Resultados de investigación

The CARMENES instrument, installed at the 3.5-m telescope of the Calar Alto observatory in Almeria, Spain, was conceived to deliver high-accuracy radial velocity (RV) measurements with long-term stability to search for temperate rocky planets around a sample of nearby cool stars. Moreover, the broad wavelength coverage was designed to provide a range of stellar activity indicators to assess the nature of potential RV signals and also valuable spectral information to characterise the stellar targets. Here, we describe the CARMENES Guaranteed Time Observations (GTO), which ran from 2016 to 2020 and collected 19633 spectra for a sample of 362 targets. We present the CARMENES Data Release 1 (DR1), which makes public all observations obtained during the GTO of the CARMENES survey. The CARMENES survey target selection was aimed at minimising biases and about 70% of all known M dwarfs within 10 pc accessible from Calar Alto were included. The data are pipeline-processed and high-level data products, including 18642 precise RVs for 345 targets, are derived. Time series data of spectroscopic activity indicators are also obtained. We discuss the characteristics of CARMENES data and the statistical properties of the stellar sample and the spectroscopic measurements. We show examples of the use of CARMENES data and provide a contextual view of the exoplanet population revealed by the survey, including 33 new planets, 17 reanalysed planets, and 26 confirmed planets from transiting candidate follow-up. A subsample of 238 targets is used to derive updated planet occurrence rates, yielding an overall average of 1.44+/-0.20 planets with 1M_{Earth}_, In Table 1, we provide the the list of stars of the CARMENES GTO survey included in the data release DR1. Star identifier, the number of radial velocity measurements and spectra, the mass, the radius, the effective temperature, and the rotation period (if known) of each star are listed. The nightly zero point radial velocity average value used to correct data from instrumental systematics are given in Table 2. The radial velocity correction, its uncertainty, the number of measurements averaged, and a quality flag are provided for each night., Financial support from the Severo Ochoa grant CEX2021-001131-S funded by MCIN/AEI/ 10.13039/501100011033, No

We present the detection of 68 sources from the most sensitive radio survey in circular polarisation conducted to date. We used the second data release of the 144MHz LOFAR Two-metre Sky Survey to prodce circularly polarised maps with a median noise of 140uJy/beam and resolution of 20-arcsec for 27% of the northern sky (5634deg^2^). The leakage of total intensity into circular polarisation is measured to be ~0.06%, and our survey is complete at flux densities >=1mJy. A detection is considered reliable when the circularly polarised fraction exceeds 1%. We find the population of circularly polarised sources is composed of four distinct classes: stellar systems, pulsars, active galactic nuclei, and sources unidentified in the literature. The stellar systems can be further separated into chromospherically active stars, M dwarfs, and brown dwarfs. Based on the circularly polarised fraction and lack of an optical counterpart, we show it is possible to infer whether the unidentified sources are likely unknown pulsars or brown dwarfs. By the completion of this survey of the northern sky, we expect to detect 300+/-100 circularly polarised sources., The column numbers, names, and units for the V-LoTSS catalogue are described below. All Stokes I information is similar to that found in the LoTSS-DR2 catalogue but can differ depending on whether the source is variable (Shimwell et al., 2022A&A...659A...1S, Cat. J/A+A/659/A1). For the few sources that are not present in LoTSS-DR2 because of their variability, we have formed their LoTSS name in line with the convention defined by (Shimwell et al., 2022A&A...659A...1S, Cat. J/A+A/659/A1). We report some Gaia DR3 measurements if the Stokes V source has a counterpart in that survey. Similarly, we report some pulsar properties if the source has a counterpart in Australia Telescope National Facility Pulsar Catalogue (PSRCAT; v1.68; Manchester et al., 2005AJ....129.1993M, Cat. B/psr). Full details can be found in the paper., Financial support from the Severo Ochoa grant CEX2021-001131-S funded by MCIN/AEI/ 10.13039/501100011033, No

