Propiedades de las Nebulosas Planetarias mediante el satélite Gaia

Programa Oficial de Doutoramento en Tecnoloxías da Información e as Comunicacións. 5032V01[Resumen] La alta precisión de los parámetros astrométricos y fotométricos proporcionados por elsatélite Gaia de la ESA (European Space Agency), nos ha permitido estudiar y analizar en profundidad las propiedades físicas, químicas y evolutivas de las estrellas en fase de Nebulosa Planetaria (NP). Primeramente, partiendo de las coordenadas de las NPs ya conocidas, hemos desarrollado un algoritmo que identifica la fuente estelar de Gaia más probable de ser la Estrella Central (EC) de cada una de las NPs. A continuación, mediante la paralaje de estas fuentes, hemos podido estimar sus distancias, y seleccionar una muestra (de NPs con las distancias más precisas) sobre la que trabajar. El conocimiento de las distancias nos ha permitido calcular las propiedades intrínsecas de las NPs y de sus ECs a partir de sus propiedades observacionales. Para posteriormente poder estudiar su estado evolutivo, y analizar la binariedad de varias ECNPs. Además, también hemos llevado a cabo un estudio similar sobre las estrellas en fase de post-AGB, fase estelar previa a la NP. Por último, hemos realizado un análisis sobre la composición química de alguna de estas nebulosas, partiendo de los espectros detectados en el Observatorio de La Palma, y obteniendo resultados tanto de sus abundancias iónicas como elementales.[Abstract] The high precision of the astrometric and photometric parameters provided by the ESA (European Space Agency) Gaia satellite, has allowed us to study and analyse in depth the physical, chemical and evolutionary properties of stars in the Planetary Nebula (PN) phase. First, from the coordinates of the known PNe, we have developed an algorithm that identifies the most likely Gaia star source to be the Central Star (CS) of each of the PNe. Then, from the parallaxes of these sources, we have been able to estimate their distances, and to select a sample (composed by PNe with the most precise distances) on which to work. The knowledge of the distances has allowed us to calculate the intrinsic properties of the PNe and their CSs from their observational properties. To then be able to study their evolutionary state, and to analyse the binarity of various CSPNe. We have also made a similar study over stars in the post-AGB phase, the stellar phase previous to PN. Finally, we have carried out an analysis about the chemical composition of some of these nebulae, based on the spectra detected at the La Palma Observatory, and obtaining results of both their ionic and elemental abundances.[Resumo] A alta precisión dos parámetros astrométricos e fotométricos proporcionados polo satéliteGaia da ESA ( European Space Agency), permitiunos estudar e analizar en profundidade as propiedades físicas, químicas e evolutivas das estrelas en fase de Nebulosa Planetaria (NP). Primeiramente, partindo das coordenadas das NPs xa coñecidas, desenvolvimos un algorítmo que identifica a fonte estelar de Gaia máis probable de ser a Estréla Central (EC) de cada unha das NPs. A continuación, mediante a paralaxe destas fontes, puidemos estimar as súas distancias, e seleccionar unha mostra (de NPs coas distancias máis precisas) sobre a que traballar. O coñecemento das distancias permitiunos calcular as propiedades intrínsecas das NPs e de suas ECs a partir das súas propiedades observacionales. Para posteriormente poder estudar o seu estado evolutivo, e analizar o binariedad de varias ECNPs. Ademais, tamén levamos a cabo un estudo similar sobre as estrelas en fase de post-AGB, fase estelar previa á NP. Por último, realizamos unha análise sobre a composición química dalgunha destas nebulosas, partindo dos espectros detectados no Observatorio da Palma, e obtendo resultados tanto das súas abundancias iónicas como elementais

Close Binary Stars in Planetary Nebulae through Gaia EDR3

This article belongs to the Proceedings of The 4th XoveTIC Conference[Abstract] The aim of this work is to search for evidence of close binary stars associated with planetary nebulae (ionized stellar envelopes in expansion) by mining the astronomical archive of Gaia EDR3. For this task, using big data techniques, we selected a sample of central stars of planetary nebulae from almost 2000 million sources in an EDR3 database. Then, we analysed some of their parameters, which could provide clues about the presence of close binary systems, and we ran a statistical test to verify the results. Using this method, we concluded that red stars tend to show more affinity with close binarity than blue ones.Funding from Spanish Ministry project RTI2018-095076-B-C22, Xunta de Galicia ED431B 2021/36, and AYA-2017-88254-P is acknowledged by the authors. IGS acknowledges financial support from the Spanish National Programme for the Promotion of Talent and its Employability grant BES-2017-083126 cofunded by the European Social FundXunta de Galicia; ED431B 2021/3

