605 research outputs found

    High-precision analysis of binary stars with planets. I. Searching for condensation temperature trends in the HD 106515 system

    Full text link
    We explore the probable chemical signature of planet formation in the remarkable binary system HD 106515. The A star hosts a massive long-period planet with 9 MJup detected by radial velocity. We also refine stellar and planetary parameters by using non-solar-scaled opacities when modeling the stars. Methods. We carried out a simultaneous determination of stellar parameters and abundances, by applying for the first time non-solar-scaled opacities in this binary system, in order to reach the highest possible precision. Results. The stars A and B in the binary system HD 106515 do not seem to be depleted in refractory elements, which is different when comparing the Sun with solar-twins. Then, the terrestrial planet formation would have been less efficient in the stars of this binary system. Together with HD 80606/7, this is the second binary system which does not seem to present a (terrestrial) signature of planet formation, and hosting both systems an eccentric giant planet. This is in agreement with numerical simulations, where the early dynamical evolution of eccentric giant planets clear out most of the possible terrestrial planets in the inner zone. We refined the stellar mass, radius and age for both stars and found a notable difference of 78% in R compared to previous works. We also refined the planet mass to mp sini = 9.08 +/- 0.20 MJup, which differs by 6% compared with literature. In addition, we showed that the non-solar-scaled solution is not compatible with the classical solar-scaled method, and some abundance differences are comparable to NLTE or GCE effects specially when using the Sun as reference. Then, we encourage the use of non-solar-scaled opacities in high-precision studies such as the detection of Tc trends.[abridged]Comment: 9 pages, 10 figures, A&A accepted. arXiv admin note: text overlap with arXiv:1507.0812

    Hasta que naturalmente muera: ejecución pública en Chile colonial (1700-1810)

    Get PDF
    Son escasas las referencias sobre la práctica de la ejecución en el pasado colonial chileno,[1] sobre todo en lo que concierne a la participación y al comportamiento de la gente enfrentada al ceremonial del patíbulo

    ¿Veis aquí el Potro del tormento? ¡Decid la verdad! Tortura judicial en la Real Audiencia de Santiago de Chile

    Get PDF
    La tortura ha estado presente a largo de los siglos, tanto dentro como fuera de la ley. Durante el siglo XX esta realidad se nos ha presentado particularmente evidente y cruda en el acontecer mundial y nacional. La amplitud de este hecho nos ha llevado a preguntarnos por su ejercicio durante el período colonial en Chile, tema del cual daremos ciertas impresiones respecto de su práctica judicial. Ese tipo de tortura, llamada también cuestión de tormento, se define como «una prueba en el proceso penal, la cual era subsidiaria y reiterable, y estaba destinada a provocar por medios violentos la confesión de culpabilidad de aquel contra quien hubiera ciertos indicios; o dirigida a veces, a obtener la acusación del reo contra sus cómplices, o también a forzar las declaraciones de los testigos».[1] Para tratar lo anterior nos hemos basado en el material encontrado tras la revisión de juicios por homicidio contenidos en el archivo de la Real Audiencia de Santiago. El período estudiado va desde el siglo XVII hasta la primera década del XIX

    Fundamentos y proyecciones de la teoría de la ley natural contemporánea

    Get PDF
    In this paper I will make a review of the core elements of the recent natural law ethical theories in analytic philosophy. I will expose the elements they share, and then its more essential differences, especially those related to epistemology and metaphysics. Finally, I shall explore the possibilities of development for natural law theories, and its metaethical implications, especially those related to a metaphysical and epistemological grounding for natural law.En este artículo se hará una revisión de los aspectos más destacados de las teorías éticas iusnaturalistas recientes en la tradición analítica. Se expondrán los aspectos unitarios de dichas teorías y, posteriormente, se analizarán sus divergencias más esenciales, específicamente, las epistemológicas y ontológicas. Finalmente, se explorarán las posibilidades de desarrollo para las teorías iusnaturalistas y sus implicancias metaéticas, especialmente las relativas a la fundamentación metafísica y epistemológica de la ley natural

