In theories of quantum gravity it is challenging to define notions of quantum entanglement between different regions of space. We will argue that a precise notion is, however, possible in gravitational theories which are holographically dual to usual quantum field theories in some fixed background living in lower number of dimensions. This is provided by the notion of "target space...
Acoustic analogue of a black hole has been a lot studied in the literature as a concrete laboratory model for probe several aspects of curved space quantum field theory.
In 1981, Unruh showed that if a fluid is barotropic and inviscid,and the flow of the fluid is irrotational, the equation of motion that fluctuation of the velocity potential of acoustic disturbance obeys, is identical to that...
Primero estudiamos las órbitas planetarias mediante la formulación de Newton y mostramos que las órbitas son cerradas; es decir no describe adecuadamente la desviación de la periapsis de Mercurio.
Comenzamos reduciendo el movimiento de dos cuerpos al de uno solo en un campo central. Construimos la energía total manteniendo la conservacion de momento angular hallamos la integral de movimiento....
La Física, en particular, ha contribuido en diferentes aspectos y avances en el campo de la investigación sobre el cáncer; esta cienciaposee un marcoteórico que permite explicar las propiedades y funcionamiento de las moléculas (en sub-disciplinas como la mecánica cuántica, la mecánica estadística y la electrodinámica cuántica) y que se pueden ...
Investigaciones anteriores en nanopartículas de dopadas con tierras raras trivalentes, muestran que tienen propiedades luminiscentes por upconversión prometedoras para utilizarlas en el campo de la biomedicina, por su alta sensibilidad y bajo ruido de fondo. En este trabajo reportamos la obtención de nanopartículas β-NaYF4:Ho3+/Yb3+ por el método solvotermal sin tratamiento térmico, con...
I'll describe how to test cosmological models with large galaxy surveys, focusing on the Dark Energy Collaboration that in 5 years has collected data from more than 300 million galaxies.
Despite the fact that the integral form of the equations of classical electrodynamics is well known, the same is not true for non-abelian gauge theories. In this talk we present the integral form of the classical Yang-Mills equations in the presence of sources and then use it to solve the long standing problem of constructing non-abelian electric and magnetic conserved charges, for any field...
The pure spinor formalism has been shown to be extremely useful for quantizing superstrings and computing scattering amplitudes in a manifestly super-Poincaré covariant way. An 11D generalization gave rise to the pure spinor description of supermembranes whose massless spectrum reproduces 11D supergravity. In this talk, I will discuss how the infinite tension limit of the pure spinor...
La presente investigación tiene como objetivo proponer actividades experimentales como estrategia didáctica para facilitar el aprendizaje de la Física en los estudiantes de ingenierías de la Universidad Nacional de Juliaca. La muestra y la población está conformada por 45 estudiantes de las diferentes áreas de Física. Para lo cual se trabajó con dos grupos uno grupo A a quienes se le aplicó...
An epidemic simulation of Covid-19 virus was made, it was done using cellular automatas wich have been used for epidemic studies since their creation in XX century. Under the current situation due to the Covid-19 virus there have been various estimates of the advance of the decease using a lot of methods, however most of them fail to calculate the total number of not-sick infected. Based on...
Estudios dosimetricos publicados demuestran que el algoritmo 'pencil beam' (PB) sobreestima la dosis calculada en volumenes de tratamiento en presencia de heterogeneidades en especial en la region correspondiente a la interfase aire-tejido. El porcentaje de sobreestimacion de dosis depende de la localizacion relativa del tumor, de alli que es imprescindible contar con un algoritmo de calculo...
Memory effects in open systems dynamics have been the subject of significant interest in the last decades. Methods quantifying this effect, however, are often difficult to compute and lack analytical insight. With this in mind, we consider Gaussian collisional models, where non-Markovianity is introduced by means of interactions between neighboring environments. We show that the dynamics can...
Measurement of indoor radon (Rn-222) concentration is important due to the impact of radon on indoor air quality and consequent inhalation hazard. This work presents the results of the radon (Rn-222) measurements made with LR-115 solid state detectors in bare mode at different distances from two opposite walls within two rooms in a home located in the north of Lima. The rooms differ by the...