Gaia DR2 Distances to Planetary Nebulae

[Abstract] The aim of this work is to examine distances to planetary nebulae (PNe) together with other properties that were derived from them, using the astrometry of Gaia Data Release 2 (DR2). We were able to identify 1571 objects classified as PNe, for which we assumed distances calculated following a Bayesian statistical approach. From those objects, we selected a sample of PNe with good quality parallax measurements and distance derivations, which we called Golden Astrometry PNe sample (GAPN). In this paper we will review the physical properties of the stars and nebulae in this subsample of PNe.Xunta de Galicia; ED431B 2018/42Funding from Spanish Ministry projects ESP2016-80079-C2-2-R, RTI2018-095076-BC22, Xunta de Galicia ED431B 2018/42, and AYA-2017-88254-P is acknowledged by the authors. M.M. thanks the Instituto de Astrofísica de Canarias for a visiting stay funded by the Severo Ochoa Excellence programme. IGS acknowledges financial support from the Spanish National Programme for the Promotion of Talent and its Employability grant BES-2017-083126 cofunded by the European Social Fun

Mining of the Milky Way Star Archive Gaia-DR2: Searching for Binary Stars in Planetary Nebulae

This article belongs to the Proceedings of 3rd XoveTIC Conference[Abstract] The aim of this work is to search for binary stars associated to planetary nebulae (ionized stellar envelopes in expansion), by mining the astronomical archive of Gaia DR2, that is composed by around 1.7 billion stellar sources. For this task, we selected those objects with coincident astrometric parameters (parallaxes and proper motions) with the corresponding central star, among a sample of 211 planetary nebulae. By this method, we found eight binary systems, and we obtained their components positions, separations, temperatures and luminosities, as well as some of their masses and ages. In addition, we estimated the probability for each companion star of having been detected by chance and we analyzed how the number of false matches increase as the separation distance between both stars gets larger. All these procedures have been carried out making use of data mining techniques.Funding from Spanish Ministry projects ESP2016-80079-C2-2-R, RTI2018-095076-BC22, Xunta de Galicia ED431B 2018/42, and AYA-2017-88254-P is acknowledged by the authors. M.M. thanks the Instituto de Astrofísica de Canarias for a visiting stay funded by the Severo Ochoa Excellence programme. IGS acknowledges financial support from the Spanish National Programme for the Promotion of Talent and its Employability grant BES-2017-083126 cofunded by the European Social FundXunta de Galicia; ED431B 2018/4

Gaia Early Data Release 3: Summary of the Contents and Survey Properties

This article has an erratum: [https://doi.org/10.1051/0004-6361/202039657e][Abstract] Context. We present the early installment of the third Gaia data release, Gaia EDR3, consisting of astrometry and photometry for 1.8 billion sources brighter than magnitude 21, complemented with the list of radial velocities from Gaia DR2. Aims. A summary of the contents of Gaia EDR3 is presented, accompanied by a discussion on the differences with respect to Gaia DR2 and an overview of the main limitations which are present in the survey. Recommendations are made on the responsible use of Gaia EDR3 results. Methods. The raw data collected with the Gaia instruments during the first 34 months of the mission have been processed by the Gaia Data Processing and Analysis Consortium and turned into this early third data release, which represents a major advance with respect to Gaia DR2 in terms of astrometric and photometric precision, accuracy, and homogeneity. Results. Gaia EDR3 contains celestial positions and the apparent brightness in G for approximately 1.8 billion sources. For 1.5 billion of those sources, parallaxes, proper motions, and the (GBP − GRP) colour are also available. The passbands for G, GBP, and GRP are provided as part of the release. For ease of use, the 7 million radial velocities from Gaia DR2 are included in this release, after the removal of a small number of spurious values. New radial velocities will appear as part of Gaia DR3. Finally, Gaia EDR3 represents an updated materialisation of the celestial reference frame (CRF) in the optical, the Gaia-CRF3, which is based solely on extragalactic sources. The creation of the source list for Gaia EDR3 includes enhancements that make it more robust with respect to high proper motion stars, and the disturbing effects of spurious and partially resolved sources. The source list is largely the same as that for Gaia DR2, but it does feature new sources and there are some notable changes. The source list will not change for Gaia DR3. Conclusions. Gaia EDR3 represents a significant advance over Gaia DR2, with parallax precisions increased by 30 per cent, proper motion precisions increased by a factor of 2, and the systematic errors in the astrometry suppressed by 30–40% for the parallaxes and by a factor ~2.5 for the proper motions. The photometry also features increased precision, but above all much better homogeneity across colour, magnitude, and celestial position. A single passband for G, GBP, and GRP is valid over the entire magnitude and colour range, with no systematics above the 1% levelXunta de Galicia; ED431B-2018/42Xunta de Galicia; ED481A-2019/155Xunta de Galicia; ED431G-2019/01Generalitat de Catalunya; 2014-SGR-1051https://doi.org/10.1051/0004-6361/202039657

