63 research outputs found

    Finite angle effects in jet quenching

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    The medium that forms in a heavy-ion collision modifies the properties of jets traversing it. These modifications give substantial information about the nature of the medium and, therefore, they are one of the main focuses of the heavy-ion program at LHC. The influence of the medium into highly energetic partons depends on correlators of Wilson lines, which have been studied in perturbation theory and in several phenomenological models. Here, we focus on the antenna configuration, the study of the evolution of the large energy partons resulting from a collinear splitting inside of the medium. In the eikonal limit, the interaction of each daughter parton with the medium can be parametrized by a light-like Wilson line in a given direction. We consider the case in which the angle between these two directions θ is small but such that Lθ is of the order of the medium resolution scale, where L is the size of the medium. We find that finite angle effects give sub-leading corrections to jet broadening. The physical effect in the antenna configuration is to make the decoherence effect larger when finite angle corrections are taken into account

    La admisibilidad y el valor probatorio de la evidencia digital en el Sistema Jurídico Peruano 2018

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    La presente investigación titulada: La admisibilidad y el valor probatorio de la evidencia digital en el Sistema Jurídico Peruano, 2018; tuvo como objetivo general conocer y establecer los procedimientos en la investigación, manejo y traslado de la evidencia digital, dentro de la actividad probatoria que se fundamente por un lado, teniendo en cuenta lo establecido por la ley, y por otro los procedimientos técnicos mediante el empleo de herramientas tecnológicas. El método empleado fue deductivo, el tipo de investigación fue básica, de nivel descriptivo, de enfoque cualitativo, de diseño no experimental. La población estuvo formada por fiscal representante del Ministerio Publico, personal PNP especialista en delitos de alta tecnología representante de la Policía Nacional del Perú, y un experto de tecnologías en delitos financieros del sistema bancario. La técnica empleada para recolectar información fue la observación, entrevista, análisis documental y los instrumentos de recolección de datos fueron, cuestionarios, guía de observación, guía de entrevista. Se llegaron a las siguientes conclusiones: La prueba digital no solo es insuficiente, sino, no cuenta con un tratamiento especial en el Nuevo Código Procesal Penal del 2004, así como los operadores de justicia jueces, fiscales, abogados litigantes y el personal de la Policía Nacional no están capacitados en el manejo de procedimientos de hallazgo, recojo, tratamiento y traslado de las evidencias digitales

    Peanut Shell for Energy: Properties and Its Potential to Respect the Environment

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    The peanut (Arachys hypogaea) is a plant of the Fabaceae family (legumes), as are chickpeas, lentils, beans, and peas. It is originally from South America and is used mainly for culinary purposes, in confectionery products, or as a nut as well as for the production of biscuits, breads, sweets, cereals, and salads. Also, due to its high percentage of fat, peanuts are used for industrialized products such as oils, flours, inks, creams, lipsticks, etc. According to the Food and Agriculture Organization (FAO) statistical yearbook in 2016, the production of peanuts was 43,982,066 t, produced in 27,660,802 hectares. Peanuts are grown mainly in Asia, with a global production rate of 65.3%, followed by Africa with 26.2%, the Americas with 8.4%, and Oceania with 0.1%. The peanut industry is one of the main generators of agroindustrial waste (shells). This residual biomass (25–30% of the total weight) has a high energy content that is worth exploring. The main objectives of this study are, firstly, to evaluate the energy parameters of peanut shells as a possible solid biofuel applied as an energy source in residential and industrial heating installations. Secondly, different models are analysed to estimate the higher heating value (HHV) for biomass proposed by different scientists and to determine which most accurately fits the determination of this value for peanut shells. Thirdly, we evaluate the reduction in global CO2 emissions that would result from the use of peanut shells as biofuel. The obtained HHV of peanut shells (18.547 MJ/kg) is higher than other biomass sources evaluated, such as olive stones (17.884 MJ/kg) or almond shells (18.200 MJ/kg), and similar to other sources of biomass used at present for home and industrial heating applications. Different prediction models of the HHV value proposed by scientists for different types of biomass have been analysed and the one that best fits the calculation for the peanut shell has been determined. The CO2 reduction that would result from the use of peanut shells as an energy source has been evaluated in all production countries, obtaining values above 0.5 ‰ of their total emissions

