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Context. The ESO public survey VISTA Variables in the Vía Láctea (VVV) surveyed the inner Galactic bulge and the adjacent southern Galactic disk from 2009−2015. Upon its conclusion, the complementary VVV eXtended (VVVX) survey has expanded both the temporal as well as spatial coverage of the original VVV area, widening it from 562 to 1700 sq. deg., as well as providing additional epochs in JHKs filters from 2016−2023. Aims. With the completion of VVVX observations during the first semester of 2023, we present here the observing strategy, a description of data quality and access, and the legacy of VVVX. Methods. VVVX took ∼ 2000 hours, covering about 4% of the sky in the bulge and southern disk. VVVX covered most of the gaps left between the VVV and the VISTA Hemisphere Survey (VHS) areas and extended the VVV time baseline in the obscured regions affected by high extinction and hence hidden from optical observations. Results. VVVX provides a deep JHKs catalogue of & 1.5 × 109 point sources, as well as a Ks band catalogue of ∼ 107 variable sources. Within the existing VVV area, we produced a 5D map of the surveyed region by combining positions, distances, and proper motions of well-understood distance indicators such as red clump stars, RR Lyrae, and Cepheid variables. Conclusions. In March 2023 we successfully finished the VVVX survey observations that started in 2016, an accomplishment for ESO Paranal Observatory upon 4200 hours of observations for VVV+VVVX. The VVV+VVVX catalogues complement those from the Gaia mission at low Galactic latitudes and provide spectroscopic targets for the forthcoming ESO high-multiplex spectrographs MOONS and 4MOST.

Context. The ESO public survey VISTA Variables in the Vía Láctea (VVV) surveyed the inner Galactic bulge and the adjacent southern Galactic disk from 2009−2015. Upon its conclusion, the complementary VVV eXtended (VVVX) survey has expanded both the temporal as well as spatial coverage of the original VVV area, widening it from 562 to 1700 sq. deg., as well as providing additional epochs in JHKs filters from 2016−2023. Aims. With the completion of VVVX observations during the first semester of 2023, we present here the observing strategy, a description of data quality and access, and the legacy of VVVX. Methods. VVVX took ∼ 2000 hours, covering about 4% of the sky in the bulge and southern disk. VVVX covered most of the gaps left between the VVV and the VISTA Hemisphere Survey (VHS) areas and extended the VVV time baseline in the obscured regions affected by high extinction and hence hidden from optical observations. Results. VVVX provides a deep JHKs catalogue of & 1.5 × 109 point sources, as well as a Ks band catalogue of ∼ 107 variable sources. Within the existing VVV area, we produced a 5D map of the surveyed region by combining positions, distances, and proper motions of well-understood distance indicators such as red clump stars, RR Lyrae, and Cepheid variables. Conclusions. In March 2023 we successfully finished the VVVX survey observations that started in 2016, an accomplishment for ESO Paranal Observatory upon 4200 hours of observations for VVV+VVVX. The VVV+VVVX catalogues complement those from the Gaia mission at low Galactic latitudes and provide spectroscopic targets for the forthcoming ESO high-multiplex spectrographs MOONS and 4MOST.

Context. The ESO public survey VISTA Variables in the Vía Láctea (VVV) surveyed the inner Galactic bulge and the adjacent southern Galactic disk from 2009−2015. Upon its conclusion, the complementary VVV eXtended (VVVX) survey has expanded both the temporal as well as spatial coverage of the original VVV area, widening it from 562 to 1700 sq. deg., as well as providing additional epochs in JHKs filters from 2016−2023. Aims. With the completion of VVVX observations during the first semester of 2023, we present here the observing strategy, a description of data quality and access, and the legacy of VVVX. Methods. VVVX took ∼ 2000 hours, covering about 4% of the sky in the bulge and southern disk. VVVX covered most of the gaps left between the VVV and the VISTA Hemisphere Survey (VHS) areas and extended the VVV time baseline in the obscured regions affected by high extinction and hence hidden from optical observations. Results. VVVX provides a deep JHKs catalogue of & 1.5 × 109 point sources, as well as a Ks band catalogue of ∼ 107 variable sources. Within the existing VVV area, we produced a 5D map of the surveyed region by combining positions, distances, and proper motions of well-understood distance indicators such as red clump stars, RR Lyrae, and Cepheid variables. Conclusions. In March 2023 we successfully finished the VVVX survey observations that started in 2016, an accomplishment for ESO Paranal Observatory upon 4200 hours of observations for VVV+VVVX. The VVV+VVVX catalogues complement those from the Gaia mission at low Galactic latitudes and provide spectroscopic targets for the forthcoming ESO high-multiplex spectrographs MOONS and 4MOST.

