-LHC) energy for a dynamical gluon mass $m_{g}=400$ MeV., Comment: 15 pages, 2 figures, added some comments and new references. To appear in Physics Letters B
- Published
- 2006
- Full Text
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49. The small $x$ behavior of the gluon structure function from total cross sections
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Luna, E. G. S., Natale, A. A., and Zanetti, C. M.
- Subjects
High Energy Physics - Phenomenology - Abstract
Within a QCD-based eikonal model with a dynamical infrared gluon mass scale we discuss how the small $x$ behavior of the gluon distribution function at moderate $Q^{2}$ is directly related to the rise of total hadronic cross sections. In this model the rise of total cross sections is driven by gluon-gluon semihard scattering processes, where the behavior of the small $x$ gluon distribution function exhibits the power law $xg(x,Q^2)= h(Q^2)x^{-\epsilon}$. Assuming that the $Q^{2}$ scale is proportional to the dynamical gluon mass one, we show that the values of $h(Q^2)$ obtained in this model are compatible with an earlier result based on a specific nonperturbative Pomeron model. We discuss the implications of this picture for the behavior of input valence-like gluon distributions at low resolution scales., Comment: 19 pages, 3 figures; revised version; to appear in Int. J. Mod. Phys. A
- Published
- 2006
- Full Text
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50. $\gamma p$ and $\gamma \gamma$ scattering from $\bar{p}p$, $pp$ forward amplitudes in a QCD eikonal model with a dynamical gluon mass
- Author
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Luna, E. G. S. and Natale, A. A.
- Subjects
High Energy Physics - Phenomenology - Abstract
We examine the $\gamma p$ photoproduction and the hadronic $\gamma \gamma$ total cross sections by means of a QCD eikonal model with a dynamical infrared mass scale. In this model, where the dynamical gluon mass is the natural regulator for the tree level gluon-gluon scattering, the $\gamma p$ and $\gamma \gamma$ total cross sections are derived from the $pp$ and $\bar{p}p$ forward scattering amplitudes assuming vector meson dominance and the additive quark model. We show that the validity of the cross section factorization relation $\sigma_{pp}/\sigma_{\gamma p}=\sigma_{\gamma p}/\sigma_{\gamma \gamma}$ is fulfilled depending on the Monte Carlo model used to unfold the hadronic $\gamma \gamma$ cross section data, and we discuss in detail the case of $\sigma (\gamma \gamma \to hadrons)$ data with $W_{\gamma \gamma} > 10$ GeV unfolded by the Monte Carlo generators PYTHIA and PHOJET. The data seems to favor a mild dependence with the energy of the probability ($P_{had}$) that the photon interacts as a hadron., Comment: 16 pages, 3 figures; misprints corrected; to appear in Phys. Rev. D
- Published
- 2006
- Full Text
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