A5001815791- Stellar, planetary, and galactic studies
- Astrophysics and Star Formation Studies
- Astronomy and Astrophysical Research
- Astronomical Observations and Instrumentation
- Galaxies: Formation, Evolution, Phenomena
- Astro and Planetary Science
- Adaptive optics and wavefront sensing
- Gamma-ray bursts and supernovae
- Astrophysical Phenomena and Observations
- Geography and Environmental Studies in Latin America
- History and Developments in Astronomy
- Business, Education, Mathematics Research
- Scientific Research and Discoveries
- Atmospheric Ozone and Climate
- Calibration and Measurement Techniques
- Spectroscopy and Laser Applications
- Astronomical and nuclear sciences
- GNSS positioning and interference
- Electromagnetic Simulation and Numerical Methods
- Historical and Architectural Studies
- Impact of Light on Environment and Health
- History and advancements in chemistry
- Polish socio-economic development
- Geological and Tectonic Studies in Latin America
- Aerospace Engineering and Energy Systems
Universidad Nacional de La Plata
2015-2025
Consejo Nacional de Investigaciones Científicas y Técnicas
2016-2025
Instituto de Astrofísica de La Plata
2014-2024
Instituto de Ciencias Astronómicas, de la Tierra y del Espacio
2011
Osservatorio Astronomico di Padova
2003-2006
University of Padua
2003-2006
Centro Científico Tecnológico - Tucumán
2002
Argentine National Observatory
2000
Context. The ESO public survey VISTA variables in the Vía Láctea (VVV) started 2010. VVV targets 562 sq. deg Galactic bulge and an adjacent plane region is expected to run for about five years.
VISTA Variables in the V\'{\i}a L\'actea (VVV) is one of six ESO Public Surveys operating on new 4-meter Visible and Infrared Survey Telescope for Astronomy (VISTA). VVV scanning Milky Way bulge an adjacent section disk, where star formation activity high. One principal goals to find clusters different ages. In order trace early epochs cluster we concentrated our search directions those known regions, masers, radio, infrared sources. The disk area covered by was visually inspected using...
By using six new determined mid-eclipse times together with those collected from the literature, we found that Observed-Calculated (O-C) curve of RR Cae shows a cyclic change period 11.9 years and an amplitude 14.3s, while it undergoes upward parabolic variation (revealing long-term increase at rate dP/dt =+4.18(+-0.20)x10^(-12). The was analyzed for light-travel time effect arises gravitational influence third companion. mass body to be M_3*sin i' = 4.2(+-0.4) M_{Jup} suggesting is...
We combine optical and radio observations to trace the spiral structure in third quadrant of Milky Way. The consist a large sample young open clusters associations, whereas survey nearby distant clouds observed CO. Both samples are largest ones thus far presented literature. use this unique material analyze behavior interstellar extinction detailed Galactic (TGQ).We find that outer (Cygnus) grand design arm is traced by stellar CO components, while Perseus solely possibly being disrupted...
With the discovery of Sagittarius dwarf spheroidal (Ibata et al. 1994), a galaxy caught in process merging with Milky Way, hunt for other such accretion events has become very active field astrophysical research. The identification stellar ring-like structure Monoceros, spanning more than 100 degrees (Newberg 2002), and detection an overdensity stars direction constellation Canis Major (CMa, Martin 2004), apparently associated to ring, led widespread belief that second being cannibalised by...
Four newest CCD eclipse timings of the white dwarf for polar UZ Fornacis and Six updated mid-eclipse times SW Sex type nova-like V348 Puppis are obtained. The detailed O-C analyses both CVs inside period gap made. Orbital increases at a rate $2.63(\pm0.58)\times10^{-11} s\;s^{-1}$ $5.8(\pm1.9)\times10^{-12} Puppis, respectively, discovered in their new diagrams. However, conservative mass transfer from secondary to massive cannot explain observed orbital CVs, which regarded as part...
ABSTRACT This study focuses on the open cluster NGC 6834. Despite being well-known, its primary parameters show considerable variation. As an intermediate-age (50–80 million years), it is expected to host a prominent population of B-type stars, including numerous Be stars. Fifteen variable stars have already been identified in vicinity cluster, with four confirmed as through spectroscopic observations. Our spectrophotometric analysis aims better understand general and specific properties...
Context. The ESO Public Survey “VISTA Variables in the Vía Láctea” (VVV) provides deep multi-epoch infrared observations for unprecedented 562 sq. degrees of Galactic bulge, and adjacent regions disk.
Deep and extensive CCD photometric observations $UBV(RI)_{C}H_{\alpha}$ were carried out in the area of open cluster NGC 3293. The new data set allows to see entire sequence down $M_{V} \approx +4.5$, revealing that stars with < -2$ are evolving off main sequence; $-2 M_{V} +2$ located on > placed above it. According our analysis, distance is $d = 2750 \pm 250 pc$ ($V_{0}-M_{V} 12.2 0.2$) its nuclear age $8 1 Myr$. 3293 contains an important fraction pre--main (PMS) distributed along a...
We report the detection of a young stellar population (≤100 Myr) in background nine open clusters belonging to homogenous sample 30 star third Galactic quadrant (at 217° ≤ l 260°). Deep and accurate UBVRI photometry allows us measure model-independent age distance for with high confidence. This is exactly same (the blue plume) recently detected three intermediate-age suggested be ≤1-2 Gyr old Canis Major (CMa) overdensity (Bellazzini et al.; Martínez-Delgado al.). However, we find that those...