With the advent of large-scale photometric surveys of the sky, modern science witnesses the dawn of big data astronomy, where automatic handling and discovery are paramount. In this context, classification tasks are among the key capabilities a data reduction pipeline must possess in order to compile reliable datasets, to accomplish data processing with an efficiency level impossible to achieve by means of detailed processing and human intervention. The VISTA Variables of the V\'ia L\'actea Survey, in the southern part of the Galactic disc, comprises multi-epoch photometric data necessary for the potential discovery of variable objects, including eclipsing binary systems (EBs). In this study we use a recently published catalogue of one hundred EBs, classified by fine-tuning theoretical models according to contact, detached or semi-detached classes belonging to the tile d040 of the VVV. We describe the method implemented to obtain a supervised machine learning model, capable of classifying EBs using information extracted from the light curves of variable object candidates in the phase space from tile d078. We also discuss the efficiency of the models, the relative importance of the features and the future prospects to construct an extensive database of EBs in the VVV survey., Comment: 11 pages, 9 figures, , accepted in MNRAS

We aim to analyze the chemical evolution of the Small Magellanic Cloud adding 12 additional clusters to our existing sample having accurate and homogeneously derived metallicities. We are particularly interested in seeing if there is any correlation between age and metallicity for the different structural components to which the clusters belong. Spectroscopic metallicities of red giant stars are derived from the measurement of the equivalent width of the near-IR calcium triplet lines. Cluster membership analysis was carried out using criteria that include radial velocities, metallicities, proper motions and distance from the cluster center. The mean cluster radial velocity and metallicity were determined with a typical error of 2.1 km/s and 0.03 dex, respectively. We added this information to that available in the literature for other clusters studied with the same method, compiling a final sample of 48 clusters with metallicities homogeneously determined. Clusters of the final sample are distributed in an area of ~ 70 deg^2 and cover an age range from 0.4 Gyr to 10.5 Gyr. The metallicity distribution of our new cluster sample shows a lower probability of being bimodal than suggested in previous studies. The separate chemical analysis of clusters in the six components (Main Body, Counter-Bridge, West Halo, Wing/Bridge, Northern Bridge and Southern Bridge) shows that only clusters belonging to the Northern Bridge appear to trace a V-Shape, showing a clear inversion of the metallicity gradient in the outer regions. There is a suggestion of a metallicity gradient in the West Halo, similar to that previously found for field stars. It presents, however, a very large uncertainty. Also, clusters belonging to the West Halo, Wing/Bridge and Southern Bridge exhibit a well-defined age-metallicity relation with relatively little scatter in abundance at fixed age compared to other regions., Comment: 16 pages, 18 figures,Accepted for publication in A&A

We aim to analyze the chemical evolution of the Small Magellanic Cloud adding 12 additional clusters to our existing sample having accurate and homogeneously derived metallicities. We are particularly interested in seeing if there is any correlation between age and metallicity for the different structural components to which the clusters belong. Spectroscopic metallicities of red giant stars are derived from the measurement of the equivalent width of the near-IR calcium triplet lines. Cluster membership analysis was carried out using criteria that include radial velocities, metallicities, proper motions and distance from the cluster center. The mean cluster radial velocity and metallicity were determined with a typical error of 2.1 km/s and 0.03 dex, respectively. We added this information to that available in the literature for other clusters studied with the same method, compiling a final sample of 48 clusters with metallicities homogeneously determined. Clusters of the final sample are distributed in an area of ~ 70 deg^2 and cover an age range from 0.4 Gyr to 10.5 Gyr. The metallicity distribution of our new cluster sample shows a lower probability of being bimodal than suggested in previous studies. The separate chemical analysis of clusters in the six components (Main Body, Counter-Bridge, West Halo, Wing/Bridge, Northern Bridge and Southern Bridge) shows that only clusters belonging to the Northern Bridge appear to trace a V-Shape, showing a clear inversion of the metallicity gradient in the outer regions. There is a suggestion of a metallicity gradient in the West Halo, similar to that previously found for field stars. It presents, however, a very large uncertainty. Also, clusters belonging to the West Halo, Wing/Bridge and Southern Bridge exhibit a well-defined age-metallicity relation with relatively little scatter in abundance at fixed age compared to other regions., Comment: 16 pages, 18 figures,Accepted for publication in A&A