Water vapor is the main cause of atmospheric attenuation at high frequencies. The
measurement of atmospheric opacity (τ ) is important because it allows us to obtain the
true brightness temperature of an astrophysical object. Melo et al. (2005), presented
the method of brightness of the Sun to determine atmospheric opacity in sub-millimeter
waves. Then, using the same method Cornejo et al....
Las nanopartículas magnéticas esféricas tipo núcleo-coraza Fe/MgO, poseen un gran potencial para aplicaciones de hipertermia magnética. Estas nanopartículas satisfacen algunos de los requisitos técnicos para el uso práctico en clínicas reales, como una alta biocompatibilidad en células vivas in vitro [1]. Investigaciones actuales han demostrado que las interacciones dipolares entre...
RESUMEN
La ocurrencia del evento El Niño trae consigo, serias implicaciones a escala global generando cambios en los sistemas costero-oceánicos, terrestres y atmosféricos [1]; tales como la elevación de la temperatura del mar, lluvias intensas, sequías, entre otras [2]; los cuales ocasionan serios problemas socio - económicos en países vinculados con la zona ecuatorial. En el Perú, estos...
Urban archeology represents the most suitable tool to start a global analysis of the historical, political and social events that affected cities over time. In this work, urban geophysics is used as a tool to explore the archeologically sensitive areas that are located inside the subsoil of the ancient city of Cusco. This objective takes shape after that inca walls were found in an area of...
In the last decade, wireless transfer of energy using resonant inductive systems has found many applications, from contactless charging of cell phones and medical implants to recharging electric ferries and boats. For the next decade, the most promising area for this technology is estimated to be charging batteries of electric cars and buses. Currently this charging operation is made by...
Molecular motors transduce chemical energy –usually from ATP hydrolysis– into directed motion and mechanical work, which is used to perform key functions in almost every cellular process. Molecular motors are particularly important in the maintenance of cellular proteostasis, i.e. the equilibrium between protein synthesis and degradation. ATP-dependent ...
Las ferritas (MFe2O4) son una de las familias de materiales magnéticos más estudiados tanto desde el punto de vista básico como aplicado. Las ferritas cristalizan en la estructura espinela y poseen dos sitios para los cationes, A y B. Esta característica hace que sus propiedades magnéticas de estos óxidos dependan de la distribución de cationes en las subredes de sitios A y B. El acoplamiento...
I will show concluded and current experimental work done at the Center for Quantum Devices, Copenhagen [1,2] and at CEA, Grenoble [3,4]. The work is based on electrical measurements at (sub-Kelvin) dilution-refrigerator temperatures on devices based on individual semiconductor nanowires with epitaxially-grown superconductors. Single electron spins can be confined in the nanowires, and their...
The adaptability of synthetic antiferromagnets (SAF) in spintronic devices based on spin Hall effects has emerged during the last years. In this work we report the use of a SAF (antiferromagnetically exchange coupled Co/Ru/Co) as a spin current injector and the observation of spin pumping and inverse spin Hall effect in [SAF]/Pt heterostructures [1,2]. By exploiting the interlayer exchange...
En el presente trabajo, a partir del estudio estructural y magnético de la aleación AlxFe(1-x) con x=0,25; 0,5 y 0,75, se plantea el Hamiltoniano magnético. Primero las muestras fueron sintetizadas por la técnica de horno de arco (HA) y posteriormente fueron tratadas a las temperaturas de 600 C, 950C y 1000C por 48, 290 y 48 horas respectivamente. Después del tratamiento térmico...
Two dimensional materials have provided unique insights in condensed matter physics, yielding a multitude of novel effects. Among them, graphene has shown to be an outstanding material owing to its exceptional and tunable electrical properties. In graphene, spin information can propagate over long distances and also be manipulated by proximity induced phenomena [1,2,3], providing thus the...
Resumen: En el contexto actual de la pandemia COVID-19 y debido al incremento acelerado de los casos en nuestro país, lo cual generó que nuestro sistema de salud muestre sus deficiencias no logrando responder ante la demanda, muchos de los dispositivos médicos que se utilizan para el tratamiento de los paciente se volvieron rápidamente insuficientes, creando la necesidad de optar por otras...
