Early evolution of disrupted asteroid P/2016 G1 (PANSTARRS)

We present deep imaging observations of activated asteroid P/2016 G1 (PANSTARRS) using the 10.4m Gran Telescopio Canarias (GTC) from late April to early June 2016. The images are best interpreted as the result of a relatively short-duration event with onset about $\mathop{350}_{-30}^{+10}$ days before perihelion (i.e., around 10th February, 2016), starting sharply and decreasing with a $\mathop{24}_{-7}^{+10}$ days (Half-width at half-maximum, HWHM). The results of the modeling imply the emission of $\sim$1.7$\times$10$^7$ kg of dust, if composed of particles of 1 micrometer to 1 cm in radius, distributed following a power-law of index --3, and having a geometric albedo of 0.15. A detailed fitting of a conspicuous westward feature in the head of the comet-like object indicates that a significant fraction of the dust was ejected along a privileged direction right at the beginning of the event, which suggests that the parent body has possibly suffered an impact followed by a partial or total disruption. From the limiting magnitude reachable with the instrumental setup, and assuming a geometric albedo of 0.15 for the parent body, an upper limit for the size of possible fragment debris of $\sim$50 m in radius is derived.Comment: Accepted by ApJ Letter

Naturalness of MSSM dark matter

There exists a vast literature examining the electroweak (EW) fine-tuning problem in supersymmetric scenarios, but little concerned with the dark matter (DM) one, which should be combined with the former. In this paper, we study this problem in an, as much as possible, exhaustive and rigorous way. We have considered the MSSM framework, assuming that the LSP is the lightest neutralino, $\chi_1^0$, and exploring the various possibilities for the mass and composition of $\chi_1^0$, as well as different mechanisms for annihilation of the DM particles in the early Universe (well-tempered neutralinos, funnels and co-annihilation scenarios). We also present a discussion about the statistical meaning of the fine-tuning and how it should be computed for the DM abundance, and combined with the EW fine-tuning. The results are very robust and model-independent and favour some scenarios (like the h-funnel when $M_{\chi_1^0}$ is not too close to $m_h/2$) with respect to others (such as the pure wino case). These features should be taken into account when one explores "natural SUSY" scenarios and their possible signatures at the LHC and in DM detection experiments.Comment: 28 pages, 18 figures. References added, matches JHEP published versio

The Nature of the Gould Belt from a Fractal Analysis of its Stellar Population

The Gould Belt (GB) is a system of gas and young, bright stars distributed along a plane that is inclined with respect to the main plane of the Milky Way. Observational evidence suggests that the GB is our closest star formation complex, but its true nature and origin remain rather controversial. In this work we analyze the fractal structure of the stellar component of the GB. In order to do this, we tailor and apply an algorithm that estimates the fractal dimension in a precise and accurate way, avoiding both boundary and small data set problems. We find that early OB stars (of spectral types earlier than B4) in the GB have a fractal dimension very similar to that of the gas clouds in our Galaxy. On the contrary, stars in the GB of later spectral types show a larger fractal dimension, similar to that found for OB stars of both age groups in the local Galactic disk (LGD). This result seems to indicate that while the younger OB stars in the GB preserve the memory of the spatial structure of the cloud where they were born, older stars are distributed following a similar morphology as that found for the LGD stars. The possible causes for these differences are discussed.Comment: 20 pages including 7 figures and 1 table. ApJ (in press

CCD Strömgren photometry of young reddened clusters

The capabilities of CCD uvby photometry for the study of reddened young clusters are investigated. Observations of four fields in the direction of the clusters Basel 1, Berkeley 86, NGC 6704, and NGC 6756, with a total of 1665 stars measured in at least the y and b bands, produce new estimates for the clusters parameters. The results are compared to those from previously published studies in different photometric systems showing good agreement in the values of color excess and distance modulus, with the exception of NGC 6756, for which an essentially larger distance is found. Furthermore, the ages estimated for this cluster, Basel 1, and NGC 6704 are found to be higher than previously assumed, in particular for the last one. The presence of red giants as cluster members is suggested in Basel 1, NGC 6704, and NGC 6756.Consejería de Educacion y Ciencia Junta de Andalucí