    Heavy quarkonium moving in a quark-gluon plasma

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    By means of effective field theory techniques, we study the modifications of some properties of weakly coupled heavy quarkonium states propagating through a quark-gluon plasma at temperatures much smaller than the heavy quark mass, mQ. Two different cases are considered, corresponding to two different hierarchies between the typical size of the bound state, r, the binding energy, E, the temperature, T, and the screening mass, mD. The first case corresponds to the hierarchy mQ≫1/r≫T≫E≫mD, relevant for moderate temperatures, and the second one to the hierarchy mQ≫T≫1/r, mD≫E, relevant for studying the dissociation mechanism. In the first case we determine the perturbative correction to the binding energy and to the decay width of states with arbitrary angular momentum, finding that the width is a decreasing function of the velocity. A different behavior characterizes the second kinematical case, where the width of s-wave states becomes a nonmonotonic function of the velocity, increasing at moderate velocities and decreasing in the ultrarelativistic limit. We obtain a simple analytical expression of the decay width for T≫1/r≫mD≫E at moderate velocities, and we derive the s-wave spectral function for the more general case T≫1/r, mD≫E. A brief discussion of the possible experimental signatures as well as a comparison with the relevant lattice data are also presented

    Bottomonium suppression in an open quantum system using the quantum trajectories method

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    We solve the Lindblad equation describing the Brownian motion of a Coulombic heavy quark-antiquark pair in a strongly coupled quark-gluon plasma using the highly efficient Monte Carlo wave-function method. The Lindblad equation has been derived in the framework of pNRQCD and fully accounts for the quantum and non-Abelian nature of the system. The hydrodynamics of the plasma is realistically implemented through a 3+1D dissipative hydrodynamics code. We compute the bottomonium nuclear modification factor and compare with the most recent LHC data. The computation does not rely on any free parameter, as it depends on two transport coefficients that have been evaluated independently in lattice QCD. Our final results, which include late-time feed down of excited states, agree well with the available data from LHC 5.02 TeV PbPb collisions.Comment: 42 pages, 18 figure

    Heavy quarkonium dynamics at next-to-leading order in the binding energy over temperature

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    Using the potential non-relativistic quantum chromodynamics (pNRQCD) effective field theory, we derive a Lindblad equation for the evolution of the heavy-quarkonium reduced density matrix that is accurate to next-to-leading order (NLO) in the ratio of the binding energy of the state to the temperature of the medium. The resulting NLO Lindblad equation can be used to more reliably describe heavy-quarkonium evolution in the quark-gluon plasma at low temperatures compared to the leading-order truncation. For phenomenological application, we numerically solve the resulting NLO Lindblad equation using the quantum trajectories algorithm. To achieve this, we map the solution of the three-dimensional Lindblad equation to the solution of an ensemble of one-dimensional Schr\"odinger evolutions with Monte-Carlo sampled quantum jumps. Averaging over the Monte-Carlo sampled quantum jumps, we obtain the solution to the NLO Lindblad equation without truncation in the angular momentum quantum number of the states considered. We also consider the evolution of the system using only the complex effective Hamiltonian without stochastic jumps and find that this provides a reliable approximation for the ground state survival probability at LO and NLO. Finally, we make comparisons with our prior leading-order pNRQCD results and experimental data available from the ATLAS, ALICE, and CMS collaborations.Comment: 40 pages, 8 figure

    Batteryless NFC dosimeter tag for ionizing radiation based on commercial MOSFET

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    This paper reports the development, evaluation and validation of DosiTag, a dosimetric platform based on Near Field Communication (NFC) technology. The designed system comprises two main parts: a passive NFC sensing tag as the dosimeter unit, which includes a commercial P-channel MOSFET transistor as radiation sensor; and an NFC-enabled smartphone running a custom-developed application as the reader unit. Additionally, a cloud service based on the messaging protocol Message Queue Telemetry Transport (MQTT) has been implemented using a broker/client architecture to allow the storage and classification of the patient’s data. The dosimeter tag was designed using commercial low-power integrated circuits (ICs) and it can operate without any external power supply or battery, being supplied by the smartphone through the radio frequency (RF) energy harvested from the NFC link. The radiation dose is measured through the increase of the DMOS transistor source voltage using the smartphone as the reader unit. Two tag prototypes have been characterized with a 6 MV photon beam and radiation doses up to 57 Gy and 42 Gy, respectively. The achieved average sensitivity is (4.37 ± 0.04) mV/ Gy with a resolution of 2 cGy, which goes beyond the state-of-the-art of previous NFC dosimeters and places DosiTag as a low-cost promising electronic platform for dose control in radiotherapy treatments.Junta de Andalucía (Spain), projects numbers PI-0505–2017 FEDER/Junta de Andalucía- Consejería de Economía y Conocimiento Project B-TIC-468-UGR18Proyecto del Plan Nacional I + D: PID2019–104888GB-I00 and Proyectos I + D + i Junta de Andalucía 2018: P18-RT-3237H2020 ELICSIR project (grant No. 857558)Grant IJC2020-043307-I funded by MCIN/AEI/ 10.13039/501100011033European Union NextGenerationEU/ PRT
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