Context: The ESO Public Survey "VISTA Variables in the V\'ia L\'actea" (VVV) provides deep multi-epoch infrared observations for an unprecedented 562 sq. degrees of Galactic bulge, and adjacent regions disk. In this survey nearly 150 new open clusters cluster candidates have been discovered. Aims: This is second a series papers about young, massive observed using VVV survey. We present first study six recently discovered clusters. These contain at least one newly Wolf-Rayet (WR) star....
view Abstract Citations (62) References (21) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Sudden Luminous Blue Variable--Like Behavior of the Wolf-Rayet Binary System HD 5980 in Small Magellanic Cloud Barba, Rodolfo H. ; Niemela, Virpi S. Baume, Gustavo Vazquez, R. A. We report a sudden outburst-like behavior WR binary system SMC, as disclosed by spectroscopic and photometric observations performed 1994 October November. Our spectra show that type spectrum...
We present the first results of a ground-based program to determine proper motion Magellanic Clouds (MCs) relative background quasars (QSO), being carried out using Iréneé du Pont 2.5 m telescope at Las Campanas Observatory, Chile. Eleven QSO fields have been targeted in Small Cloud (SMC) over time base six years, and with seven epochs observation. One quasar field was Large (LMC), five The shorter case LMC is compensated by much larger amount high-quality astrometry frames that could be...
CCD UBVI photometry in the field of open cluster NGC 6231 was obtained for 1060 stars down to mag. Memberships, reddening, distance and age this were investigated. Its lower sequence displays a notorious bend at mag followed by high number faint showing large magnitude spread constant colour. This distribution does not seem be produced mere accumulation seen direction but real star excess zone. The evidence suggests these are serious candidates members caught their way towards ZAMS. Fitting...
A new X-ray, UBVRIc, and JHKs study of the young cluster Westerlund 2 was undertaken to resolve discrepancies tied cluster's distance. Existing spectroscopic observations for bright members multi-band photometry imply a reddening relation toward described by EU − B/EB V = 0.63 + 0.02EB V. Variable-extinction analyses nearby IC 2581 based upon distance moduli ZAMS fitting yield values RV AV/EB 3.88 ± 0.18 3.77 0.19, respectively, confirm prior assertions that anomalous interstellar extinction...
We present optical ($UBVI_C$) observations of a rich and complex field in the Galactic plane towards $l \sim 305^{\circ}$ $b 0^{\circ}$. Our analysis reveals significantly high interstellar absorbtion ($A_V 10$) an abnormal extinction law this line sight. Availing considerable number color combinations, photometric diagrams allow us to derive new estimates fundamental parameters two open clusters Danks~1 Danks~2. Due derived reddening sight, both appear much closer (to Sun) than previously...
Context: The Ara OB1a association is a nearby complex in the fourth Galactic quadrant where number of young/embedded star clusters are projected close to more evolved, intermediate age clusters. It also rich interstellar matter, and contains evidence interplay between massive stars their surrounding medium, such as rim HII region NGC 6188. Aims: We provide robust estimates fundamental parameters (age distance) two most prominent stellar clusters, 6167 6193, that may be used basis for studing...
Only a small number of galactic open clusters survives for longer than few hundred million years. Longer lifetimes are routinely explained in term larger initial masses, particularly quiet orbits, and off-plane birth-places. We derive this work the actual mass NGC 4337, one Milky Way inner disk that managed to survive about 1.5 Gyr. its two different ways. First, we exploit an unpublished photometric data set UBVI passbands estimate -using star counts- cluster luminosity profile, function,...
CCD BVI photometry of the faint open clusters Berkeley~73, Berkeley~75 and Berkeley~25 are presented. The two latter previously unstudied to our knowledge. While Berkeley~73 is found be intermediate-age (about 1.5 Gyr old), old clusters, with ages larger than 3.0 Gyr. We provide also estimates size. Very interestingly, all these turn out lie far away from Galactic Center, at $R_{GC} \geq$ 16 kpc, quite high onto plane, $|Z_{\odot}| \geq 1.5$ kpc. They therefore important targets probe...
The color-magnitude diagram (CMD) of the intermediate-age Large Magellanic Cloud (LMC) star cluster NGC 2154 and its adjacent field, has been analyzed using Padova stellar models to determine cluster's fundamental parameters Star Formation History (SFH). Deep $BR$ CCD photometry, together with synthetic CMDs Integrated Luminosity Functions (ILFs), allowed us infer that experienced an extended formation period about 1.2 Gyrs, which began approximately 2.3 Gyr ended 1.1 ago. physical reality...
Aiming to improve the knowledge of Galactic structure in second quadrant, we selected 10 young open clusters from a sample more than 200 covered by SDSS. Our study was based on photometric data set provided SDSS and APASS visible 2MASS WISE infrared. We also carried out spectroscopic observations with GMOS/GEMINI made use information available literature. The analysis performed suite tools developed us systematically determine main parameters studied clusters, identify possible...
Aims. The purpose of this work is to understand the global characteristics stellar populations in NGC 300. In particular, we focused our attention on searching young star groups and study their hierarchical organization. proximity orientation Sculptor Group galaxy make it an ideal candidate for study.
We present CCD broad band photometric observations in the fields of Third Galactic Quadrant open clusters NGC 2580 and 2588 (V(I)C UBV(RI)C respectively). From analysis our data we found that is located at a distance about 4 kpc its age close to 160 Myr. As for 2588, it placed 5 from Sun 450 Myr old. This means belongs extension Perseus arm, whereas closer local arm structure. The luminosity functions (LFs) have been constructed both down together with their initial mass (IMFs) stars masses...