Citril finches during the winter: patterns of distribution, the role of pines and implications for the conservation of the species

El verderón serrano (Serinus citrinella) es una especie paleártica endémica que cría en zonas montañosas subalpinas de la Europa occidental templada. Esta especie parece que está sufriendo un gran declive en su área de distribución septentrional, principalmente en la Selva Negra y en el NE de los Alpes. Se han propuesto muchas razones para dicha disminución, pero todas ellas estaban relacionadas con los hábitats de cría. Dado que esta especie lleva a cabo una migración altitudinal, y que durante el invierno puede utilizar habitats muy distintos, se precisaría un buen conocimiento de los patrones de distribución y de los hábitats utilizados fuera del período reproductor, para poder establecer unas directrices de conservación y gestión adecuadas. Sin embargo, esta información es muy escasa. El propósito de este estudio es determinar el hábitat común utilizado por los verderones serranos en en nordeste de España durante el invierno, para analizar la idoneidad del habitat, y estudiar los movimientos, investigando el origen de la aves que invernan en Cataluña. La distribución se modelizó utilizando el análisis discriminante y la modelización de entropía máxima con los datos registrados desde 1972 al 2009 sobre la presencia de esta especie durante el invierno en Cataluña. Los resultados evidenciaron que la presencia de bosques abiertos mixtos de pino negral (Pinus nigra subsp. salzmanii) y pino silvestre o albar (Pinus sylvestris), con numerosas tierras de cultivo y plantas arvenses, en areas submediterráneas típicas en las que las temperaturas templadas de finales de invierno (días soleados) facilitan la apertura de las piñas, fueron las variables ecológicas y bioclimáticas claves responsables de la distribución del verderón serrano en invierno (valores AUC o área bajo la curva: datos de entrenamiento AUC = 0,955; datos del test AUC = 0,953). Analizamos las recuperaciones (N = 238) de 2.368 aves anilladas en las áreas de invernada y 12.648 aves anilladas en localizaciones subalpinas en los Pirineos adyacentes, desde 1977 al 2004. Los resultados de los datos de recuperación de anillas muestran que en el área de estudio se capturaron aves procedentes de muy diversas localizaciones dentro del área de distribución de la especie estudiada, incluyendo aves transpirenaicas procedentes de los Alpes. Ello enfatiza la gran movilidad de las poblaciones del verderón serrano hasta alcanzar las áreas de invernada. Desde el punto de vista de la conservación, la gran importancia de los pinos (principalmente del negral) para la distribución invernal de esta especie pone de manifiesto que cualquier amenaza para los pinos, especialmente los incendios forestales, tendrá grandes efectos adversos sobre las poblaciones del verderón serrano. Palabras clave: Verderón serrano, Invernada, Selección del hábitat, Idoneidad del hábitat, Desplazamientos, Conservación, Pino negral, Pino silvestre, Pino albar.El verderón serrano (Serinus citrinella) es una especie paleártica endémica que cría en zonas montañosas subalpinas de la Europa occidental templada. Esta especie parece que está sufriendo un gran declive en su área de distribución septentrional, principalmente en la Selva Negra y en el NE de los Alpes. Se han propuesto muchas razones para dicha disminución, pero todas ellas estaban relacionadas con los hábitats de cría. Dado que esta especie lleva a cabo una migración altitudinal, y que durante el invierno puede utilizar habitats muy distintos, se precisaría un buen conocimiento de los patrones de distribución y de los hábitats utilizados fuera del período reproductor, para poder establecer unas directrices de conservación y gestión adecuadas. Sin embargo, esta información es muy escasa. El propósito de este estudio es determinar el hábitat común utilizado por los verderones serranos en en nordeste de España durante el invierno, para analizar la idoneidad del habitat, y estudiar los movimientos, investigando el origen de la aves que invernan en Cataluña. La distribución se modelizó utilizando el análisis discriminante y la modelización de entropía máxima con los datos registrados desde 1972 al 2009 sobre la presencia