La pandemia del COVID-19 ocasionada por el virus SARS-CoV-2 requiere urgentemente el desarrollo de vacunas y tratamientos, para controlar la transmisión y mortalidad, y permitir que las sociedades puedan regresar a sus actividades normales.
Nuestro grupo ha desarrollado dos variantes de vacunas potenciales.
La primera variante es una proteína recombinante. Hemos producido cuatro antígenos,...
Los gases traza atmosféricos, presentes en concentraciones muy bajas (órdenes de ppb y ppt), tales como el ozono O3, óxidos de nitrógeno NOx (NO + NO2), radicales nitrato NO3 e hidroxilo OH, ácido nitroso HONO, óxidos de halógenos XO (X= Cl, Br, I), etc. pueden alterar la capacidad oxidativa de la atmósfera a través de procesos, que incluyen ciclos catalíticos, como la destrucción de la capa...
The Nancy Grace Roman Space Telescope is scheduled to be launched in the mid 2020’s. It is designed to investigate dark energy and dark matter, search for and characterize exoplanets and study many topics in infrared astrophysics. Roman Space Telescope 2.4m primary is the same size as Hubble’s, but Roman’s Wide Field Instrument has a field of view that is 100 times larger (approximately 0.3...
Dentro de los multiferroicos la ferrita de Bismuto (BiFeO3) es uno de los sistemas más estudiados. Este material presenta propiedades ferromagnéticas, ferroeléctricas y ópticas observadas a temperatura ambiente, que le permite ser aplicable para dispositivos de almacenamiento de datos y fotovoltaicos. [1]
El estudio comprende en la variación de la temperatura (0°C, 500°C y 600°C) en la...
Continuous global monitoring of lightning has been important in recent years to study a possible relationship with global warming. Consequently, several networks to detect lightning have been installed at various spatial scales (regional and global). One of these networks is the World Wide Lightning Location Network (WWLLN), which has been monitoring lightnings since 2003. It is also important...
Remarkable progress has been made in the last years to the use solar energy as a renewable and clean energy source. In this regard, Cu2S is a promising material for solar cell devices due to their electronic and optical properties. In this work, polycrystalline Cu2S films were grown onto borosilicate glass substrates with different thicknesses tuning by the deposition time at room temperature...
The Cosmic Microwave Background (CMB) is an open window to the early Universe. To compute the CMB Spectrum we need to perturb the FLRW metric that describes a homogeneous and isotropic universe at large scales. Furthermore, at early times photons have interacted with electrons by Compton scattering, before traveling through the space-time toward us. This interaction produces a perturbation in...
Abstract:
In the current context of modern cosmology, many models require the incorporation of non-minimally coupled scalar fields to the Ricci curvature scalar in order to explain some properties of the Universe on large scales [1]. These scalar-tensor theory models can be described by a generic action [2].
A frame transformation in scalar-tensor theories is equivalent to a local...
Magnetite (Fe3O4) nanoparticles (NPs) coated with organic material are of considerable interest in many biomedical applications, such as magnetic resonance imaging, drug administration, magneto-impedance tumor detection, magnetic hyperthermia, among others. Additionally, these nanostructured systems experience changes in their magnetic properties due to the reduced size, crystallite shape,...
We show different forms to calculate the sound horizon scale at baryon
drag epoch, $r_{drag}$, a physical parameter considered a cosmological
standard ruler. This important parameter supports recent studies of the
large-scale structure of the Universe, including the dynamics of its evolution.
For this, one of the aims of current astronomical surveys is to know this
parameter with high...
The conservation law for the total (orbital and spin) angular momentum of a Dirac particle in the presence of gravity requires that spacetime is not only curved, but also has a nonzero torsion.
The coupling between the spin and torsion in the Einstein-Cartan theory of gravity generates gravitational repulsion at extremely high densities.
We consider gravitational collapse of a spin-fluid...