(ABRIDGED) Recent near-IR surveys have uncovered a plethora of new globular cluster (GC) candidates towards the Milky Way bulge. These new candidates need to be confirmed as real GCs and properly characterised. We investigate the physical nature of FSR 1776. This object was originally classified as an intermediate-age open cluster and has recently been re-discovered independently and classified as a GC candidate (Minni 23). Firstly, we aim at confirming its GC nature; secondly we determine its physical parameters. The confirmation of the cluster existence is checked using the radial velocity (RV) distribution of a MUSE data cube centred at FSR 1776. The cluster parameters are derived from isochrone fitting to the RV-cleaned colour-magnitude diagrams (CMDs) from visible and near-infrared photometry. The predicted RV distribution for the FSR 1776 coordinates, considering only contributions from the bulge and disc field stars, is not enough to explain the observed MUSE RV distribution. The extra population (12\% of the sample) is FSR 1776 with an average RV of $-103.7\pm 0.4~{\rm km}\,{\rm s}^{-1}$. The CMDs reveal that it is 10$\pm$1~Gyr old and metal-rich, with [Fe/H]$_{phot}\approx + 0.2\pm$0.2, [Fe/H]$_{spec}=~+0.02\pm0.01~(\sigma~=~0.14$~dex), located at the bulge distance of 7.24$\pm$0.5~kpc with A$_{\rm V}$ $\approx$ 1.1~mag. The mean cluster proper motions are ($\langle\mu_{\alpha}\rangle,\langle\mu_{\delta}\rangle$) $=$ ($-2.3\pm1.1,-2.6\pm0.8$) ${\rm mas\, yr^{-1}}$.} FSR 1776 is an old GC located in the Galactic bulge with a super-solar metallicity, among the highest for a Galactic GC. This is consistent with predictions for the age-metallicity relation of the bulge, being FSR 1776 the probable missing link between typical GCs and the metal-rich bulge field. High-resolution spectroscopy of a larger field of view and deeper CMDs are now required for a full characterisation., Comment: 15 pages, 19 figures, accepted for publication in Astronomy & Astrophysics

Recent near-IR Surveys have discovered a number of new bulge globular cluster (GC) candidates that need to be further investigated. Our main objective is to use public data from the Gaia Mission, VVV, 2MASS and WISE in order to measure the physical parameters of Minni48, a new candidate GC located in the inner bulge of the Galaxy at l=359.35 deg, b=2.79 deg. Even though there is a bright foreground star contaminating the field, the cluster appears quite bright in near- and mid-IR images. We obtain deep decontaminated optical and near-IR colour-magnitude diagrams (CMDs) for this cluster. The heliocentric cluster distance is determined from the red clump (RC) and the red giant branch (RGB) tip magnitudes in the near-IR CMD, while the cluster metallicity is estimated from the RGB slope and the fit to theoretical isochrones. The GC size is found to be r = 6' +/- 1', while reddening and extinction values are E(J-Ks)=0.60 +/- 0.05 mag, A_G=3.23 +/- 0.10 mag, A_Ks=0.45 +/- 0.05 mag. The resulting mean Gaia proper motions are PMRA=-3.5 +/- 0.5 mas/yr, PMDEC=-6.0 +/- 0.5 mas/yr. The IR magnitude of the RC yields an accurate distance modulus estimate of (m-M)_0=14.61 mag, equivalent to a distance D=8.4 +/- 1.0 kpc. This is consistent with the optical distance estimate: (m-M)_0=14.67 mag, D=8.6 +/- 1.0 kpc, and with the RGB tip distance: (m-M)_0=14.45 mag, D=7.8 +/- 1.0 kpc. The derived metallicity is [Fe/H]=-0.20 +/- 0.30 dex. A good fit to the PARSEC stellar isochrones is obtained in all CMDs using Age = 10 +/- 2 Gyr. The total absolute magnitude of this GC is estimated to be M_Ks= -9.04 +/- 0.66 mag. Based on its position, kinematics, metallicity and age, we conclude that Minni48 is a genuine GC, similar to other well known metal-rich bulge GCs. It is located at a projected Galactocentric angular distance of 2.9 deg, equivalent to 0.4 kpc, being one of the closest GCs to the Galactic centre., Comment: 12 pages, 15 figures. Abridged abstract. Accepted for publication in the Astronomy & Astrophysics