de esta especie durante el invierno en Cataluña. Los resultados evidenciaron que la presencia de bosques abiertos mixtos de pino negral (Pinus nigra subsp. salzmanii) y pino silvestre o albar (Pinus sylvestris), con numerosas tierras de cultivo y plantas arvenses, en areas submediterráneas típicas en las que las temperaturas templadas de finales de invierno (días soleados) facilitan la apertura de las piñas, fueron las variables ecológicas y bioclimáticas claves responsables de la distribución del verderón serrano en invierno (valores AUC o área bajo la curva: datos de entrenamiento AUC = 0,955; datos del test AUC = 0,953). Analizamos las recuperaciones (N = 238) de 2.368 aves anilladas en las áreas de invernada y 12.648 aves anilladas en localizaciones subalpinas en los Pirineos adyacentes, desde 1977 al 2004. Los resultados de los datos de recuperación de anillas muestran que en el área de estudio se capturaron aves procedentes de muy diversas localizaciones dentro del área de distribución de la especie estudiada, incluyendo aves transpirenaicas procedentes de los Alpes. Ello enfatiza la gran movilidad de las poblaciones del verderón serrano hasta alcanzar las áreas de invernada. Desde el punto de vista de la conservación, la gran importancia de los pinos (principalmente del negral) para la distribución invernal de esta especie pone de manifiesto que cualquier amenaza para los pinos, especialmente los incendios forestales, tendrá grandes efectos adversos sobre las poblaciones del verderón serrano. Palabras clave: Verderón serrano, Invernada, Selección del hábitat, Idoneidad del hábitat, Desplazamientos, Conservación, Pino negral, Pino silvestre, Pino albar.The Citril finch Serinus citrinella is a Paleartic endemic species that breeds in the subalpine mountain zones of western temperate Europe. The species seems to be suffering a serious decline in its northern range, mainly in the Black Forest and the NE of the Alps. Numerous reasons have been provided for this decline, but all of them have been related to breeding habitats. Given that the species undergoes an altitudinal migration and that during winter it may use very different habitats, a sound knowledge of the distribution patterns and habitats used outside the breeding period is needed to conduct adequate conservation policies and management. This information, however, is largely lacking. The aim of this paper was to determine the current habitat used by Citril finches in north–eastern Spain during the winter, to analyse habitat suitability and to study movements, by investigating the origin of birds that overwinter in Catalonia. Citril finch distribution was modelled using both discriminant analysis and maximum entropy modelling, on the basis of species occurrences during winter in Catalonia (data from 1972–2009). Results showed that the presence of two tree species, Black pine (Pinus nigra subsp. salzmanii) and Scots pine (Pinus sylvestris), both as part of mixed open forests, and the presence of abundant farmland and arvensic plants —the two vegetation units located in a typical sub¬mediterranean context, where the warm temperatures (sunny days) in late winter permit the cones to open—, were the ecological and bioclimatic variables that explain the distribution model. All these variables in tandem seem to be the key for the current potential distribution of the Citril finch in winter (AUCscores: training data AUC= 0.955; test data AUC = 0.953). We analyzed recoveries (N = 238) of 2,368birds ringed at wintering grounds and 12,648 birds ringed at subalpine localities in the adjacent Pyrenees from 1977–2004. We found that in the study area, we recovered ringed birds from many different locations from across the distributional range of the species, including trans–Pyrenean birds from the Alps. This stresses the high mobility of Citril finch populations to reach wintering areas. From a conservation point of view, the high importance of pines (mainly Black pine) for the wintering distribution of the species stresses that any threat on pines, especially forest fires, will have acute detrimental effects for Citril finch populations. Key words: Citril finch, Wintering, Habitat selection, Habitat suitability, Movements, Conservation, Black pine, Scots pine

