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MINCE: III. Detailed chemical analysis of the UVES sample
(EDP Sciences, 0025-03) Lucertini F.; Sbordone L.; Caffau E.; Bonifacio P; Monaco L; Cescutti G; Lallement R.; François P. b; Spitoni E.; Hansen C.J; Korn A.J.; Kučinskas A
Context. The Measuring at Intermediate Metallicity Neutron-Capture Elements (MINCE) project aims to provide high-quality neutron-capture abundances measurements for several hundred stars at an intermediate metallicity of -2.5 < [Fe/H] < -1.5. This project will shed light on the origin of the neutron-capture elements and the chemical enrichment of the Milky Way. Aims. The goal of this work is to chemically characterize the second sample of the MINCE project and compare the abundances with the galactic chemical evolution model at our disposal. Methods. We performed a standard abundance analysis based on one-dimensional (1D) local thermodynamic equilibrium (LTE) model atmospheres based on high-resolution and high-signal-to-noise-ratio (S/N) spectra from Ultraviolet and Visual Echelle Spectrograph (UVES). Results. We provide the kinematic classification (i.e., thin disk, thick disk, thin-to-thick disk, halo, Gaia Sausage Enceladus, Sequoia) of 99 stars and the atmospheric parameters for almost all stars. We derived the abundances for light elements (from Na to Zn) and neutron-capture elements (Rb, Sr, Y, Zr, Ba, La, Ce, Pr, Nd, Sm, and Eu) for a subsample of 32 stars in the metallicity range of -2.5 < [Fe/H] < -1.00. In the subsample of 32 stars, we identified eight active stars exhibiting (inverse) P-Cygni profile and one Li-rich star, CD 28-11039. We find a general agreement between the chemical abundances and the stochastic model computed for the chemical evolution of the Milky Way halo for elements Mg, Ca, Si, Ti, Sc, Mn, Co, Ni, Zn, Rb, Sr, Y, Zr, Ba, La, and Eu. Conclusions. The MINCE project has already significantly increased the number of neutron-capture elements measurements in the intermediate metallicity range. The results from this sample are in perfect agreement with the previous MINCE sample. The good agreement between the chemical abundances and the chemical evolution model of the Galaxy supports the nucleosynthetic processes adopted to describe the origin of the n-capture elements. © The Authors 2025.
ODIN: High Clustering Strength of Protoclusters at Cosmic Noon
(Institute of Physics, 0025-04) Ramakrishnan, Vandana; Lee, Kyoung-Soo; Firestone, Nicole; Gawiser, Eric; Artale, Maria Celeste; Gronwall, Caryl; Guaita, Lucia; Hwang, Ho Seong; Im, Sang Hyeok; Jeong, Woong-Seob; Kim, Seongjae; Kumar, Ankit
The One-hundred-deg2 DECam Imaging in Narrowbands (ODIN) survey is carrying out a systematic search for protoclusters during Cosmic Noon, using Lyα-emitting galaxies (LAEs) as tracers. Once completed, ODIN aims to identify hundreds of protoclusters at redshifts of 2.4, 3.1, and 4.5 across seven extragalactic fields, covering a total area of up to 91 deg2. In this work, we report the high clustering strength of the ODIN protoclusters, determined via measurements of their cross-correlation with LAEs. Our sample consists of 150 protocluster candidates at z = 2.4 and 3.1, identified in two ODIN fields with a total area of 13.9 deg2. At z = 2.4 and 3.1, the inferred protocluster biases are 6 . 6 − 1.1 + 1.3 and 6 . 1 − 1.1 + 1.3 , corresponding to mean halo masses of log 〈 M / M ⊙ 〉 = 13.5 3 − 0.24 + 0.21 and 12.9 6 − 0.33 + 0.28 , respectively. By the present day, these protoclusters are expected to evolve into virialized galaxy clusters with a mean mass of ∼1014.5 M⊙. By comparing the observed number density of protoclusters to that of halos with the same measured clustering strength, we find that the completeness of our sample is of order unity. Finally, the similar descendant masses derived for our samples at z = 2.4 and 3.1, assuming that the halo number density remains constant, suggest that they represent similar structures observed at different cosmic epochs. As a consequence, any observed differences between the two samples can be understood as redshift evolution. The ODIN protocluster samples will thus provide valuable insights into the cosmic evolution of cluster galaxies. © 2025. The Author(s). Published by the American Astronomical Society.