We present the discovery of an Earth-mass planet (M_b_sini=1.36+/-0.21M_{Earth}_) on a 15.6d orbit of a relatively nearby (d~9.6pc) and low-mass (0.167+/-0.011M_{sun}_) M5.0V star, Wolf 1069. Sitting at a separation of 0.0672+/-0.0014au away from the host star puts Wolf 1069b in the habitable zone (HZ), receiving an incident flux of S=0.652+/-0.029S_{Earth}_. The planetary signal was detected using telluric-corrected radial-velocity (RV) data from the CARMENES spectrograph, amounting to a total of 262 spectroscopic observations covering almost four years. There are additional long-period signals in the RVs, one of which we attribute to the stellar rotation period. This is possible thanks to our photometric analysis including new, well-sampled monitoring campaigns undergone with the OSN and TJO facilities that supplement archival photometry (i.e., from MEarth and SuperWASP), and this yielded an updated rotational period range of P_rot_=150-170d, with a likely value at 169.3^+3.7^_-3.6_d. The stellar activity indicators provided by the CARMENES spectra likewise demonstrate evidence for the slow rotation period, though not as accurately due to possible factors such as signal aliasing or spot evolution. Our detectability limits indicate that additional planets more massive than one Earth mass with orbital periods of less than 10 days can be ruled out, suggesting that perhaps Wolf 1069b had a violent formation history. This planet is also the 6th closest Earth-mass planet situated in the conservative HZ, after Proxima Centauri b, GJ 1061d, Teegarden's Star c, and GJ 1002 b and c. Despite not transiting, Wolf 1069b is nonetheless a very promising target for future three-dimensional climate models to investigate various habitability cases as well as for sub-m/s RV campaigns to search for potential inner sub-Earth-mass planets in order to test planet formation theories., CARMENES VIS radial-velocity and stellar activity indicator time series of Wolf 1069. These were all processed with serval (Zechmeister et al., 2018A&A...609A..12Z). Photometric time series for Wolf 1069 with the following facilities: SuperWASP, MEarth, OSN, TJO, Financial support from the Severo Ochoa grant CEX2021-001131-S funded by MCIN/AEI/ 10.13039/501100011033, No

The environments where galaxies reside affects their evolutionary histories. Galaxy triplets (systems composed of three physically bound galaxies) are one of simplest groups of galaxies, and are therefore excellent laboratories to study evolutionary mechanisms where effects of the environment are minimal. We present a statistical study of the dynamical properties of isolated galaxy triplets as a function of their local and large-scale environments. To explore the connection of the dynamical evolution on the systems with the evolution of the galaxies composing the triplets, we consider observational properties such as morphology and star formation rate (SFR). We used the SDSS-based catalogue of Isolated Triplets (SIT), which contains 315 triplets. We classified each triplet according to galaxy morphologies and defined a parameter Qtrip to quantify the total local tidal strengths in the systems. To quantify the dynamical stage of the system we used the parameters of harmonic radius RH , velocity dispersion {sigma}_vr_, crossing time H_0_t_c_, and virial mass M_vir_. Triplets composed of three early-type galaxies present the smallest R_H_, indicating that they are in general more compact than triplets with one or more late-type galaxies. Among triplets with low values of R_H_ and H_0_t_c_, SIT triplets with Q_trip_<-2 are relaxed systems that are more dynamically evolved, while triplets with Q_trip_>-2 show compact configurations due to interactions within the system, such as ongoing mergers. We found that there is no dominant galaxy in triplets in terms of properties of stellar populations such as global colour and SFR. Moreover, the global SFR in isolated triplets composed of two or more early-type galaxies increases with the stellar mass ratio of the galaxies with respect to the central galaxy, therefore the system is globally 'rejuvenated'., Dynamical parameters (harmonic radius, velocity dispersion, crossing time, and virial mass), total local tidal strength (Q_trip_), and morphology categories for the 315 triplets in the SIT., Financial support from the Severo Ochoa grant CEX2021-001131-S funded by MCIN/AEI/ 10.13039/501100011033, No