Rapid Orbital Decay in the 12.75-Minute Binary White Dwarf J0651+2844

We report the detection of orbital decay in the 12.75-minute, detached binary white dwarf (WD) SDSS J065133.338+284423.37 (hereafter J0651). Our photometric observations over a 13 month baseline constrain the orbital period to 765.206543(55) s and indicate that the orbit is decreasing at a rate of (-9.8 +/- 2.8) x 10(-12) s s(-1) (or -0.31 +/- 0.09 ms yr(-1)). We revise the system parameters based on our new photometric and spectroscopic observations: J0651 contains two WDs with M-1 = 0.26 +/- 0.04 M-circle dot and M-2 = 0.50 +/- 0.04 M-circle dot. General relativity predicts orbital decay due to gravitational wave radiation of (-8.2 +/- 1.7) x 10(-12) s s(-1) (or -0.26 +/- 0.05 ms yr(-1)). Our observed rate of orbital decay is consistent with this expectation. J0651 is currently the second-loudest gravitational wave source known in the milli-Hertz range and the loudest non-interacting binary, which makes it an excellent verification source for future missions aimed at directly detecting gravitational waves. Our work establishes the feasibility of monitoring this system's orbital period decay at optical wavelengths.NSF AST-0909107, AST-1008734Norman Hackerman Advanced Research Program 003658-0252-2009Astronom

El verderón serrano en invierno: patrones de distribución, el papel de los pinos e implicaciones para la conservación de la especie

The Citril finch Serinus citrinella is a Paleartic endemic species that breeds in the subalpine mountain zones of western temperate Europe. The species seems to be suffering a serious decline in its northern range, mainly in the Black Forest and the NE of the Alps. Numerous reasons have been provided for this decline, but all of them have been related to breeding habitats. Given that the species undergoes an altitudinal migration and that during winter it may use very different habitats, a sound knowledge of the distribution patterns and habitats used outside the breeding period is needed to conduct adequate conservation policies and management. This information, however, is largely lacking. The aim of this paper was to determine the current habitat used by Citril finches in north–eastern Spain during the winter, to analyse habitat suitability and to study movements, by investigating the origin of birds that overwinter in Catalonia. Citril finch distribution was modelled using both discriminant analysis and maximum entropy modelling, on the basis of species occurrences during winter in Catalonia (data from 1972–2009).El verderón serrano (Serinus citrinella) es una especie paleártica endémica que cría en zonas montañosas subalpinas de la Europa occidental templada. Esta especie parece que está sufriendo un gran declive en su área de distribución septentrional, principalmente en la Selva Negra y en el NE de los Alpes. Se han propuesto muchas razones para dicha disminución, pero todas ellas estaban relacionadas con los hábitats de cría. Dado que esta especie lleva a cabo una migración altitudinal, y que durante el invierno puede utilizar habitats muy distintos, se precisaría un buen conocimiento de los patrones de distribución y de los hábitats utilizados fuera del período reproductor, para poder establecer unas directrices de conservación y gestión adecuadas. Sin embargo, esta información es muy escasa. El propósito de este estudio es determinar el hábitat común utilizado por los verderones serranos en en nordeste de España durante el invierno, para analizar la idoneidad del habitat, y estudiar los movimientos, investigando el origen de la aves que invernan en Cataluña. La distribución se modelizó utilizando el análisis discriminante y la modelización de entropía máxima con los datos registrados desde 1972 al 2009 sobre la presencia de esta especie durante el invierno en Cataluña. Los resultados evidenciaron que la presencia de bosques abiertos mixtos de pino negral (Pinus nigra subsp. salzmanii) y pino silvestre o albar (Pinus sylvestris), con numerosas tierras de cultivo y plantas arvenses, en areas submediterráneas típicas en las que las temperaturas templadas de finales de invierno (días soleados) facilitan la apertura de las piñas, fueron las variables ecológicas y bioclimáticas claves responsables de la distribución del verderón serrano en invierno (valores AUC o área bajo la curva: datos de entrenamiento AUC = 0,955; datos del test AUC = 0,953). Analizamos las recuperaciones (N = 238) de 2.368 aves anilladas en las áreas de invernada y 12.648 aves anilladas en localizaciones subalpinas en los Pirineos adyacentes, desde 1977 al 2004. Los resultados de los datos de recuperación de anillas muestran que en el área de estudio se capturaron aves procedentes de muy diversas localizaciones dentro del área de distribución de la especie estudiada, incluyendo aves transpirenaicas procedentes de los Alpes. Ello enfatiza la gran movilidad de las poblaciones del verderón serrano hasta alcanzar las áreas de invernada. Desde el punto de vista de la conservación, la gran importancia de los pinos (principalmente del negral) para la distribución invernal de esta especie pone de manifiesto que cualquier amenaza para los pinos, especialmente los incendios forestales, tendrá grandes efectos adversos sobre las poblaciones del verderón serrano.This work was supported by grants from the Ministerio de Ciencia e Innovación (CGL 2009–10652)