Genomic lineages of Rhizobium etli revealed by the extent of nucleotide polymorphisms and low recombination

<p>Abstract</p> <p>Background</p> <p>Most of the DNA variations found in bacterial species are in the form of single nucleotide polymorphisms (SNPs), but there is some debate regarding how much of this variation comes from mutation versus recombination. The nitrogen-fixing symbiotic bacteria <it>Rhizobium etli </it>is highly variable in both genomic structure and gene content. However, no previous report has provided a detailed genomic analysis of this variation at nucleotide level or the role of recombination in generating diversity in this bacterium. Here, we compared draft genomic sequences versus complete genomic sequences to obtain reliable measures of genetic diversity and then estimated the role of recombination in the generation of genomic diversity among <it>Rhizobium etli</it>.</p> <p>Results</p> <p>We identified high levels of DNA polymorphism in <it>R. etli</it>, and found that there was an average divergence of 4% to 6% among the tested strain pairs. DNA recombination events were estimated to affect 3% to 10% of the genomic sample analyzed. In most instances, the nucleotide diversity (π) was greater in DNA segments with recombinant events than in non-recombinant segments. However, this degree of recombination was not sufficiently large to disrupt the congruence of the phylogenetic trees, and further evaluation of recombination in strains quartets indicated that the recombination levels in this species are proportionally low.</p> <p>Conclusion</p> <p>Our data suggest that <it>R. etli </it>is a species composed of separated lineages with low homologous recombination among the strains. Horizontal gene transfer, particularly via the symbiotic plasmid characteristic of this species, seems to play an important role in diversity but the lineages maintain their evolutionary cohesiveness.</p

Planetary nebulae in Gaia EDR3: Central star identification, properties, and binarity

Context. The Gaia Early Data Release 3 (EDR3), published in December 2020, features improved photometry and astrometry compared to that published in the previous DR2 file and includes a substantially larger number of sources, of the order of 2000 million, making it a paradigm of big data astronomy. Many of the central stars of planetary nebulae (CSPNe) are inherently faint and difficult to identify within the field of the nebula itself. Gaia measurements may be relevant not only in identifying the ionising source of each nebula, but also in the study their physical and evolutionary properties. Aims. We demonstrate how Gaia data mining can effectively help to solve the issue of central star misidentification, a problem that has plagued the field since its origin. As we did for DR2, our objective is to present a catalogue of CSPNe with astrometric and photometric information in EDR3. From that catalogue, we selected a sample of stars with high-quality astrometric parameters, on which we carried out a more accurate analysis of CSPNe properties. Methods.GaiaGBP − GRP colours allow us to select the sources with sufficient temperatures to ionise the nebula. In order to estimate the real colour of a source, it is important to take into account interstellar extinction and, in the case of compact nebulae, nebular extinction when available. In addition, distances derived from EDR3 parallaxes (combined with consistent literature values) can be used to obtain nebular intrinsic properties from those observed. With this information, CSPNe can be plotted in an Hertzsprung-Russell diagram. From information on the spectral classification of the CS (from the literature) and evolutionary models for post-AGB stars, their evolutionary state can then be analysed. Furthermore, EDR3 high-quality astrometric data enable us to search for objects comoving with CSs in the field of each nebula by detecting sources with parallaxes and proper motions similar to those of the CS. Results. We present a catalogue of 2035 PNe with their corresponding CS identification from among Gaia EDR3 sources. We obtain the distances for those with known parallaxes in EDR3 (1725 PNe). In addition, for a sub-sample (405 PNe) with the most accurate distances, we obtain different nebular properties such as their Galactic distribution, radius, kinematic age, and morphology. Furthermore, for a set of 74 CSPNe, we present the evolutionary state (mass and age) derived from their luminosities and effective temperatures from evolutionary models. Finally, we highlight the detection of several wide binary CSPNe through an analysis of the EDR3 astrometric parameters, and we contribute to shedding some light on the relevance of close binarity in CSPNe.Agencia Estatal de Investigación | Ref. AYA2017-84089-PAgencia Estatal de Investigación | Ref. RTI2018-095076-B-C22Agencia Estatal de Investigación | Ref. PDC2021-121059-C22Agencia Estatal de Investigación | Ref. AYA2017-88254-PXunta de Galicia | Ref. ED431G 2019/01Agencia Estatal de Investigación | Ref. BES-2017-08312