(ABRIDGED) Recent near-IR surveys have uncovered a plethora of new globular cluster (GC) candidates towards the Milky Way bulge. These new candidates need to be confirmed as real GCs and properly characterised. We investigate the physical nature of FSR 1776. This object was originally classified as an intermediate-age open cluster and has recently been re-discovered independently and classified as a GC candidate (Minni 23). Firstly, we aim at confirming its GC nature; secondly we determine its physical parameters. The confirmation of the cluster existence is checked using the radial velocity (RV) distribution of a MUSE data cube centred at FSR 1776. The cluster parameters are derived from isochrone fitting to the RV-cleaned colour-magnitude diagrams (CMDs) from visible and near-infrared photometry. The predicted RV distribution for the FSR 1776 coordinates, considering only contributions from the bulge and disc field stars, is not enough to explain the observed MUSE RV distribution. The extra population (12\% of the sample) is FSR 1776 with an average RV of $-103.7\pm 0.4~{\rm km}\,{\rm s}^{-1}$. The CMDs reveal that it is 10$\pm$1~Gyr old and metal-rich, with [Fe/H]$_{phot}\approx + 0.2\pm$0.2, [Fe/H]$_{spec}=~+0.02\pm0.01~(\sigma~=~0.14$~dex), located at the bulge distance of 7.24$\pm$0.5~kpc with A$_{\rm V}$ $\approx$ 1.1~mag. The mean cluster proper motions are ($\langle\mu_{\alpha}\rangle,\langle\mu_{\delta}\rangle$) $=$ ($-2.3\pm1.1,-2.6\pm0.8$) ${\rm mas\, yr^{-1}}$.} FSR 1776 is an old GC located in the Galactic bulge with a super-solar metallicity, among the highest for a Galactic GC. This is consistent with predictions for the age-metallicity relation of the bulge, being FSR 1776 the probable missing link between typical GCs and the metal-rich bulge field. High-resolution spectroscopy of a larger field of view and deeper CMDs are now required for a full characterisation., Comment: 15 pages, 19 figures, accepted for publication in Astronomy & Astrophysics

Recent near-IR Surveys have discovered a number of new bulge globular cluster (GC) candidates that need to be further investigated. Our main objective is to use public data from the Gaia Mission, VVV, 2MASS and WISE in order to measure the physical parameters of Minni48, a new candidate GC located in the inner bulge of the Galaxy at l=359.35 deg, b=2.79 deg. Even though there is a bright foreground star contaminating the field, the cluster appears quite bright in near- and mid-IR images. We obtain deep decontaminated optical and near-IR colour-magnitude diagrams (CMDs) for this cluster. The heliocentric cluster distance is determined from the red clump (RC) and the red giant branch (RGB) tip magnitudes in the near-IR CMD, while the cluster metallicity is estimated from the RGB slope and the fit to theoretical isochrones. The GC size is found to be r = 6' +/- 1', while reddening and extinction values are E(J-Ks)=0.60 +/- 0.05 mag, A_G=3.23 +/- 0.10 mag, A_Ks=0.45 +/- 0.05 mag. The resulting mean Gaia proper motions are PMRA=-3.5 +/- 0.5 mas/yr, PMDEC=-6.0 +/- 0.5 mas/yr. The IR magnitude of the RC yields an accurate distance modulus estimate of (m-M)_0=14.61 mag, equivalent to a distance D=8.4 +/- 1.0 kpc. This is consistent with the optical distance estimate: (m-M)_0=14.67 mag, D=8.6 +/- 1.0 kpc, and with the RGB tip distance: (m-M)_0=14.45 mag, D=7.8 +/- 1.0 kpc. The derived metallicity is [Fe/H]=-0.20 +/- 0.30 dex. A good fit to the PARSEC stellar isochrones is obtained in all CMDs using Age = 10 +/- 2 Gyr. The total absolute magnitude of this GC is estimated to be M_Ks= -9.04 +/- 0.66 mag. Based on its position, kinematics, metallicity and age, we conclude that Minni48 is a genuine GC, similar to other well known metal-rich bulge GCs. It is located at a projected Galactocentric angular distance of 2.9 deg, equivalent to 0.4 kpc, being one of the closest GCs to the Galactic centre., Comment: 12 pages, 15 figures. Abridged abstract. Accepted for publication in the Astronomy & Astrophysics

Context. Globular clusters (GCs) are witnesses of the past accretion events onto the Milky Way (MW). In particular, the GCs of the Sagittarius (Sgr) dwarf galaxy are important probes of an on-going merger. Aims. Our main goal is to search for new GC members of this dwarf galaxy using the VISTA Variables in the Via Lactea Extended Survey (VVVX) near-infrared database combined with the Gaia Early Data Release 3 (EDR3) optical database. Methods. We investigated all VVVX-enabled discoveries of GC candidates in a region covering about 180 sq. deg. toward the bulge and the Sgr dwarf galaxy. We used multiband point-spread function photometry to obtain deep color-magnitude diagrams (CMDs) and luminosity functions (LFs) for all GC candidates, complemented by accurate Gaia-EDR3 proper motions (PMs) to select Sgr members and variability information to select RR Lyrae which are potential GC members. Results. After applying a strict PM cut to discard foreground bulge and disk stars, the CMDs and LFs for some of the GC candidates exhibit well defined red giant branches and red clump giant star peaks. We selected the best Sgr GCs, estimating their distances, reddenings, and associated RR Lyrae. Conclusions. We discover 12 new Sgr GC members, more than doubling the number of GCs known in this dwarf galaxy. In addition, there are 11 other GC candidates identified that are uncertain, awaiting better data for confirmation., Comment: 12 pages, 6 Figures

