A5081861417- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Gamma-ray bursts and supernovae
- Astronomical Observations and Instrumentation
- Astro and Planetary Science
- Fluoride Effects and Removal
- Calibration and Measurement Techniques
- Planetary Science and Exploration
- Astrophysical Phenomena and Observations
- Heavy metals in environment
- Mercury impact and mitigation studies
- Astrophysics and Cosmic Phenomena
- Inorganic Fluorides and Related Compounds
- Space exploration and regulation
- Heavy Metal Exposure and Toxicity
- Distributed and Parallel Computing Systems
- Maritime Ports and Logistics
- Galaxies: Formation, Evolution, Phenomena
- Pulsars and Gravitational Waves Research
- Space Satellite Systems and Control
- Space Science and Extraterrestrial Life
- Adaptive optics and wavefront sensing
- Layered Double Hydroxides Synthesis and Applications
- Groundwater and Isotope Geochemistry
Universidad de La Laguna
2001-2024
Instituto de Astrofísica de Canarias
2020-2024
National Astronomical Observatory of Japan
2024
Isaac Newton Group
2019-2023
Nordic Optical Telescope
2020
European Space Astronomy Centre
2019
Centro de Astrobiología
2019
Context. The lack of high-precision long-term continuous photometric data for large samples stars has impeded the large-scale exploration pulsational variability in OB star regime. As a result, candidates in-depth asteroseismic modelling have remained limited to few dozen dwarfs. TESS nominal space mission surveyed southern sky, including parts galactic plane, yielding across at least 27 d hundreds stars. Aims. We aim couple sky with ground-based spectroscopy study two dimensions, mass and...
Abstract During the Zwicky Transient Facility (ZTF) Phase I operations, 78 hydrogen-poor superluminous supernovae (SLSNe-I) were discovered in less than 3 yr, constituting largest sample from a single survey. This paper (Paper I) presents data, including optical/UV light curves and classification spectra, while Paper II this series will focus on detailed analysis of modeling. Our photometry is primarily taken by ZTF g , r i bands, with additional data other ground-based facilities Swift. The...
The INT Galactic Plane Survey (IGAPS) is the merger of optical photometric surveys, IPHAS and UVEX, based on data from Isaac Newton Telescope (INT) obtained between 2003 2018. Here, we present IGAPS point source catalogue. It contains 295.4 million rows providing photometry in filters, i, r, narrow-band Halpha, g U_RGO. footprint fills coordinate range, |b| < 5deg 30deg l 215deg. A uniform calibration, referred to Pan-STARRS system, applied g, r while Halpha calibration linked then...
LB-1 has recently been proposed to be a binary system at 4 kpc consisting of B star 8 Msol and massive stellar black hole 70 Msol. This finding challenges our current theories evolution formation BHs solar metallicity. Our objective is derive the effective temperature, surface gravity chemical composition B-type component in order determine its nature evolutionary status and, indirectly, constrain mass BH. We use non-LTE atmosphere code FASTWIND analyse new archival high resolution data....
Blue supergiants (BSGs) are important objects to study the intermediate phases of massive star evolution, helping constrain evolutionary models. However, lack a holistic statistically significant and unbiased sample these makes several long-standing questions about their nature remain unsolved. The present other upcoming papers IACOB series focused in studying - from pure empirical point view 500 Galactic O9 B9 stars with luminosity classes I II (plus 250 late O- early B-type III, IV V)...
Context . Blue supergiants (BSGs) are key objects for understanding the evolution of massive stars, which play a crucial role in galaxies. However, discrepancies between theoretical predictions and empirical observations have opened up important questions yet to be answered. Studying statistically significant unbiased samples these can help improve situation. Aims We perform homogeneous comprehensive quantitative spectroscopic analysis large sample Galactic luminous blue stars (a majority...
Massive stars play a very important role in many astrophysical fields. Yet, some fundamental aspects of their evolution remain poorly constrained. In this regard, there is an open debate on the width main-sequence (MS) phase. We aim to create updated Hertzsprung-Russell (HR) diagram that includes volume-limited and statistically significant sample massive stars. Our goal use investigate extension MS, including information about projected rotational velocities ($v\sin i$) spectroscopic binary...
Massive stars play a very important role in many astrophysical fields. Despite their scarcity with respect to less-massive counterparts, influence on the chemo-dynamical evolution of galaxies is substantial. Yet, some fundamental aspects remain poorly constrained. In this regard, there an open debate width main-sequence (MS) phase, which spend most lifetimes. We aim create updated Hertzsprung-Russell (HR) diagram that includes volume-limited and statistically significant sample massive...