Spatial patterns in phage-Rhizobium coevolutionary interactions across regions of common bean domestication

Bacteriophages play significant roles in the composition, diversity, and evolution of bacterial communities. Despite their importance, it remains unclear how phage diversity and phage-host interactions are spatially structured. Local adaptation may play a key role. Nitrogen-fixing symbiotic bacteria, known as rhizobia, have been shown to locally adapt to domesticated common bean at its Mesoamerican and Andean sites of origin. This may affect phage-rhizobium interactions. However, knowledge about the diversity and coevolution of phages with their respective Rhizobium populations is lacking. Here, through the study of four phage-Rhizobium communities in Mexico and Argentina, we show that both phage and host diversity is spatially structured. Cross-infection experiments demonstrated that phage infection rates were higher overall in sympatric rhizobia than in allopatric rhizobia except for one Argentinean community, indicating phage local adaptation and host maladaptation. Phage-host interactions were shaped by the genetic identity and geographic origin of both the phage and the host. The phages ranged from specialists to generalists, revealing a nested network of interactions. Our results suggest a key role of local adaptation to resident host bacterial communities in shaping the phage genetic and phenotypic composition, following a similar spatial pattern of diversity and coevolution to that in the host.Fil: Van Cauwenberghe, Jannick. University of California at Berkeley; Estados Unidos. Universidad Nacional Autónoma de México; MéxicoFil: Santamaría, Rosa I.. Universidad Nacional Autónoma de México; MéxicoFil: Bustos, Patricia. Universidad Nacional Autónoma de México; MéxicoFil: Juárez, Soledad. Universidad Nacional Autónoma de México; MéxicoFil: Ducci, Maria Antonella. Universidad Nacional de Salta; Argentina. Instituto Nacional de Tecnología Agropecuaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; ArgentinaFil: Figueroa Fleming, Trinidad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; Argentina. Universidad Nacional de Salta; ArgentinaFil: Etcheverry, Angela Virginia. Universidad Nacional de Salta; ArgentinaFil: González, Víctor. Universidad Nacional Autónoma de México; Méxic

Internet gaming disorder clustering based on personality traits in adolescents, and its relation with comorbid psychological symptoms

Altres ajuts: This work was funded by an AIS (Atención e Investigación en Socioaddiciones) intramural research program. This research is partially supported by the Marsden grant E2987-3648 (Royal Society of New Zealand).In recent years, the evidence regarding Internet Gaming Disorder (IGD) suggests that some personality traits are important risk factors for developing this problem. The heterogeneity involved in problematic online gaming and differences found in the literature regarding the comorbid psychopathology associated with the problem could be explained through different types of gamers. Clustering analysis can allow organization of a collection of personality traits into clusters based on similarity. The objectives of this study were: (1) to obtain an empirical classification of IGD patients according to personality variables and (2) to describe the resultant groups in terms of clinical and sociodemographic variables. The sample included 66 IGD adolescent patients who were consecutive referrals at a mental health center in Barcelona, Spain. A Gaussian mixture model cluster analysis was used in order to classify the subjects based on their personality. Two clusters based on personality traits were detected: type I "higher comorbid symptoms" (n = 24), and type II "lower comorbid symptoms" (n = 42). The type I included higher scores in introversive, inhibited, doleful, unruly, forceful, oppositional, self-demeaning and borderline tendency traits, and lower scores in histrionic, egotistic and conforming traits. The type I obtained higher scores on all the Symptom Check List-90 items-Revised, all the State-Trait Anxiety Index scales, and on the DSM-5 IGD criteria. Differences in personality can be useful in determining clusters with different types of dysfunctionality