In this work, we investigate various BTZ spacetimes [1] affected by linearized spherically symmetric perturbations of the metric analyzing the effects in the causal structure. In particular, we found that null rays can reach disconnected causal regions in the original background if there exists a violation of the averaged null energy condition (ANEC), generating a traversable wormhole [2]. The...
Las nubes moleculares son las regiones más densas y frías del gas molecular presente en el
medio interestelar de las Galaxias. En estas regiones se favorece la formación de la molécula
𝐻2, en donde también coexiste el polvo interestelar que actúan como catalizador ,para formar
otras moléculas y que actúa como sitio de protección a la radiación UV de estrellas cercanas .
El estudio de nubes...
Abstract:
The usual approach for the development of general relativity as a field theory is based on a Lagrangian formulation. But for some purposes (numerical relativity and canonical quantization) an approach from the point of view of the Hamiltonian formalism is preferable since it naturally describes the evolution of fields. Because this formulation requires the choice of a temporal...
Transparent conductive oxides (TCOs) coatings play an important role in several optoelectronic applications, such as transparent electrodes in liquid-crystal displays (LCDs), organic light-emitting diodes (OLEDs), solar cells, and light-emitting diodes [1-3]. One of the most prominent TCOs for decades has been tin-doped indium oxide, also known as indium tin oxide or simply ITO [4]. This...
In the present work, we carry out simulations to study the development of particle showers generated by photons as primary cosmic rays. We aim to determine whether or not it is possible to detect a Gamma Ray Burst (GRB) generated by an external source to the Earth with a Cherenkov detector placed at 4600 msnm.
We compare the results of the simulations with theoretical models that describe the...
El presente es un estudio acerca de la propagación de solitones brillantes NLS en un régimen de alta potencia en una lámina de grafeno trabajado computacionalmente, donde la variación de la fracción de energía fluyente dentro de la lámina provoca variacion en los picos solitónicos propagantes (se trabajó para fracciones 0.6, 0.8 y 1.0), los cuales al ser comparados en unidad relativa, permite...
In the study of the stellar structures, some models arises to explain their interior dynamics and surface consequences (measurable in the laboratory), the Lane-Emden equation provides us with a detailed explanation of the astrophysical properties of these stars based on newtonian self-gravitating, spherically symmetric and polytropic fluid. We present a revisited step by step solution for the...
Los nuevos avances tecnológicos en las técnicas de radioterapia [1] han llevado consigo la importancia de la dosimetría 3D [2], debido a esto y para realizar pruebas experimentales iniciales se ha construido un detector electrónico con un arreglo de diodos cubico basado en un concepto de matriz activa [3] [4] para el control de calidad dosimétrico de un acelerador lineal.
El detector...
Objetivo: Utilizar un haz de rayos X kV moderno de calidad para evaluar un tratamiento de radioterapia de dosis baja de fracción única de principios del siglo XX en pacientes con neumonía de acuerdo con las directrices actuales.
Materiales y métodos: Se usó PENELOPE v. 2008 para simular un tratamiento de radioterapia de los años 1920-1940 en ambos pulmones de pacientes con neumonía utilizando...
Gravitoelectromagnetism (GEM) is an approach based on describing gravity in an analogous way to electromagnetism. Vector and tensor formalisms for GEM have been developed in the last years. We will review them by presenting their theoretical background, experimental motivation, and some applications. Recently, this approach has received relevant attention due in part to its analogy to the...
We use Minkowski Functionals (MF) to explore the possible presence of
non-Gaussian signatures in the recently released cosmic microwave background
(CMB) Planck maps. In particular, we investigate MF outcomes for two sets of
simulated CMB maps: one seeded by the $\Lambda$CDM concordance model, another
seeded by the 'best-fit' CMB angular power spectrum. By 'best-fit' we mean
a simulated...
We present a detailed analysis of the thermodynamics of exact asymptotically
flat hairy black holes in Einstein-Maxwell-dilaton theory. We compute the regularized
action, quasilocal stress tensor, and conserved charges by using a ‘counterterm method’
similar to the one extensively used in the AdS-CFT duality. In the presence of a non-trivial
dilaton potential that vanishes at the boundary we...