"Cybele asteroids constitute an appealing reservoir of primitive material genetically linked to the outer Solar System, and the physical properties (size and shape) of the largest members can be readily accessed by large (8m class) telescopes. We took advantage of the bright apparition of the most iconic member of the Cybele population, (65) Cybele, in July and August 2021 to acquire high-angular-resolution images and optical light curves of the asteroid with which we aim to analyse its shape and bulk properties. Eight series of images were acquired with VLT/SPHERE+ZIMPOL, seven of which were combined with optical light curves to reconstruct the shape of the asteroid using the ADAM, MPCD, and SAGE algorithms. The origin of the shape was investigated by means of N-body simulations. Cybele has a volume-equivalent diameter of 263+/-3km and a bulk density of 1.55+/-0.19g/cm^3^. Notably, its shape and rotation state are closely compatible with those of a Maclaurin equilibrium figure. The lack of a collisional family associated with Cybele and the higher bulk density of that body with respect to other large P-type asteroids suggest that it never experienced any large disruptive impact followed by rapid re-accumulation. This would imply that its present-day shape represents the original one. However, numerical integration of the long-term dynamical evolution of a hypothetical family of Cybele shows that it is dispersed by gravitational perturbations and chaotic diffusion over gigayears of evolution. The very close match between Cybele and an equilibrium figure opens up the possibility that D>=260km (M>=1.5x10^19^kg) small bodies from the outer Solar System all formed at equilibrium. However, we cannot currently rule out an old impact as the origin of the equilibrium shape of Cybele. Cybele itself is found to be dynamically unstable, implying that it was ""recently"" (<1Gyr ago) placed on its current orbit either through slow diffusion from a relatively stable orbit in the Cybele region or, less likely, from an unstable, Jupiter-family-comet orbit in the planet-crossing region.", We obtained 70 images of Cybele at 7 epochs in 2021 using VLT/SPHERE/ZIMPOL. All images were reduced and deconvolved following the procedure described in Vernazza et al. (2018A&A...618A.154V). objects: ---------------------------------------------------------------- Planet Name H Diam i e a mag km deg AU ------------------------------------------------------------------- 65 Cybele 6.92 263 3.567994 0.116080 3.4390432 -------------------------------------------------------------------, Financial support from the Severo Ochoa grant CEX2021-001131-S funded by MCIN/AEI/ 10.13039/501100011033, No

[ES] "Summaries_of_meteorological_observations_from_the_Spanish_Meteorological_Service, v.2.0.0. [Dataset]" se compone de los datos de precipitación (total mensual y maximo diario mensual) y temperatura (media mensual de las maximas diarias, media mensual de las minimas diarias, maximo diario mensual, minimo diario mensual) de los Libros Resúmenes Anuales editados por los sucesivos Servicios Meteorológicos de España en el periodo 1915-1950. No se ha aplicado ningún procedimiento de tratamiento a los datos, son datos brutos lo más exactos posible procedentes de los Anuarios. El procedimiento de cotejo entre las observaciones de los Anuarios (LRAs) y las de la Base Nacional de Datos del Clima (BNDC) consistió en determinar, para cada estación que aparece en los LRAs, la estación a la que corresponde en la BNDC. No se trata de una tarea sencilla, ya que el nombre de un mismo observatorio en los LRAs puede aparecer de forma diferente en años sucesivos, mientras que, por otra parte, la fiabilidad de las coordenadas es escasa. En consecuencia, el cotejo en su primera fase se convirtió en una combinación de identificación de nombres de observatorio similares entre ambas fuentes junto con la búsqueda de cadenas de registros idénticas en la secuencia mensual de cada año. En las series anuales así identificadas como idénticas (o muy similares), se comprobó que tenían la misma localización provincial y que el nombre del observatorio era similar en ambas fuentes, teniendo en cuenta que su nombre puede aparecer de forma diferente a lo largo de los años. En una segunda fase, la información no emparejada por el proceso anterior se trató individualmente para cada caso (registro anual), buscando similitud de nombre y provincia si ampliaba series ya emparejadas, o si podía considerarse una nueva serie no incluida en la BNDC, en cuyo caso se estimaron sus coordenadas con precisión de 1 minuto de latitud y longitud. [EN] "Summaries_of_meteorological_observations_from_the_Spanish_Meteorological_Service, v.2.0.0. [Dataset]" is composed of precipitation (monthly total and monthly daily maximum) and temperature (monthly mean daily maximum, monthly mean daily minimum, monthly daily maximum, monthly daily minimum) data from the Annual Summary Books published by the successive Spanish Meteorological Services in the period 1915-1950. No processing procedure has been applied to the data, they are raw data as accurate as possible from the Annual Books (ABs). The matching procedure between the observations of the ABs and those of the National Climate Database (NCDB) consisted in determining, for each station appearing in the ABs, the station to which it corresponds in the NCDB. This is not a simple task, since the name of the same observatory in the ABs may appear differently in successive years, while, on the other hand, the reliability of the coordinates is poor. Consequently, the matching in its first phase became a combination of identification of similar observatory names between both sources together with the search for identical record strings in the monthly sequence of each year. In the annual series thus identified as identical (or very similar), it was found that they had the same provincial location and that the observatory name was similar in both sources, taking into account that its name may appear differently over the years. In a second phase, the information not matched by the previous process was treated individually for each case (annual record), looking for similarity of name and province if it extended series already matched, or if it could be considered a new series not included in the NCBD, in which case its coordinates were estimated with 1-minute precision of latitude and longitude., [ES] El conjunto de datos "Summaries_of_meteorological_observations_from_the_Spanish_Meteorological_Service" es el resultado de un proceso de digitalización de los datos publicados en los Resúmenes de las Observaciones Meteorológicas -realizados a nivel anual- y editados por el Servicios Meteorológico Español, periodo 1915-1950. Concretamente, la información digitalizada es la precipitación mensual y la precipitación máxima diaria mensual junto a la media mensual de las temperaturas máximas diarias, la media mensual de las temperaturas mínimas diarias y el valor máximo y el valor mínimo diario de temperatura a nivel mensual. Estos datos, combinados con los incluidos en el BNDC, han sido empleados para el desarrollo de las mallas de alta resolución denominadas MOPREDAS y MOTEDAS_1916-2015 y subsiguientes versiones, [EN] The data set "Summaries_of_meteorological_observations_from_the_Spanish_Meteorological_Service" is the result of a digitization process of the data published in the Summaries of Meteorological Observations -made at annual level- and edited by the Spanish Meteorological Service, period 1915-1950. Specifically, the digitized information is the monthly precipitation and the maximum daily monthly precipitation together with the monthly mean of the maximum daily temperatures, the monthly mean of the minimum daily temperatures and the maximum and minimum daily values of temperature at monthly level. These data, combined with those included in the BNDC, have been used for the development of the high-resolution grids called MOPREDAS and MOTEDAS_1916-2015 and subsequent versions., Project PID2020-116860RB-C22: Extremos térmicos y pluviométricos en la España peninsular 1916-2020), funded by the Spanish Ministry of Science., No

