A refined analysis of the low-mass eclipsing binary system T-Cyg1-12664

The observational mass-radius relation of main sequence stars with masses between ~0.3 and 1.0 Msun reveals deviations between the stellar radii predicted by models and the observed radii of stars in detached binaries. We generate an accurate physical model of the low-mass eclipsing binary T-Cyg1-12664 in the Kepler mission field to measure the physical parameters of its components and to compare them with the prediction of theoretical stellar evolution models. We analyze the Kepler mission light curve of T-Cyg1-12664 to accurately measure the times and phases of the primary and secondary eclipse. In addition, we measure the rotational period of the primary component by analyzing the out-of-eclipse oscillations that are due to spots. We accurately constrain the effective temperature of the system using ground-based absolute photometry in B, V, Rc, and Ic. We also obtain and analyze V, Rc, Ic differential light curves to measure the eccentricity and the orbital inclination of the system, and a precise Teff ratio. From the joint analysis of new radial velocities and those in the literature we measure the individual masses of the stars. Finally, we use the PHOEBE code to generate a physical model of the system. T-Cyg1-12664 is a low eccentricity system, located d=360+/-22 pc away from us, with an orbital period of P=4.1287955(4) days, and an orbital inclination i=86.969+/-0.056 degrees. It is composed of two very different stars with an active G6 primary with Teff1=5560+/-160 K, M1=0.680+/-0.045 Msun, R1=0.799+/-0.017 Rsun, and a M3V secondary star with Teff2=3460+/-210 K, M2=0.376+/-0.017 Msun, and R2=0.3475+/-0.0081 Rsun. The primary star is an oversized and spotted active star, hotter than the stars in its mass range. The secondary is a cool star near the mass boundary for fully convective stars (M~0.35 Msun), whose parameters appear to be in agreement with low-mass stellar model.Comment: 18 pages, 15 figures, 15 table

Gaussian tripartite entanglement in the simultaneous measurement of position and momentum

In this work, we prove the generation of genuine tripartite continuous-variable entanglement in the unitary dynamics of the simultaneous measurement process of position and momentum observables raised by Arthurs and Kelly, considering a measurement configuration where the system under examination is a rotated, displaced, and squeezed vacuum state. Under these assumptions, the measurement configuration is entirely described by a Gaussian state. Then, through the positive partial transpose criterion (PPT), we certify genuine tripartite entanglement by testing the non-separability of the three $\left(1~ \text{vs}~2\right)$-mode bipartitions of the system. This process allows us to classify the qualitative properties of the entanglement in the category of fully inseparable Gaussian states according to the classification exposed in [Giedke et al., \href{https://link.aps.org/doi/10.1103/PhysRevA.64.052303}{Phys. Rev. A \textbf{64}, 052303 (2001)}]. Besides, we determine the quantitative entanglement properties of the system using the residual tripartite R{\'e}nyi-2 entanglement as a quantifier measure.Comment: 15 pages, 8 figure

Influencia del café, té y vino tinto en la recidiva del color en piezas tratadas con clareamiento

68 P.En este estudio, in vitro, determinamos si los dientes tratados con clareamiento presentan un mayor cambio de color en el tiempo que los no tratados, al ser sometidos a tinción con tres bebidas cromógenas que corresponden a café, té y vino. Para lograrlo, se utilizaron 45 incisivos sanos de bovino, en probetas acrílicas, conservados en suero a 37ºC. Cada espécimen se dividió en dos mitades, una sometida a clareamiento con peróxido de hidrógeno al 35% y la otra como control. Se midió el color con el Espectrofotómetro Vita EasyShade, antes y después del clareamiento. Se dividieron los especímenes al azar en tres grupos de 15 y fueron sumergidos completamente en café, té y vino, durante 10 minutos, 20 veces, registrando el color después de cada inmersión. Los datos fueron analizados con ANOVA y Test de Tukey, con 95% de intervalo de confianza.Los resultados obtenidos mostraron que, el clareamiento modifica significativamente (p=0.05) el color en los tres grupos (GC=85.8 a 95.1; GT=87.4 a 97.3 y GV=90.8 a 99.3). La recidiva de color en los tres grupos se observa a lo largo de las 20 inmersiones, siendo significativa la diferencia de valores ΔE iniciales (GC=18.89; GT=22.97; GV=56.46) y finales (GC=5.56; GT=5.38; GV=12.49). El grupo tratado presenta mayor descenso de unidades ΔE a lo largo de las inmersiones, por lo que es el grupo más teñido (GCcontrol=20.98-5.01; GTcontrol=17.11-3.66; GVcontrol=54.62-11.49). Las tres bebidas cromógenas causan recidiva de color en los dientes clareados, siendo el vino el cromógeno que causa mayor tinción, por ser el que pierde más unidades ΔE entre inmersiones. Se concluyo que las piezas tratadas con clareamiento, sometidas a los tres tipos de cromógenos y a diferentes tiempos de inmersión, tienen mayor cambio de color que las que no son sometidas al tratamiento. Palabras clave: Clareamiento, bebidas cromógenas, recidiva de color./ABSTRACT:The aim of this in vitro study is to establish if teeth treated with dental bleaching have higher change of color in time than those that are not treated, when subjected to three chromogenic beverages (coffee, tea and red wine). There were used 45 healthy bovine incisors, which were placed on acrylic and maintain in 0.9% sodium chloride, at 37ºC. Every specimen was divided into 2 half; one half was subjected to dental bleaching with 35% hydrogen peroxide and the other was taken as control. The initial color was measured with the Vita EasyShade Spectrophotometer, before and after bleaching.The specimens were divided randomly into 3 groups of 15, and were immerse in coffee (GC), tea (GT) and red wine (GV) for 10 minutes, 20 times, recording the value after each immersion. The data was analyzed with Anova and Tukey test.The results show that bleaching significantly modify (p=0.05) color in the three groups (GC=85.8 to 95.1; GT=87.4 to 97.3 y GV=90.8 to 99.3). Color relapse in the three groups was observed along the 20 immersions. Initial ΔE values (GC=18.89; GT=22.97; GV=56.46) were significantly different than final ΔE values (GC=5.56; GT=5.38; GV=12.49). After the 20 immersions, the chromogenic beverages stained more the treated group because a higher ΔE units decrease was observed in this group (GCcontrol=20.98-5.01; GTcontrol=17.11-3.66; GVcontrol=54.62-11.49). The three chromogenic beverages produced color relapse in the bleaching teeth, being red wine the one that causes more staining showing higher decrease in ΔE units between immersions. It was concluded that the specimes treated with dental bleaching subjected to three kinds of chromogenic beverages in different immersions time, had higher change of color than the control group.Keywords: dental bleaching, chromogenic beverages, color relaps