We report CCD photometric observations of the W UMa-Type eclipsing binary V357 Her gathered during 2017 and 2019 OAUNI campaigns. Good quality light curves using around four thousand individual measurements were constructed and let to verify the orbital period of the system. New own times of minimum light along with previous values from the literature were used to refine the respective...
Classical and quantum mechanical models of a beam splitter are addressed, including the cases where there are one or two input source(s) of light resulting in two consequent output beams. In the classical case we invoke the conservation of energy to derive a $2 \times 2$ matrix $M_{bs}$ which transforms the electric fields. In the quantum mechanical case we invoke conservation of probability...
In this work, we make the first step to derive non-radial pulsation equations in extra dimensions and investigate how the $f$- and $p_1$-mode frequencies of strange quark stars, within the Cowling approximation, change with the number of dimensions. In this regard, the study is performed by solving numerically the non-radial pulsation equations, adjusted for a $d$-dimensional space-time...
We can obtain the cosmic growth rate of structures, $f(z)$, when we compare the gravitational acceleration of a galaxy distribution in the local group with its peculiar velocity measured using the earth relative motion with respect to the Cosmic Background Radiation. The quantity $f(z)$, expected to be $f(z) \approx \Omega_{m}(z)^{\gamma}$ in the $\Lambda$CDM model, can distinguish...
Two-dimensional (2D) atom-thick crystals such as graphene, boron-nitrade (BN), transition metal dichalcogenides (TMDC) and most recently phosphorus allotropes have drawn both experimental and theoretical interest due to their unique electronic and optical properties. For instance, TMDCs possess remarkable properties concerning the tunability of band gap and strong light-matter coupling that...
Presentamos y analizamos las características de transmitancia de sensores de desplazamiento basados en fibras ópticas monomodo afinadas y curvadas en forma de S. Comparamos la sensibilidad del sensor de fibra afinada curvada en S con respecto a la sensibilidad de la fibra afinada sin curvatura previa. Los resultados muestran sensibilidades de hasta 192 pm/µm para los sensores tipo S con...
We investigate a possible inflationary scenario where the expantion is driven by a slow evolution homogeneous single scalar field, whose potential V(φ) is given by a generalized exponential function taken from the κ-deformed theories. Within the slow-roll approximation, we obtained some the main predictions of the model, as scalar spectral index (ns), tensor to scalar ratio (r), number...
Coherent control of single-photon emission, absorption and transport opens promising perspectives for quantum communication and information processing: photons can act as flying quantum bits between distant atomic nodes in a quantum network. A key element of these single-photon networks is the quantum beamsplitter (QBS). The QBS is the most elementary version of a beamsplitter,...
Quantum optics and quantum information have experienced spectacular progress in the past three decades, both theoretically and experimentally.
Quantum information protocols and foundations of quantum mechanics have been tested with correlated photons. Qudit states (d-level quantum systems), a generalization of qubits, are discrete quantum states with dimension d > 2. Entangled qudit states...
A sample of yttrium YFeO3 orthoferrite prepared by the auto-combustion method has been studied. From the hysteresis curve at RT, it was obtained the remanence, coercivity, saturation and antiferromagnetic susceptibility and compared with those obtained with other preparation methods. As a result, these properties have been found to be highly dependent on the method of preparation....
En las últimas dos décadas la técnica de escaneo usando muones cósmicos, o tomografía muónica, ha experimentado un gran desarrollo de aplicaciones en diferentes áreas que requieren el uso de sondas penetrantes no destructivas. Debido a las características de los muones, interación despreciable a través de la fuerza fuerte,baja probabilidad de producir reacciones electromagnéticas que generen...
In the present work we study the secondary cosmic ray flux registered in a water Cherenkov detector (WCD) produced by the interaction of cosmic rays in the atmosphere. The background radiation was characterized in Lima, Peru, at 00 Lat. 00 Long. The detector employed is part of the array of the LAGO collaboration. A secondary trigger is used to filter noise from the electronics in addition to...