We present the first results obtained from an extensive study of eclipsing binary (EB) system candidates recently detected in the VISTA Variables in the V\'ia L\'actea (VVV) near-infrated (NIR) Survey. We analyze the VVV tile d040 in the southern part of the Galactic disc wherein the interstellar reddening is comparatively low, which makes it possible to detect hundreds of new eclipsing binary candidates. We present here the light curves and the determination of the geometric and physical parameters of the best candidates found in this "NIR window", including 37 contact, 50 detached and 13 semi-detached eclipsing binary systems. We infer that the studied systems have an average of the $K_s$ amplitudes of $0.8$ mag and a median period of 1.22 days where, in general, contact binaries have shorter periods. Using the "Physics Of Eclipsing Binaries" (PHOEBE) interactive interface, which is based on the Wilson and Devinney code, we find that the studied systems have low eccentricities. The studied EBs present mean values of about 5700 K and 4900 K for the $T_1$ and $T_2$ components, respectively. The mean mass-ratio ($q$) for the contact EB stars is $\sim$ 0.44. This new Galactic disc sample is a first approach to the massive study of NIR EB systems., Comment: 14 pages, 10 figures. Accepted for publication in PASA

Milky Way globular clusters (MW GCs) are difficult to identify at low Galactic latitudes because of high differential extinction and heavy star crowding. The new deep near-IR images and photometry from the VISTA Variables in the Via L\'actea Extended Survey (VVVX) allow us to chart previously unexplored regions. Our long term aim is to complete the census of MW GCs. The immediate goals are to estimate the astrophysical parameters, measuring their reddenings, extinctions, distances, total luminosities, proper motions, sizes, metallicities and ages. We use the near-IR VVVX survey database, in combination with Gaia DR2 optical photometry, and with the Two Micron All Sky Survey (2MASS) photometry. We report the detection of a heretofore unknown Galactic Globular Cluster at $RA =$ 14:09:00.0; $DEC=-$65:37:12 (J2000). We calculate a reddening of $E(J-K_s)=(0.3\pm 0.03)$ mag and an extinction of $A_{K_s}=(0.15\pm 0.01)$ mag for this new GC. Its distance modulus and corresponding distance were measured as $(m-M)=(15.93\pm0.03)$ mag and $D=(15.5\pm1.0)$ kpc, respectively. We estimate the metallicity and age by comparison with known GCs and by fitting PARSEC and Dartmouth isochrones, finding $[Fe/H]=(-0.70\pm0.2)$ dex and $t=(11.0\pm1.0)$ Gyr. The mean GC PMs from Gaia are $\mu_{\alpha^\ast}=(-4.68 \pm 0.47 )$ mas $yr^{-1}$ and $\mu_{\delta}=(-1.34 \pm 0.45)$ mas $yr^{-1}$. The total luminosity of our cluster is estimated to be $M_{Ks}=(-7.76\pm 0.5)$ mag. We have found a new low-luminosity, old and metal-rich globular cluster, situated in the far side of the Galactic disk, at $R_{G}=11.2$ kpc from the Galactic centre, and at $z=1.0$ kpc below the plane. Interestingly, the location, metallicity and age of this globular cluster are coincident with the Monoceros Ring (MRi) structure.

37 potential members of the red-giant branches of NGC 6192, NGC 6208 and NGC 6268 were observed in the UBV system, while 22 of them were also observed in the DDO system. The observations were made at La Silla and Cerro Tololo Inter-American observatories (Chile), using pulse-counting photoelectric photometers. Coravel radial velocities (RVs) were obtained at La Silla for 24 red giant candidates in the three clusters. Five stars of NGC 6192 have RVs in the narrow range -8.8 km/s < VR < -6.4 km/s, including two new spectroscopic binaries (SBs). Three stars of NGC 6208 - including a new SB - and three stars of NGC 6268 show similar RVs so that their physical membership to NGC 6208 and NGC 6268, respectively, is highly probable. Mean radial velocities are: -7.7 ± 0.38 km/s (NGC 6192), -32.21 ± 0.28 km/s (NGC 6208) and -15.11 ± 0.08 km/s (NGC 6268). We have also derived the following mean E(B-V) values from Janes (1977) iterative method: 0.63 ± 0.02 (NGC 6192), 0.31 ± 0.02 (NGC 6208) and 0.43 ± 0.02 (NGC 6268)