A Janovec-Kay-Dunn-Like Behavior at Thickness Scaling in Ultra-Thin Antiferroelectric ZrO2 Films
(John Wiley and Sons Inc, 2021-11) Tasneem, Nujhat; Yousry, Yasmin Mohamed; Tian, Mengkun; Dopita, Milan; Reyes-Lillo, Sebastian E.; Kacher, Josh; Bassiri-Gharb, Nazanin; Khan, Asif Islam
Originally based on phenomenological observations, the Janovec–Kay–Dunn (JKD) scaling law has been historically used to describe the dependence of the ferroelectric coercive fields (Ec) on a critical length scale of the material, wherein the film thickness (t) is considered the length scale, and Ec ∝ t−2/3. Here, for the first time, a JKD-type scaling behavior is reported in an antiferroelectric material, using the ultra-thin films of prototypical flourite-structure binary oxide, zirconia. In these films, a decrease in the ZrO2 layer thickness from 20 nm to 5.4 nm leads to an increase in critical fields for both nonpolar-to-polar (Ea), and polar-to-nonpolar (Ef) transitions, accompanied by a decrease in the average crystallite size, and an increase in the tetragonal distortion of the non-polar P42/nmc ground state structure. Notably, the -2/3 power law as in the JKD law holds when average crystallite size (d), measured from glancing-incident X-ray diffraction, is considered as the critical length scale—i.e., Ea, Ef ∝ d−2/3. First principles calculations suggest that the increase of tetragonality in thinner films contributes to an increase of the energy barrier for the transition from the non-polar tetragonal ground state to the field-induced polar orthorhombic phase, and in turn, an increase in Ea critical fields. These results suggest a de-stabilization of the ferroelectric phase with a decreasing thickness in antiferroelectric ZrO2, which is contrary to the observations in its fluorite-structure ferroelectric counterparts. With the recent interests in utilizing antiferroelectricity for advanced semiconductor applications, our fundamental exposition of the thickness dependence of functional responses therein can accelerate the development of miniaturized, antiferroelectric electronic memory elements for the complementary metal-oxide-semiconductor based high-volume manufacturing platforms. © 2021 Wiley-VCH GmbH
Exact formulation and analysis for the bi-objective insular traveling salesman problem
(MDPI, 2021-11-01) Miranda-Gonzalez, Pablo A.; Maturana-Ross, Javier; Blazquez, Carola A.; Cabrera-Guerrero, Guillermo
This paper aims at studying the Bi-Objective Insular Traveling Salesman Problem (BO-InTSP), which searches for a set of efficient, single visit sequences to collect (or distribute) freight from a set of islands. In this problem, the selection of ports (nodes) to be visited at each island, along with the associated port visit sequence, are optimized simultaneously, while the maritime transportation costs and the ground transportation costs inside the islands are minimized with a bi-objective perspective. This approach is employed since these costs are of a conflictive nature. A previous Approximated Formulation of the BO-InTSP relies on aggregating the actual demand locations within each island in a certain number of centroids for computing the ground transportation costs. Conversely, this paper proposes and develops a novel Exact Formulation for the problem based on the actual demand locations, instead of aggregating the demand inside the islands. Additionally, a systematic evaluation approach is developed to compare the two alternative formulations with different levels of demand aggregation inside the islands, considering the bi-objective nature of the problem. The results reveal that the novel Exact Formulation significantly outperforms the previous aggregated approach in terms of the solutions quality and computational resources. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
Denunciar violencia de pareja en Chile: Aspectos a considerar desde el Aparato Estatal
(Onati International Institute for the Sociology of Law, 2022-11) Marchant Espinoza, Juan Paulo
El presente ensayo analiza el actuar del Estado Chileno para facilitar las condiciones necesarias para que las personas ejerzan su derecho a denunciar actos de violencia en el contexto de pareja, cuando han sido víctimas de ello. Esto último, desde una mirada que integra las teorías del ciclo de las políticas públicas, la capacidad estatal, el marco normativo jurídico y la perspectiva de género. Lo anterior, a partir de una entrevista realizada a un informante clave dentro del contexto de levantamiento de información para mi investigación doctoral. Este ensayo analiza las acciones del Estado chileno para facilitar las condiciones necesarias para que las personas ejerzan su derecho a denunciar actos de violencia en el contexto de la pareja, cuando han sido víctimas de ella. Esto último, desde una perspectiva que integra las teorías del ciclo de las políticas públicas, la capacidad del Estado, el marco legal y la perspectiva de género. Lo anterior, a partir de una entrevista con una informante clave en el contexto de la recopilación de información para mi investigación doctoral.