Quantum spin Hall phase, or also referred as Topological Insulator state, has been obtained in 2007 in a CdTe/HgTe quantum well [1]. These novel state is possible due to the inverted band order near the Fermi energy. These behaviour is originated because there exist a non negligible correlation between valence electrons of the 5d- and 6s-orbital of Hg [2], and relativistic effects [3],...
El presente trabajo está dedicado al estudio del movimiento de un electrón libre en el seno de un campo electromagnético de un láser intenso, específicamente nos vamos a centrar en el movimiento de electrones cuyas velocidades son cercanas a la velocidad de la luz (velocidades relativistas). Los cálculos de las ecuaciones del movimiento del electrón se realizarán considerando a los electrones...
Soil is the main source of radon and thoron due to the uranium and thorium content [1]. Alpha particles emitted in the decay of these natural radioactive elements produce nuclear reactions in the ground, increasing the levels of ionizing radiation. Therefore, measure of soil radon and thoron concentrations is important. Generally, these measurements are made using active systems compound of an...
During the past three decades, a great deal of attention has been devoted to the synthesis of nanoparticles: many routes have been developed to prepare well-controlled magnetic nanoparticles and the influence of the different chemical parameters has been studied in depth to achieve high reproducibility. It is clear that the size, morphology, chemical composition, structural and physical...
Metallic nanoparticles represent one of the most widely used nanostructures in biomedicine. This is due to the easy modification of its architecture tunable to their electrical properties, which are associated to their surface plasmon resonance (SPR). The SPR localizes the collective oscillation of conduction bands electrons, which when optically excited, generates an amplified electromagnetic...
Understanding distributions of black holes is crucial to both astrophysics and quantum gravity. Studying astrophysical population statistics has even been suggested as a channel to constrain black hole formation from the quantum vacuum. Here we propose a Gedankenexperiment to show that the non-linear properties of binary mergers (simulated with accurate surrogate models) generate an attractor...
The extensions of the Standard Model based on the SU(3)C⊗SU(3)L⊗U(1)X gauge group are known as 331 models. Different properties such as the fermion assignment and the electric charges of the exotic spectrum, which define a particular 331 model, are fixed by a β parameter. In this work, we study the electric charge quantization in two versions of the 331 models, set by the conditions β=1/(33–√)...
Abstract
The abnormal radon exhalation from the earth crust, as a precursory phenomenon related to seismic events, is an important research topic [1, 2]. The radon exhalation is related to the variability of local meteorological parameters. In the present study, a continuous RTM 2200 / SARAD monitor was used to measure the time series of radon concentration in the soil and meteorological...
En lo inconmensurable espacio de nuestro universo se hallan numerosos objetos estelares con características especiales, donde las leyes de la física dejan de tener dominio hasta cierto lindero, asimismo por su grado de complejidad dejan libre el planteamiento de diversos modelos teóricos matemáticos para lograr formular hipótesis sobre evolución espacio temporal del mismo. Los agujeros negros...
La eficiencia del Reactor RP-10 es un factor determinante que contribuye a la fuente de investigación energética y potencial del país; esta eficiencia utiliza ciertos métodos para determinar situaciones de criticidad, distribución de neutrones y determinación de reactividad [1]; estos resultados pueden ser obtenidos mediante vías de cálculo o mediciones experimentales. Dentro del aspecto de...
El presente trabajo presenta la formulación de una ecuación para la creación de quarks pesados obtenidos por la aniquilación de partícula-antipartícula, electrón positrón en hadrones, por maximización de Weizsacker-Williams, método que nos da una aproximación de generación de partículas dentro de una sección eficaz, luego de varios eventos dados por colisiones relativistas de estos leptones....
Las nanopartículas magnéticas utilizadas para el almacenamiento de datos tienden a ser cada vez más pequeñas, con el fin de aumentar la densidad de datos almacenados y reducir el tamaño de los dispositivos[1]. Por lo tanto, estudios de efectos de tamaño finito sobre estas pequeñas nanopartículas es de suma importancia para entender la física que las gobierna. Un enfoque atomístico es el más...
En años recientes las estructuras topológicas han atraído la atención de los investigadores por sus inusuales propiedades y amplia variedad de aplicaciones. En particular las estructuras topológicas en materiales magnéticos son de interés por sus aplicaciones en tecnologías de la información. En el presente trabajo se estudia la emergencia de estructuras topológicas en ferromagnetos y...