Context. We need to understand the spin evolution of massive stars compute their internal rotationally induced mixing processes, isolate effects close binary evolution, and predict rotation rates white dwarfs, neutron black holes. Aims. discuss spindown main sequence imposed by stellar winds. Methods. use detailed grids single star evolutionary models distribution surface rotational velocities core-hydrogen burning Galactic as function mass state. then compare properties our synthetic...
Estimating the risk associated with dietary intake of heavy metals by consumers is a vital and integral part regulatory processes. The assessment exposure to mercury shown in this paper has been performed means study on whole diet. Total (Hg) levels were determined cold vapour atomic absorption spectrometry (AAS) 420 samples regularly consumed food drink. total Hg concentrations measured different groups ranged from non-detectable 119 µg kg−1 w/w. fish group had highest Hg. All regulated...
Context . With the advent of large spectroscopic surveys, automated stellar parameter determination has become commonplace. Nevertheless, spectral classification still offers a quick and useful alternative for obtaining estimates samples spectra varying quality. Aims We present new atlas covering B-type range, with intention providing detailed criteria valid modern improving grid reliable standards. This will be used in future works to provide beyond classical range addressing, particular,...
Context. Only a few open clusters are as important for the study of stellar and substellar objects, their formation evolution, young σ Orionis cluster. However, complete spectroscopic characterisation its whole population is still missing. Aims. We filled most that gap with large astrometric survey targets towards Orionis. Eventually, it will be one lowest proportion interlopers largest confirmed cluster members known uncontrovertible youth features. Methods. acquired 317 low-resolution...
The Perseus OB1 association hosts one of the most populous groupings blue and red supergiants (Sgs) in Galaxy. We discuss whether massive O-type blue/red Sg stars located Per region are members same population examine their binary runaway status. gathered a total 405 high-resolution spectra for 88 suitable candidates around 4.5 deg from center association, compiled Gaia DR2 astrometry all them. This was used to investigate membership identify stars. By obtaining high-precision radial...
LB-1 has variously been proposed as either an X-ray dim B-type star plus black hole (B+BH) binary, or a Be inflated stripped (Be+Bstr) binary. The Space Telescope Imaging Spectrograph (STIS) on board HST was used to obtain flux-calibrated spectrum that is compared with non-LTE spectral energy distributions (SED) and line profiles for the models. Hubble data, together Gaia EDR3 parallax, provide tight constraints properties stellar luminosities of system. In case Be+Bstr model we adopt...
ABSTRACT We present the first optical study of supernova remnant (SNR) G7.7–3.7, with aim determining its evolutionary phase since it has been suggested to be SN 386 AD. obtained narrow-band images in filters H α + [N ii], β, [O iii], [S ii] that revealed faint emission southern region SNR consisting two filaments elongated east–west direction aligned X-ray emitting remnant. The were seen iii] and marginally images, a non-detection β. Long-slit spectroscopy three regions along one filament...
The properties of blue supergiants are key for constraining the end main sequence (MS) massive stars. Whether observed drop in relative number fast-rotating stars below ≈21 kK is due to enhanced mass-loss rates at location bistability jump, or result MS still debated. Here, we combine newly derived estimates photospheric and wind parameters with Gaia distances terminal velocities from literature obtain upper limits on a sample 116 Galactic luminous supergiants. parameter space covered by...
Abstract We study the 2018 Martian global dust storm (GDS 2018) over Southern Polar Region using images obtained by Visual Monitoring Camera (VMC) on board Mars Express (MEx) during June and July 2018. Dust penetrated into polar cap region but never covered completely, its spatial distribution was nonhomogeneous rapidly changing. However, we detected long narrow aerosol curved arcs with a length of ~ 2,000–3,000 km traversing part crossing terminator nightside. Tracking discrete clouds...
Here we explore the efficiency and fidelity of a purely astrometric selection quasars as point sources with zero proper motions in Gaia data release 2 (DR2). We have built complete candidate sample including 104 -DR2 sources, which are brighter than 20th magnitude G -band within one degree north Galactic pole (NGP); all them that consistent σ uncertainty. In addition to pre-existing spectra, secured long-slit spectroscopy remaining candidates find stationary field can be classified either...
Automated analysis of Gaia astrometric data has led to the discovery many new high-quality open cluster candidates. With a good determination their parameters, these objects become excellent tools investigate properties our Galaxy. We explore whether young clusters can be readily identified from alone by studying colour-magnitude diagrams. also want compare results traditional with those automated methods. selected three candidates UBC catalogue, ranging well-populated object well-defined...