We obtained spectra of red giants in 15 Small Magellanic Cloud (SMC) clusters in the region of the CaII lines with FORS2 on the Very Large Telescope (VLT). We determined the mean metallicity and radial velocity with mean errors of 0.05 dex and 2.6 km/s, respectively, from a mean of 6.5 members per cluster. One cluster (B113) was too young for a reliable metallicity determination and was excluded from the sample. We combined the sample studied here with 15 clusters previously studied by us using the same technique, and with 7 clusters whose metallicities determined by other authors are on a scale similar to ours. This compilation of 36 clusters is the largest SMC cluster sample currently available with accurate and homogeneously determined metallicities. We found a high probability that the metallicity distribution is bimodal, with potential peaks at -1.1 and -0.8 dex. Our data show no strong evidence of a metallicity gradient in the SMC clusters, somewhat at odds with recent evidence from CaT spectra of a large sample of field stars Dobbie et al. (2014). This may be revealing possible differences in the chemical history of clusters and field stars. Our clusters show a significant dispersion of metallicities, whatever age is considered, which could be reflecting the lack of a unique AMR in this galaxy. None of the chemical evolution models currently available in the literature satisfactorily represents the global chemical enrichment processes of SMC clusters., Comment: 49 pages, 15 figures. Accepted for publication in AJ

We obtained spectra of red giants in 15 Small Magellanic Cloud (SMC) clusters in the region of the CaII lines with FORS2 on the Very Large Telescope (VLT). We determined the mean metallicity and radial velocity with mean errors of 0.05 dex and 2.6 km/s, respectively, from a mean of 6.5 members per cluster. One cluster (B113) was too young for a reliable metallicity determination and was excluded from the sample. We combined the sample studied here with 15 clusters previously studied by us using the same technique, and with 7 clusters whose metallicities determined by other authors are on a scale similar to ours. This compilation of 36 clusters is the largest SMC cluster sample currently available with accurate and homogeneously determined metallicities. We found a high probability that the metallicity distribution is bimodal, with potential peaks at -1.1 and -0.8 dex. Our data show no strong evidence of a metallicity gradient in the SMC clusters, somewhat at odds with recent evidence from CaT spectra of a large sample of field stars Dobbie et al. (2014). This may be revealing possible differences in the chemical history of clusters and field stars. Our clusters show a significant dispersion of metallicities, whatever age is considered, which could be reflecting the lack of a unique AMR in this galaxy. None of the chemical evolution models currently available in the literature satisfactorily represents the global chemical enrichment processes of SMC clusters., Comment: 49 pages, 15 figures. Accepted for publication in AJ

We present CMDs in the V and I bands for fifteen star clusters in the Small Magellanic Cloud (SMC) based on data taken with the Very Large Telescope (VLT, Chile). We selected these clusters from our previous work, wherein we derived cluster radial velocities and metallicities from Calcium II infrared triplet (CaT) spectra also taken with the VLT. We discovered that the ages of six of our clusters have been appreciably underestimated by previous studies, which used comparatively small telescopes, graphically illustrating the need for large apertures to obtain reliable ages of old and intermediate-age SMC star clusters. In particular, three of these clusters, L4, L6 and L110, turn out to be amongst the oldest SMC clusters known, with ages of 7.9 +- 1.1, 8.7 +- 1.2 and 7.6 +- 1.0 Gyr, respectively, helping to fill a possible "SMC cluster age gap" (Glatt et al. 2008). Using the present ages and metallicities from Parisi et al. (2009), we analyze the age distribution, age gradient and age metallicity relation (AMR) of a sample of SMC clusters measured homogeneously. There is a suggestion of bimodality in the age distribution but it does not show a constant slope for the first 4 Gyr (Piatti 2011), and we find no evidence for an age gradient. Due to the improved ages of our cluster sample, we find that our AMR is now better represented in the intermediate/old period than that we derived in Parisi et al. (2009), where we simply took ages available in the literature. Additionally, clusters younger than aprox. 4 Gyr now show better agreement with the bursting model, but we confirm that this model is not a good representation of the AMR during the intermediate-age/old period. A more complicated model is needed to explain the SMC chemical evolution in that period., Comment: 76 pages, 32 figures. Accepted for publication in AJ