Dark matter remains one of the biggest unresolved problems of physics. All we
know is that it doesn’t emit light and almost doesn’t interact with visible matter, except gravitationally. Calculations suggest that it makes up 83% of the matter in the universe.
By developing and implementing a new generation detector: PICO-500, the PICO Collaboration aims to detect and study its properties. But,...
Las películas delgadas tienen un gran número de aplicaciones[1], en particular, películas ferrimagnéticas son de gran interés para el desarrollo de tecnologías de procesamiento y grabación de información[2]. Adicionalmente, este tipo de sistema abre camino para lograr entender el fenómeno conocido como exchange bias[3]. En este estudio modelamos el sistema FeTb/Ta/FeGd, las aleaciones amorfas...
Entropia de Entrelazamiento
Como motivación nos basamos, el problema actual de la paradoja de la información en los agujeros negros, a llevado a buscar nuevas propuestas para la entropía de los agujeros negros, de donde resulta que la entropía de Hawking-Bekenstein esta incompleta, es así que se plantea una entropía "generalizada", que cuenta con un termino extra que considera a los campos...
Scintillators have numerous applications in fundamental research and in for commercial use, including being a common detector for particle physics experiments and the basis for many nuclear medecine instruments. It is a quasi-universal requirement that the light detected in scintillator setups be maximised. Inorganic scintillators will be optimized and characterized by the simulation of...
Resumen– Este trabajo de investigación consiste en medir el voltaje de la carga y descarga de varias baterías de iones de litio y luego analizar los gráficos de voltaje obtenidos. Para ello se elaboró un circuito basado en una placa de Arduino Nano para registrar datos de voltaje de la carga y descarga cada cierto tiempo, este tiempo es programable; el circuito considera un módulo de...
En el presente trabajo, los modelos de radiación solar global basados en las temperaturas extremas diarias para la estimación de valores para la ciudad de Juliaca. Se utilizaron datos de la estación meteorológica DEIVIS de la universidad Nacional de Juliaca y datos obtenidos de la NSRDB (National Solar Radiation Data Base) para los años 2017-2018. Se examinaron cuatro modelos basados en...
We perform a Bayesian model selection analysis for interacting scenarios of dark matter and modified holographic Ricci dark energy (MHRDE) with linear interacting terms.We use a combination of some of the latest cosmological data such as type Ia supernovae, cosmic chronometers, cosmic microwave background and baryon acoustic oscillations measurements. We find strong evidence against all the...
En base a todas las observaciones y estudios por los astrofísicos, sabemos que los Núcleos Galácticos Activos o AGNs son los objetos más luminosos del universo que emiten radiación en casi todo el espectro electromagnético. Estos objetos presentan una estructura muy compleja por lo que estudiar cada una de sus componentes es un gran desafío y de gran aporte para la astrofísica...
The regularized four-dimensional Einstein-Gauss-Bonnet model has been recently proposed in [D. Glavan and C. Lin, Phys. Rev. Lett. \textbf{124}, 081301 (2020)] whose formulation is different of the Einstein theory, allowing us to bypass the Lovelock theorem. The action is formulated in higher dimensions ($D>4$) by adding the Gauss-Bonnet correction to the conventional Einstein-Hilbert action...
Using a Monte Carlo method, the measurement by the double energy technique (2E) of the average prompt neutron multiplicity as a function of the mass of fragments from the thermal neutron-induced fission of 239Pu is simulated. The input data, associated with the masses of complementary primary fragments (A, A'), consist of the yield (Y), the average total kinetic energy ((TKE) ̅) and its...
La busqueda de una nueva Física, como se le llama a las diversas extensiones del Modelo Estandar (ME) de la física de partículas, nos motiva ha extender el grupo de simetría Electro-débil de $SU(2)_{L}\,\otimes\, U(1)_{Y}$ al grupo de gauge con simetría left-right $SU(2)_{L}\,\otimes\,SU(2)_{R}\,\otimes\, U(1)_{B-L}\otimes\mathcal{P}$, donde $\mathcal{P}$ representa una simetría discreta de...
