478 research outputs found
High resolution spectroscopic analysis of seven giants in the bulge globular cluster NGC 6723
Globular clusters associated with the Galactic bulge are important tracers of
stellar populations in the inner Galaxy. High resolution analysis of stars in
these clusters allows us to characterize them in terms of kinematics,
metallicity, and individual abundances, and to compare these fingerprints with
those characterizing field populations. We present iron and element ratios for
seven red giant stars in the globular cluster NGC~6723, based on high
resolution spectroscopy. High resolution spectra () of seven K
giants belonging to NGC 6723 were obtained with the FEROS spectrograph at the
MPG/ESO 2.2m telescope. Photospheric parameters were derived from FeI
and FeII transitions. Abundance ratios were obtained from line-to-line spectrum
synthesis calculations on clean selected features. An intermediate metallicity
of [Fe/H] dex and a heliocentric radial velocity of
were found for NGC 6723. Alpha-element
abundances present enhancements of dex,
dex, dex, and
dex. Similar overabundance is found for the iron-peak Ti with
dex. Odd-Z elements Na and Al present abundances of
dex and dex, respectively. Finally,
the s-element Ba is also enhanced by dex. The enhancement
levels of NGC 6723 are comparable to those of other metal-intermediate bulge
globular clusters. In turn, these enhancement levels are compatible with the
abundance profiles displayed by bulge field stars at that metallicity. This
hints at a possible similar chemical evolution with globular clusters and the
metal-poor of the bulge going through an early prompt chemical enrichment
La transición de la ortografía casera a la académica en un corpus de folletos políticos chilenos (1880-1939)
This article aims at contributing to the documentation of the transition from the spelling system known as ortografía chilena (‘Chilean orthography’) or ortografía casera (‘domestic orthography’) to that of the Royal Spanish Academy in Chile by studying the collection of political pamphlets made available to the public digitally by the Library of the National Congress of Chile. The analysis of 35 pamphlets printed between 1880 and 1939 shows a progressive adoption of the academic model, which by 1910 already seemed widely predominant. Thus, the possibility is raised that the 1927 decree establishing the adoption of the academic orthography was but the official reaffirmation of a tendency noticeable in the country since almost two decades before, at least as far as the genre under study is concerned.Este artículo busca contribuir en la documentación de la transición de la ortografía llamada chilena o casera a la de la Real Academia Española en Chile a través del estudio de la colección de folletos políticos que la Biblioteca del Congreso Nacional de Chile ha puesto a disposición del público en formato digital. El análisis de 35 folletos impresos entre 1880 y 1939 muestra una progresiva adopción del modelo académico, el cual ya a partir de la década de 1910 se muestra como ampliamente predominante. En consecuencia, se plantea la posibilidad de que el decreto de 1927 que estableció la adopción de la ortografía académica no fuera más que la reafirmación oficial de una tendencia observable hacía ya casi dos décadas en el país, al menos por lo que respecta al género en estudio
The GIRAFFE Inner Bulge Survey (GIBS). I. Survey Description and a kinematical map of the Milky Way bulge
The Galactic bulge is a massive, old component of the Milky Way. It is known
to host a bar, and it has recently been demonstrated to have a pronounced
boxy/peanut structure in its outer region. Several independent studies suggest
the presence of more than one stellar populations in the bulge, with different
origins and a relative fraction changing across the bulge area. This is the
first of a series of papers presenting the results of the Giraffe Inner Bulge
Survey, carried out at the ESO-VLT with the multifibre spectrograph FLAMES.
Spectra of ~5000 red clump giants in 24 bulge fields have been obtained at
resolution R=6500, in the infrared Calcium triplet wavelength region at 8500
{\AA}. They are used to derive radial velocities and metallicities, based on
new calibration specifically devised for this project. Radial velocities for
another ~1200 bulge red clump giants, obtained from similar archive data, have
been added to the sample. Higher resolution spectra have been obtained for 450
additional stars at latitude b=-3.5, with the aim of investigating chemical
abundance patterns variations with longitude, across the inner bulge. In total
we present here radial velocities for 6392 RC stars. We derive a radial
velocity, and velocity dispersion map of the Milky Way bulge, useful to be
compared with similar maps of external bulges, and to infer the expected
velocities and dispersion at any line of sight. The K-type giants kinematics is
consistent with the cylindrical rotation pattern of M-giants from the BRAVA
survey. Our sample enables to extend this result to latitude b=-2, closer to
the Galactic plane than probed by previous surveys. Finally, we find strong
evidence for a velocity dispersion peak at (0,-1) and (0,-2), possibly
indicative of a high density peak in the central 250 pc of the bulgeComment: A&A in pres
A comprehensive meta-QTL analysis for yield-related traits of durum wheat (Triticum turgidum L. var. durum) grown under different water regimes
