7 research outputs found
Fundamental properties of the pre-main sequence eclipsing stars of MML 53 and the mass of the tertiary
We present the most comprehensive analysis to date of the Upper Centaurus Lupus eclipsing binary MML 53 (with PEBâ=â2.097892 d), and for the first time, confirm the bound-nature of the third star (in a P3ââŒâ9 yr orbit) by constraining its mass dynamically. Our analysis is based on new and archival spectra and time-series photometry, spanning 80% of one orbit of the outer component. From the spectroscopic analysis, we determined the temperature of the primary star to be 4880 ± 100 K. The study of the close binary incorporated treatment of spots and dilution by the tertiary in the light curves, allowing for the robust measurement of the masses of the eclipsing components within 1% (M1â=â1.0400â
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0.0067 Mâ and M2â=â0.8907â
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0.0058 Mâ), their radii within 4.5% (R1â=â1.283â
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0.043 Râ and R2â=â1.107â
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0.049 Râ), and the temperature of the secondary star (Teff,â2 = 4379 ± 100 K). From the analysis of the eclipse timings, and the change in systemic velocity of the eclipsing binary and the radial velocities of the third star, we measured the mass of the outer companion to be 0.7 Mâ (with a 20% uncertainty). The age we derived from the evolution of the temperature ratio between the eclipsing components is fully consistent with previous, independent estimates of the age of Upper Centaurus Lupus (16 ± 2 Myr). At this age, the tightening of the MML 53 eclipsing binary has already occurred, thus supporting close-binary formation mechanisms that act early in the starsâ evolution. The eclipsing components of MML 53 roughly follow the same theoretical isochrone, but appear to be inflated in radius (by 20% for the primary and 10% for the secondary) with respect to recent evolutionary models. However, our radius measurement of the 1.04 Mâ primary star of MML 53 is in full agreement with the independent measurement of the secondary of NP Per which has the same mass and a similar age. The eclipsing stars of MML 53 are found to be larger but not cooler than predicted by non-magnetic models, it is not clear what is the mechanism that is causing the radius inflation given that activity, spots and/or magnetic fields slowing their contraction, require the inflated stars to be cooler to remain in thermal equilibrium
EELT-HIRES the high-resolution spectrograph for the E-ELT
The first generation of E-ELT instruments will include an optic-infrared High Resolution Spectrograph, conventionally indicated as EELT-HIRES, which will be capable of providing unique breakthroughs in the fields of exoplanets, star and planet formation, physics and evolution of stars and galaxies, cosmology and fundamental physics. A 2-year long phase A study for EELT-HIRES has just started and will be performed by a consortium composed of institutes and organisations from Brazil, Chile, Denmark, France, Germany, Italy, Poland, Portugal, Spain, Sweden, Switzerland and United Kingdom. In this paper we describe the science goals and the preliminary technical concept for EELT-HIRES which will be developed during the phase A, as well as its planned development and consortium organisation during the study.This work was supported from the Italian National Institute for Astrophysics (Istituto Nazionale Italiano di Astrofisica, INAF). RM , DB, CH, MF, XS, DQ and MGH acknowledge support from the UK Science and Technology Facilities Council (STFC). MGH is supported by the ERC Advanced grant Emergence-32056. This work was supported by Fundaçao para a CiĂȘncia e a Tecnologia (FCT, Portugal), project ref. PTDC/FIS-AST/1526/2014, through national funds and by FEDER through COMPETE2020 (ref. POCI-01-0145-FEDER-016886), as well as through grant UID/FIS/04434/2013 (POCI-01-0145-FEDER-007672). P.F. and N.C.S. also acknowledge the support from FCT through Investigador FCT contracts of reference IF/01037/2013, IF/00169/2012, and IF/00028/2014, respectively, and POPH/FSE (EC) by FEDER funding through the program âPrograma Operacional de Factores de Competitividade - COMPETEâ. P.F. further acknowledge support from FCT in the form of exploratory projects of reference IF/01037/2013CP1191/CT0001 and IF/00028/2014/CP1215/CT0002. PJA acknowledges financial support from AYA2011-30147-C03-01 and AYA2014-54348-C3-1-R by MINECO/Spain, partially supported by FEDER funds/EU. Research activities of the Board of Stellar Astronomy, at the Federal University of Rio Grande do Norte are supported by continuous grant of CNPq, FAPERN and CAPES brazilian agencies and by the INCT INEspaço. E.D.M and V.Zh.A. also acknowledge the support from the FCT (Portugal) in the form of the grants SFRH/BPD/76606/2011 and SFRH/BPD/70574/2010, respectively
Short-term spectroscopic variability in the pre-main sequence Herbig AE star AB Aurigae during the MUSICOS 96 campaign
'By these means the sacred discourses sink more deeply into the minds of men': music and education in Elizabethan England
This article seeks to cast fresh light on the connections between music, education and the Reformation in Elizabethan England. Plato and Aristotle attributed to music a sovereign role and efficacy in education, and these notions were seized upon by religious reformers during the sixteenth century. The power of music to aid in the processes of learning and the absorption of holy doctrine made it an invaluable tool of religious pedagogy even in the eyes of Puritan critics of music in public worship. During the Renaissance, music was squeezed out of the majority of formal school curricula, but the practice of metrical psalmody in schools was more common than this might suggest. The laity more generally were the target of a panoply of religious instructional musical forms, including hymns, graces, and other scriptural, liturgical and catechetical versifications. Almost half of all Elizabethan godly ballads were written with a didactic function in mind and, while they rarely communicated a complex doctrinal or theological message, they sat comfortably within a staunchly Protestant conception of belief as practice. Elizabethan society was a musical place, and the education and eventual Protestantization of the Elizabethan people was, at least in part, a musical phenomenon
WASP-12b: the hottest transiting extrasolar planet yet discovered
We report on the discovery of WASP-12b, a new transiting extrasolar planet with R-pl = 1.79(-0.09)(+0.09) R-J and M-pl = 1.41(-0.01)(+0.01) M-J. The planet and host star properties were derived from a Monte Carlo Markov chain analysis of the transit photometry and radial velocity data. Furthermore, by comparing the stellar spectrum with theoretical spectra and stellar evolution models, we determined that the host star is a supersolar metallicity ([M/II]= 0.3(-0.15)(+0.15)), late-F (T-eff = 6300(-100)(+200) K) star which is evolving off the zero-age main sequence. The planet has an equilibrium temperature of T-eq = 2516 K caused by its very short period orbit (P = 1.09 days) around the hot, twelfth magnitude host star. WASP-12b has the largest radius of any transiting planet yet detected. It is also the most heavily irradiated and the shortest period planet in the literature