Modifications of the non-linear Schr\"odinger model (MNLS) $ i \partial_{t} \psi(x,t) + \partial^2_{x} \psi(x,t) - [\frac{\delta V}{\delta |\psi|^2} ] \psi(x,t) = 0,$ where $\psi \in C$ and $V: R_{+} \rightarrow R$, are considered. We show that the quasi-integrable MNLS models possess infinite towers of quasi-conservation laws for soliton-type configurations with a special complex conjugation,...
Esta presentación resumirá el trabajo de doctorado de mi estudiante Yin Zhang. Usando una combinación de muchas técnicas experimentales, que incluyen difracción de rayos X (XDR), microscopia electrónica de barrido (SEM), microscopia electrónica de transmisión (TEM), espectroscopia de fotoemisión de rayos X (XPS), espectroscopia de fotoemisión de rayos ultravioleta (UPS), espectroscopia de...
The general objective of the LA-CoNGA-Physics project is to bring the digital transition closer to eight Latin American institutions of higher education in the Andean region (Colombia, Ecuador, Peru and Venezuela) with the support of local and European partners. Thus, our main objective is to offer in 2021 an educational program within the Latin American Alliance in Advanced Physics for...
Due to their interest in both experimental and theoretical study of the structural and electronic properties as multiferroic materials, the compounds YFexCr1-xO3 (x = 0.25, 0.50, 0.75 and 1) were prepared by autocombustion. They were analyzed using techniques that provide information both at the atomic and macroscopic level, including low temperature neutron diffraction, 57Fe Mössbauer...
1) Se propone el trabajo en redes nacionales e internacionales de investigación en Física, reforzando las relaciones de cooperación ya existentes y formando nuevas. La promoción del modelo de trabajo en red se debe reforzar en los términos de las convocatorias a los concursos del CONCYTEC y de otras fuentes de financiamiento. 2) Se propone un modelo de evaluación de la investigación para el...
Quartz tuning fork (QTF) has become an important component in Scanning Probe Microscopy due to its robust and low-energy dissipation characteristics. When the QTF interacts with the sample, the mechanical response of the QTF is typically monitored through its electrical response, which, due to the intrinsic capacitance of the QTF, does not fully reflect the mechanical motion. Herein we report...
El presente trabajo se focalizo en usar los datos de estrellas variables del catálogo OGLE II con la finalidad de separar de ellas un tipo de estrellas variables (las estrellas pulsantes). Las estrellas variables pulsantes son un tipo de estrellas que muestran variación en su luminosidad debido a pulsaciones radiales de su superficie. Su importancia radica en que tienen luminosidades bien...
A low cost method for implementing digital Lock-In Amplification and resonance tracking utilizing a Xilinx Field Programmable Gate Array (FPGA) is presented. Many types of Scanning Probe Microscopy (SPM) employ some form of probe resonance tracking, either for improved sensitivity, or as an additional probing measurement. Implementing these systems digitally through the use of an FPGA affords...
In Shear-force Acoustic Near-field Microscopy, the sensitivity of the acoustic detection system is crucial to reliably characterize the dynamic response of fluids subjected to confinement and shear stress. Herein we report a method to increase the signal-to-noise ratio of the amplification system, as reflected in approach/retraction test undertaken using a SiO2 sample and a silicon pyramid...
Como parte de un plan para medir la seccin transversal total y diferencial del meson charmoso D0, trabajamos con sus dos principales modos de decaimiento. La idea no es medir directamente la seccin transversal absoluta, sino medirlas con respecto a una sección transversal D0, ya medida en este experimento E791. Demostraremos el valor de la técnica de razones de ramificación mostrando datos...
A phenomenological model which has had some success in explaining polarization phenomena and left-right asymmetry in inclusive proton-proton scattering is considered for reactions involving photons. In particular, the reactions (a) g + p -> H + X; (b) g + p() -> p± + X and (c) p() -> + p -> g + X are considered where g = resolved photon and hyperon H = L, S, X etc. Predictions for hyperon...