Minimization of measuring points for the electric field exposure map generation in indoor environments by means of Kriging interpolation and selective sampling

In a world with increasing systems accessing to radio spectrum, the concern for exposure to electromagnetic fields is growing and therefore it is necessary to check limits in those areas where electromagnetic sources are working. Therefore, radio and exposure maps are continuously being generated, mainly in outdoor areas, by using many interpolation techniques. In this work, Surfer software and Kriging interpolation have been used for the first time to generate an indoor exposure map. A regular measuring mesh has been generated. Elimination of Less Significant Points (ELSP) and Geometrical Elimination of Neighbors (GEN) strategies to reduce the measuring points have been presented and evaluated. Both strategies have been compared to the map generated with all the measurements by calculating the root mean square and mean absolute errors. Results indicate that ELSP method can reduce up to 70% of the mesh measuring points while producing similar exposure maps to the one generated with all the measuring points. GEN, however, produces distorted maps and much higher error indicators even for 50% of eliminated measuring points. As a conclusion, a procedure for reducing the measuring points to generate radio and exposure maps is proposed based on the ELSP method and the Kriging interpolation.This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors

Blockchain-Based Services Implemented in a Microservices Architecture Using a Trusted Platform Module Applied to Electric Vehicle Charging Stations

Microservice architectures exploit container-based virtualized services, which rarely use hardware-based cryptography. A trusted platform module (TPM) offers a hardware root for trust in services that makes use of cryptographic operations. The virtualization of this hardware module offers high usability for other types of service that require TPM functionalities. This paper proposes the design of TPM virtualization in a container. To ensure integrity, different mechanisms, such as attestation and sealing, have been developed for the binaries and libraries stored in the container volumes. Through a REST API, the container offers the functionalities of a TPM, such as key generation and signing. To prevent unauthorized access to the container, this article proposes an authentication mechanism based on tokens issued by the Cognito Amazon Web Service. As a proof of concept and applicability in industry, a use case for electric vehicle charging stations using a microservice-based architecture is proposed. Using the EOS.IO blockchain to maintain a copy of the data, the virtualized TPM microservice provides the cryptographic operations necessary for blockchain transactions. Through a two-factor authentication mechanism, users can access the data. This scenario shows the potential of using blockchain technologies in microservice-based architectures, where microservices such as the virtualized TPM fill a security gap in these architectures.Infineon TechnologiesProgram “Digitalisierung der EnergiewendeBundesministeriums für Wirtschaft und EnergieTrusted Blockchains fur das offene, intelligente Energienetz der Zukunft (tbiEnergy)FKZ 03EI6029DEuropean Health and Digital Executive Agency (HaDEA) program under Grant Agreement No 101092950 (EDGELESS project)FEDER/Junta de Andalucia-Consejeria de Transformacion Economica, Industria, Conocimiento y Universidades under Project B-TIC-588-UGR20

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Taha Toros Arşivi, Dosya No: 95-Fakir BaykurtUnutma İstanbul projesi İstanbul Kalkınma Ajansı'nın 2016 yılı "Yenilikçi ve Yaratıcı İstanbul Mali Destek Programı" kapsamında desteklenmiştir. Proje No: TR10/16/YNY/010