    Empirical instability strip for classical Cepheids: I. The LMC galaxy

    Full text link
    The instability strip (IS) of classical Cepheids has been extensively studied theoretically. Comparison of the theoretical IS edges with those obtained empirically, using the most recent Cepheids catalogs available, can provide us with insights into the physical processes that determine the position of the IS boundaries. In this study, we investigate the empirical positions of the IS of the classical Cepheids in the Large Magellanic Cloud (LMC), considering any effect that increases its width, to obtain intrinsic edges that can be compared with theoretical models. We use data of classical fundamental-mode (F) and first-overtone (1O) LMC Cepheids from the OGLE-IV variable star catalog, together with a recent high-resolution reddening map from the literature. Our final sample includes 2058 F and 1387 1O Cepheids. We studied their position on the Hertzsprung-Russell diagram and determined the IS borders by tracing the edges of the color distribution along the strip. We obtain the blue and red edges of the IS in V- and I-photometric bands, in addition to logTeff\log T_{\rm eff} and logL\log L. The results obtained show a break located at the Cepheids' period of about 3 days, which was not reported before. We compare our empirical borders with theoretical ones published in the literature obtaining a good agreement for specific parameter sets. The break in the IS borders is most likely explained by the depopulation of second and third crossing classical Cepheids in the faint part of the IS, since blue loops of evolutionary tracks in this mass range do not extend blueward enough to cross the IS at the LMC metallicity. Results from the comparison of our empirical borders with theoretical ones prove that our empirical IS is a useful tool for constraining theoretical models.Comment: 10 pages, 13 figures, accepted for publication in Astronomy & Astrophysic

    The ALMA Frontier Fields Survey - IV. Lensing-corrected 1.1 mm number counts in Abell 2744, MACSJ0416.1-2403 and MACSJ1149.5+2223

    Get PDF
    [abridged] Characterizing the number counts of faint, dusty star-forming galaxies is currently a challenge even for deep, high-resolution observations in the FIR-to-mm regime. They are predicted to account for approximately half of the total extragalactic background light at those wavelengths. Searching for dusty star-forming galaxies behind massive galaxy clusters benefits from strong lensing, enhancing their measured emission while increasing spatial resolution. Derived number counts depend, however, on mass reconstruction models that properly constrain these clusters. We estimate the 1.1 mm number counts along the line of sight of three galaxy clusters, i.e. Abell 2744, MACSJ0416.1-2403 and MACSJ1149.5+2223, which are part of the ALMA Frontier Fields Survey. We perform detailed simulations to correct these counts for lensing effects. We use several publicly available lensing models for the galaxy clusters to derive the intrinsic flux densities of our sources. We perform Monte Carlo simulations of the number counts for a detailed treatment of the uncertainties in the magnifications and adopted source redshifts. We find an overall agreement among the number counts derived for the different lens models, despite their systematic variations regarding source magnifications and effective areas. Our number counts span ~2.5 dex in demagnified flux density, from several mJy down to tens of uJy. Our number counts are consistent with recent estimates from deep ALMA observations at a 3σ\sigma level. Below \approx 0.1 mJy, however, our cumulative counts are lower by \approx 1 dex, suggesting a flattening in the number counts. In our deepest ALMA mosaic, we estimate number counts for intrinsic flux densities \approx 4 times fainter than the rms level. This highlights the potential of probing the sub-10 uJy population in larger samples of galaxy cluster fields with deeper ALMA observations.Comment: 19 pages, 14 figures, 3 tables. Accepted for publication in A&

    Musical preferences and technologies: Contemporary material and symbolic distinctions criticised

    Get PDF
    Today how individuals interact with various cultural items is not perfectly consistent with theoretical frameworks of influential scholars on cultural consumption, such as Bourdieu (1984), Gans (1999), and Peterson and Simkus (1992). One such variation is in the ever increasing variety of technological modes to acquire and listen to music (Pinch and Bijsterveld, 2004). However, as a consequence of digital divides (van Dijk, 2006), technological items may not be distributed equally among social groups. At present, the value of status-making through a preference for different genres of music extends itself to different forms of consumption and ways of experiencing music. We are yet to fully understand the power these practices have on generating status. This article is therefore motivated by the need to integrate within quantitative frameworks of taste and cultural consumption, an analysis of individuals’ technological engagement. These two dimensions, integrated as components of musical practices, enhance our understanding of cultural boundaries across different social groups.The objective is to bridge a gap detected in the literature, addressing the following questions: Are technological modes to listen to music related to musical tastes