Hickson compact groups (HCGs) are dense configurations of four to ten galaxies, whose HI morphology appears to follow an evolutionary sequence of three phases, with gas initially confined to galaxies, then significant amounts spread throughout the intra-group medium, and finally with almost no gas remaining in the galaxies themselves. It has also been suggested that several groups may harbour a diffuse HI component that is resolved out by interferometric observations. The HI deficiency of HCGs is expected to increase as the HI morphological phase progresses along the evolutionary sequence. If this is the case, HI deficiency would be a rough proxy for the age and evolutionary state of a HCG. We aim to test this hypothesis for the first time using a large sample of HCGs and to investigate the evidence for diffuse HI in HCGs. We performed a uniform reduction of all publicly available VLA HI observations (38 HCGs) with a purpose-built pipeline that also maximises the reproducibility of this study. The resulting HI data cubes were then analysed with the latest software tools to perform a manual separation of emission features into those belonging to galaxies and those extending into the intra-group medium. We thereby classified the HI morphological phase of each group as well as quantified their HI deficiency compared to galaxies in isolation. We find little evidence that HI deficiency can be used as a proxy for the evolutionary phase of a compact group in either of the first two phases, with the distribution of HI deficiency being consistent in both. However, for the final phase, the distribution clearly shifts to high HI deficiencies, with more than 90% of the expected HI content typically missing. Across all HCGs studied, we identify a few cases where there is strong evidence for a diffuse gas component in the intra-group medium, which might be detectable with improved observations. We also classify a new sub-phase where groups contain a lone HI-bearing galaxy, but are otherwise devoid of gas. The new morphological phase we have identified is likely the result of an evolved, gas-poor group acquiring a new, gas-rich member. The large spread of HI deficiencies in the first two morphological phases suggests that there is a broad range of initial HI content in HCGs, which is perhaps influenced by large-scale environment, and that the timescale for morphological changes is, in general, considerably shorter than the timescale for the destruction or consumption of neutral gas in these systems., Here we present the tables of HI measurements from the paper., Financial support from the Severo Ochoa grant CEX2021-001131-S funded by MCIN/AEI/ 10.13039/501100011033, No