Abiotic stress strongly affects yield-related traits in durum wheat, in particular drought is one of the main environmental factors that have effect on grain yield and plant architecture. In order to obtain new genotypes well adapted to stress conditions, the highest number of desirable traits needs to be combined in the same genotype. In this context, hundreds of quantitative trait loci (QTL) have been identified for yield-related traits in different genetic backgrounds and environments. Meta-QTL (MQTL) analysis is a useful approach to combine data sets and for creating consensus positions for the QTL detected in independent studies for the reliability of their location and effects. MQTL analysis is a useful method to dissect the genetic architecture of complex traits, which provide an extensive allelic coverage, a higher mapping resolution and allow the identification of putative molecular markers useful for marker-assisted selection (MAS). In the present study, a complete and comprehensive MQTL analysis was carried out to identify genomic regions associated with grain-yield related traits in durum wheat under different water regimes. A total of 724 QTL on all 14 chromosomes (genomes A and B) were collected for the 19 yield-related traits selected, of which 468 were reported under rainfed conditions, and 256 under irrigated conditions. Out of the 590 QTL projected on the consensus map, 421 were grouped into 76 MQTL associated with yield components under both irrigated and rainfed conditions, 12 genomic regions containing stable MQTL on all chromosomes except 1A, 4A, 5A, and 6B. Candidate genes associated to MQTL were identified and an in-silico expression analysis was carried out for 15 genes selected among those that were differentially expressed under drought. These results can be used to increase durum wheat grain yields under different water regimes and to obtain new genotypes adapted to climate change
A detailed analysis of the HD 73526 2:1 resonant planetary system
We present six years of new radial velocity data from the Anglo-Australian and Magellan Telescopes on the HD 73526 2:1 resonant planetary system. We investigate both Keplerian and dynamical ( interacting) fits to these data, yielding four possible configurations for the system. The new data now show that both resonance angles are librating, with amplitudes of 40 degrees and 60 degrees, respectively. We then perform long-term dynamical stability tests to differentiate these solutions, which only differ significantly in the masses of the planets. We show that while there is no clearly preferred system inclination, the dynamical fit with i = 90 degrees provides the best combination of goodness-of-fit and long-term dynamical stability.Peer reviewe
HATS-15 b and HATS-16 b: Two massive planets transiting old G dwarf stars
We report the discovery of HATS-15 b and HATS-16 b, two massive transiting
extrasolar planets orbiting evolved ( Gyr) main-sequence stars. The
planet HATS-15 b, which is hosted by a G9V star ( mag), is a hot
Jupiter with mass of and radius of
, and completes its orbit in nearly 1.7 days.
HATS-16 b is a very massive hot Jupiter with mass of and radius of ; it orbits around
its G3 V parent star ( mag) in days. HATS-16 is slightly
active and shows a periodic photometric modulation, implying a rotational
period of 12 days which is unexpectedly short given its isochronal age. This
fast rotation might be the result of the tidal interaction between the star and
its planet.Comment: 16 pages, 8 figures, submitted to PAS
Initial Validation of the International Trauma Questionnaire (ITQ) in a sample of Chilean Adults
ABSTRACTBackground: ICD-11 Posttraumatic Stress Disorder (PTSD) and Complex PTSD (CPTSD) are stress-related disorders. The International Trauma Questionnaire (ITQ) is a widely used instrument to assess PTSD and CPTSD. To date, there is no evidence of the psychometric characteristics of the ITQ in Latin American countries.Objective: The aim of this study was to assess the construct and concurrent validity of the Latin American Spanish adaptation of the ITQ in a sample of Chilean adults.Methods: A sample of 275 Chilean young adults completed the ITQ, a traumatic life events checklist, the Adverse Childhood Experiences Questionnaire, the Depression Anxiety Stress Scales-21, and the Columbia-Suicide Severity Rating Scale short version. Four alternative confirmatory factor analysis models were tested. Correlation analyses were performed to determine concurrent validity with associated measures (number of reported traumatic events, number of adverse childhood experiences, anxiety, depression, and suicidal risk).Results: The second-order two-factor (PTSD and DSO) and the correlated first-order six-factor model provided acceptable fit; however, the first model showed a better fit based on the BIC difference. The PTSD and DSO dimensions, as well as the six ITQ clusters showed positive correlations with reported number of traumatic life-events, reported number of adverse childhood experiences, levels of anxiety, depression, and suicidal risk.Conclusions: The ITQ Latin American Spanish adaptation provides acceptable psychometric evidence to assess PTSD and CPTSD in accordance with the ICD-11
The VVV survey: Long-period variable stars I. Photometric catalog of ten VVV/OGLE tiles
Long-period variable stars (LPVs) are pulsating red giants, primarily in the
asymptotic giant branch phase, and they include both Miras and semi-regular
variables (SRVs). Their period-age and period-luminosity relations enable us to
trace different stellar populations, as they are intrinsically very bright and
cover a wide range in distances and ages. The purpose of this study is to
establish a census of LPV stars in a region close to the Galactic center, using
the six-year database of the Vista Variables in the V\'ia L\'actea (VVV) ESO
Public Survey, as well as to describe the methodology that was employed to
search for and characterize LPVs using VVV data. Near-IR surveys such as VVV
provide a unique opportunity to probe the high-extinction innermost regions of
the Milky Way. The detection and analysis of the intrinsically bright Miras in
this region could provide us with an excellent probe of the properties of the
Milky Way far behind its bulge. We used point-spread function photometry for
all available -band images in ten VVV tiles, covering in
total, overlapping fields observed in the course of the Optical Gravitational
Lensing Experiment (OGLE)-III survey. We designed a method to select LPV
candidates, and we used the known variables from OGLE-III and other known
variables from the literature to test our approach. The reduced
statistic, along with the flux-independent index , were used in our
analysis. The Lomb-Scargle period search method, Fourier analysis, template
fitting, and visual inspection were then performed to refine our sample and
characterize the properties of the stars included in our catalog. A final
sample of 130 Mira candidates, of which 129 are new discoveries, was thus
obtained, with periods in the range between about 80 and 1400~days
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