    ζ1 + ζ2 Reticuli binary system: a puzzling chromospheric activity pattern

    Get PDF
    We perform, for the first time, a detailed long-term activity study of the binary system ζ Ret. We use all available HARPS spectra obtained between the years 2003 and 2016. We build a time series of the Mount Wilson S index for both stars, then we analyse these series by using Lomb-Scargle periodograms. The components ζ1 Ret and ζ2 Ret that belong to this binary system are physically very similar to each other and also similar to our Sun, which makes it a remarkable system. We detect in the solar-analogue star ζ2 Ret a long-term activity cycle with a period of ?10 yr, similar to the solar one (?11 yr). It is worthwhile to mention that this object satisfies previous criteria for a flat star and for a cycling star simultaneously. Another interesting feature of this binary system is a high ?0.220 dex difference between the average log (R^´ }_HK) activity levels of both stars. Our study clearly shows that ζ1 Ret is significantly more active than ζ2 Ret. In addition, ζ1 Ret shows an erratic variability in its stellar activity. In this work, we explore different scenarios trying to explain this rare behaviour in a pair of coeval stars, which could help to explain the difference in this and other binary systems. From these results, we also warn that for the development of activity-age calibrations (which commonly use binary systems and/or stellar clusters as calibrators) the whole history of activity available for the stars involved should be taken into account.Fil: Flores, M. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Universidad Nacional de San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio; ArgentinaFil: Saffe, Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Universidad Nacional de San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio; ArgentinaFil: Buccino, Andrea Paola. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Jaque Arancibia, Marcelo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Universidad Nacional de San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio; ArgentinaFil: González, J F. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Universidad Nacional de San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio; ArgentinaFil: Nuñez, N E. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Universidad Nacional de San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio; ArgentinaFil: Jofré, E. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba; Argentin

    KELT-17: a chemically peculiar Am star and a hot-Jupiter planet

    Full text link
    Context. The detection of planets orbiting chemically peculiar stars is very scarcely known in the literature. Aims. To determine the detailed chemical composition of the remarkable planet host star KELT-17. This object hosts a hot-Jupiter planet with 1.31 MJup detected by transits, being one of the more massive and rapidly rotating planet hosts to date. We aimed to derive a complete chemical pattern for this star, in order to compare it with those of chemically peculiar stars. Methods. We carried out a detailed abundance determination in the planet host star KELT-17 via spectral synthesis. Stellar parameters were estimated iteratively by fitting Balmer line profiles and imposing the Fe ionization balance, using the program SYNTHE together with plane-parallel ATLAS12 model atmospheres. Specific opacities for an arbitrary composition and microturbulence velocity vmicro were calculated through the Opacity Sampling (OS) method. The abundances were determined iteratively by fitting synthetic spectra to metallic lines of 16 different chemical species using the program SYNTHE. The complete chemical pattern of KELT-17 was compared to the recently published average pattern of Am stars. We estimated the stellar radius by two methods: a) comparing the synthetic spectral energy distribution with the available photometric data and the Gaia parallax, and b) using a Bayesian estimation of stellar parameters using stellar isochrones. Results. We found overabundances of Ti, Cr, Mn, Fe, Ni, Zn, Sr, Y, Zr, and Ba, together with subsolar values of Ca and Sc. Notably, the chemical pattern agrees with those recently published of Am stars, being then KELT-17 the first exoplanet host whose complete chemical pattern is unambiguously identified with this class. The stellar radius derived by two different methods agrees to each other and with those previously obtained in the literature.Comment: 5 pages, 8 figures, 2 tables, A&A accepte
    corecore