We report the discovery and characterisation of two Earth-mass planets orbiting in the habitable zone of the nearby M-dwarf GJ 1002 based on the analysis of the radial-velocity (RV) time series from the ESPRESSO and CARMENES spectrographs. The host star is the quiet M5.5 V star GJ 1002 (relatively faint in the optical, V~13.8mag, but brighter in the infrared, J~8.3mag), located at 4.84pc from the Sun. We analyse 139 spectroscopic observations taken between 2017 and 2021. We performed a joint analysis of the time series of the RV and full-width half maximum (FWHM) of the cross-correlation function (CCF) to model the planetary and stellar signals present in the data, applying Gaussian process regression to deal with the stellar activity. We detect the signal of two planets orbiting GJ 1002. GJ 1002 b is a planet with a minimum mass m_p_sini of 1.08+/-0.13M_{sun}_ with an orbital period of 10.3465+/-0.0027 days at a distance of 0.0457+/-0.0013au from its parent star, receiving an estimated stellar flux of 0.67F_{sun}_. GJ 1002 c is a planet with a minimum mass m_p_sini of 1.36+/-0.17M_{sun}_ with an orbital period of 20.202+/-0.013 days at a distance of 0.0738+/-0.0021au from its parent star, receiving an estimated stellar flux of 0.257F_{sun}_. We also detect the rotation signature of the star, with a period of 126+/-15 days. We find that there is a correlation between the temperature of certain optical elements in the spectrographs and changes in the instrumental profile that can affect the scientific data, showing a seasonal behaviour that creates spurious signals at periods longer than ~200 days. GJ 1002 is one of the few known nearby systems with planets that could potentially host habitable environments. The closeness of the host star to the Sun makes the angular sizes of the orbits of both planets (~9.7 mas and ~15.7mas, respectively) large enough for their atmosphere to be studied via high-contrast high-resolution spectroscopy with instruments such as the future spectrograph ANDES for the ELT or the LIFE mission., Radial velocity, FWHM and echelle temperature data of the observations of GJ 1002 with ESPRESSO and CARMENES., Financial support from the Severo Ochoa grant CEX2021-001131-S funded by MCIN/AEI/ 10.13039/501100011033, No

The rotational states of the members in the dwarf planet - satellite systems in the transneptunian region are determined by the formation conditions and the tidal interaction between the components, and these rotational characteristics are the prime tracers of their evolution. Previously a number of authors claimed highly diverse values for the rotation period for the dwarf planet Eris, ranging from a few hours to a rotation (nearly) synchronous with the orbital period (15.8d) of its satellite, Dysnomia. In this letter we present new light curve data of Eris, taken with ~1-2m-class ground based telescopes, and with the TESS and Gaia space telescopes. TESS data could not provide a well-defined light curve period, but could constrain light curve variations to a maximum possible light curve amplitude of dm<=0.03mag (1-sigma) for P<=24h periods. Both the combined ground-based data and the Gaia measurements unambiguously point to a light curve period equal to the orbital period of Dysnomia, P=15.8d, with a light curve amplitude of dm~0.03mag, i.e. the rotation of Eris is tidally locked. Assuming that Dysnomia has a collisional origin, calculations with a simple tidal evolution model show that Dysnomia has to be relatively massive (mass ratio of q=0.01-0.03) and large (radius of R_s_>=300km) to slow down Eris to synchronized rotation. These simulations also indicate that - assuming tidal parameters usually considered for transneptunian objects - the density of Dysnomia should be 1.8-2.4g/cm^3^, an exceptionally high value among similarly sized transneptunian objects, putting important constraints on the formation conditions., Collected photometry data from Gaia space observatory, TESS and from ground based telescopes, e.g. MPG 2.2m (GROND), La Hita 0.77m, CA2.2 (CAFOS2.2) and 1.5m telescope at Observatorio de Sierra Nevada., Financial support from the Severo Ochoa grant CEX2021-001131-S funded by MCIN/AEI/ 10.13039/501100011033, No

We report the first results of a high-redshift (z>~5) quasar survey using the Dark Energy Spectroscopic Instrument (DESI). As a DESI secondary target program, this survey is designed to carry out a systematic search and investigation of quasars at 4.8=5, more than one-third of existing quasars previously published at this redshift. The observations so far result in an average success rate of 23% at z>4.7. The current spectral data set has already allowed analysis of interesting individual objects (e.g., quasars with damped Ly{alpha} absorbers and broad absorption line features), and statistical analysis will follow the survey's completion. A set of science projects will be carried out leveraging this program, including quasar luminosity function, quasar clustering, intergalactic medium, quasar spectral properties, intervening absorbers, and properties of early supermassive black holes. Additionally, a sample of 38 new quasars at z~3.8-5.7 discovered from a pilot survey in the DESI SV1 is also published in this paper., The selected z~4.8-6.8 quasar candidates are mainly observed as dark-time targets in the Dark Energy Spectroscopic Instrument (DESI) main survey, which started on 2021-May-14. A minor part (1.6%) of candidates were observed during the DESI 1% survey (SV3; in 2021 April) and the DESI SV1 (before 2021 April 4; for 27 targets overlapped with the SV1 selection)., Financial support from the Severo Ochoa grant CEX2021-001131-S funded by MCIN/AEI/ 10.13039/501100011033, No