We present CMDs in the V and I bands for fifteen star clusters in the Small Magellanic Cloud (SMC) based on data taken with the Very Large Telescope (VLT, Chile). We selected these clusters from our previous work, wherein we derived cluster radial velocities and metallicities from Calcium II infrared triplet (CaT) spectra also taken with the VLT. We discovered that the ages of six of our clusters have been appreciably underestimated by previous studies, which used comparatively small telescopes, graphically illustrating the need for large apertures to obtain reliable ages of old and intermediate-age SMC star clusters. In particular, three of these clusters, L4, L6 and L110, turn out to be amongst the oldest SMC clusters known, with ages of 7.9 +- 1.1, 8.7 +- 1.2 and 7.6 +- 1.0 Gyr, respectively, helping to fill a possible "SMC cluster age gap" (Glatt et al. 2008). Using the present ages and metallicities from Parisi et al. (2009), we analyze the age distribution, age gradient and age metallicity relation (AMR) of a sample of SMC clusters measured homogeneously. There is a suggestion of bimodality in the age distribution but it does not show a constant slope for the first 4 Gyr (Piatti 2011), and we find no evidence for an age gradient. Due to the improved ages of our cluster sample, we find that our AMR is now better represented in the intermediate/old period than that we derived in Parisi et al. (2009), where we simply took ages available in the literature. Additionally, clusters younger than aprox. 4 Gyr now show better agreement with the bursting model, but we confirm that this model is not a good representation of the AMR during the intermediate-age/old period. A more complicated model is needed to explain the SMC chemical evolution in that period., Comment: 76 pages, 32 figures. Accepted for publication in AJ

We present integrated spectra in the optical range () for 27 concentrated star clusters (SCs) of the Large Magellanic Cloud (LMC). colour excesses and ages of these SCs are determined from two different methods: (1) Measurement of equivalent widths in selected spectral windows. (2) Comparison of the integrated spectra with template spectra. The current sample of integrated spectra complements previous ones in an effort to gather a spectral library with several clusters per age bin. FULL TEXT IN SPANISH

We present flux-calibrated integrated spectra in the optical range obtained with the REOSC spectrograph (CASLEO, Argentina) for 9 concentrated stellar clusters belonging to the Large Magellanic Cloud, one of which was not previously studied. We estimate simultaneously age and foreground reddening by using the algorithm FISA. For the studied sample, we derive ages between 2 Myr and 350 Myr and foreground reddening E(B-V) values in the range 0.00--0.23 mag. These values are mostly in agreement with the ones found by other authors. FULL TEXT IN SPANISH

We present integrated spectra in the optical range for 10 concentrated Mag- ellanic Clouds' (MCs) stellar clusters, six of them belonging to the Large Magellanic Cloud, and the other four to the Small Magellanic Cloud. The spectra were obtained with the EFOSC2 spectrograph (NTT-ESO, La Silla, Chile). We estimate simultaneously age and foreground reddening by com- paring the continuum distribution and line strengths of the cluster spectra with those of template spectra. The present cluster sample complements previous ones, in an effort to create a spectral library for the MCs with sev- eral clusters per age bin. FULL TEXT IN SPANISH

Following specific criteria, we have carefully selected objects catalogued as galactic open cluster candidates. Out of a total of 58 small angular diameter selected objects without previous studies, we obtained integrated spectra of 18 of them at CASLEO (San Juan, Argentina). Using a computational tool specially developed for the analysis of integrated spectra, reddenings and ages of the observed clusters were determined for the first time. FULL TEXT IN SPANISH

We describe the public ESO near-IR variability survey (VVV) scanning the Milky Way bulge and an adjacent section of the mid-plane where star formation activity is high. The survey will take 1929 hours of observations with the 4-metre VISTA telescope during five years (2010-2014), covering ~10^9 point sources across an area of 520 deg^2, including 33 known globular clusters and ~350 open clusters. The final product will be a deep near-IR atlas in five passbands (0.9-2.5 microns) and a catalogue of more than 10^6 variable point sources. Unlike single-epoch surveys that, in most cases, only produce 2-D maps, the VVV variable star survey will enable the construction of a 3-D map of the surveyed region using well-understood distance indicators such as RR Lyrae stars, and Cepheids. It will yield important information on the ages of the populations. The observations will be combined with data from MACHO, OGLE, EROS, VST, Spitzer, HST, Chandra, INTEGRAL, WISE, Fermi LAT, XMM-Newton, GAIA and ALMA for a complete understanding of the variable sources in the inner Milky Way. This public survey will provide data available to the whole community and therefore will enable further studies of the history of the Milky Way, its globular cluster evolution, and the population census of the Galactic Bulge and center, as well as the investigations of the star forming regions in the disk. The combined variable star catalogues will have important implications for theoretical investigations of pulsation properties of stars., Comment: accepted for publication in New Astronomy

We describe the public ESO near-IR variability survey (VVV) scanning the Milky Way bulge and an adjacent section of the mid-plane where star formation activity is high. The survey will take 1929 hours of observations with the 4-metre VISTA telescope during five years (2010-2014), covering ~10^9 point sources across an area of 520 deg^2, including 33 known globular clusters and ~350 open clusters. The final product will be a deep near-IR atlas in five passbands (0.9-2.5 microns) and a catalogue of more than 10^6 variable point sources. Unlike single-epoch surveys that, in most cases, only produce 2-D maps, the VVV variable star survey will enable the construction of a 3-D map of the surveyed region using well-understood distance indicators such as RR Lyrae stars, and Cepheids. It will yield important information on the ages of the populations. The observations will be combined with data from MACHO, OGLE, EROS, VST, Spitzer, HST, Chandra, INTEGRAL, WISE, Fermi LAT, XMM-Newton, GAIA and ALMA for a complete understanding of the variable sources in the inner Milky Way. This public survey will provide data available to the whole community and therefore will enable further studies of the history of the Milky Way, its globular cluster evolution, and the population census of the Galactic Bulge and center, as well as the investigations of the star forming regions in the disk. The combined variable star catalogues will have important implications for theoretical investigations of pulsation properties of stars., Comment: accepted for publication in New Astronomy

We propose a public IR variability survey, named \Vista Variables in the Vía Láctea" (V V V ), of the Milky Way bulge and an adjacent section of the mid-plane where star formation activity is high. This would take 1920 hours, covering ~ 109 point sources within an area of 520 sq deg, including 33 known globular clusters and ~ 350 open clusters. The final products will be a deep IR atlas in 5 passbands and a catalogue of ~ 106 variable point sources. These will produce a 3-D map of the surveyed region (unlike single-epoch surveys that only give 2-D maps) using well-understood primary distance indicators such as RR Lyrae stars. It will yield important information on the ages of the populations. The observations will be combined with data from MACHO, OGLE, EROS, VST, SPITZER, HST, CHANDRA, INTEGRAL, and ALMA for a complete understanding of the variable sources in the inner Milky Way. Several important implications for the history of the Milky Way, for globular cluster evolution, for the population census of the bulge and center, and for pulsation theory would follow from this survey.

We propose a public IR variability survey, named \Vista Variables in the Vía Láctea" (V V V ), of the Milky Way bulge and an adjacent section of the mid-plane where star formation activity is high. This would take 1920 hours, covering ~ 109 point sources within an area of 520 sq deg, including 33 known globular clusters and ~ 350 open clusters. The final products will be a deep IR atlas in 5 passbands and a catalogue of ~ 106 variable point sources. These will produce a 3-D map of the surveyed region (unlike single-epoch surveys that only give 2-D maps) using well-understood primary distance indicators such as RR Lyrae stars. It will yield important information on the ages of the populations. The observations will be combined with data from MACHO, OGLE, EROS, VST, SPITZER, HST, CHANDRA, INTEGRAL, and ALMA for a complete understanding of the variable sources in the inner Milky Way. Several important implications for the history of the Milky Way, for globular cluster evolution, for the population census of the bulge and center, and for pulsation theory would follow from this survey.

37 potential members of the red-giant branches of NGC 6192, NGC 6208 and NGC 6268 were observed in the UBV system, while 22 of them were also observed in the DDO system. The observations were made at La Silla and Cerro Tololo Inter-American observatories (Chile), using pulse-counting photoelectric photometers. Coravel radial velocities (RVs) were obtained at La Silla for 24 red giant candidates in the three clusters. Five stars of NGC 6192 have RVs in the narrow range -8.8 km/s < VR < -6.4 km/s, including two new spectroscopic binaries (SBs). Three stars of NGC 6208 - including a new SB - and three stars of NGC 6268 show similar RVs so that their physical membership to NGC 6208 and NGC 6268, respectively, is highly probable. Mean radial velocities are: -7.7 ± 0.38 km/s (NGC 6192), -32.21 ± 0.28 km/s (NGC 6208) and -15.11 ± 0.08 km/s (NGC 6268). We have also derived the following mean E(B-V) values from Janes (1977) iterative method: 0.63 ± 0.02 (NGC 6192), 0.31 ± 0.02 (NGC 6208) and 0.43 ± 0.02 (NGC 6268)