Examinando por Autor "Firpo, V."
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Ítem A colour-excess extinction map of the southern Galactic disc from the VVV and GLIMPSE surveys(Monthly Notices of the Royal Astronomical Society, 2019-09-11) Soto, M.; Barba, R.; Minniti, D.; Kunder, A.; Majaess, D.; Nilo-Castellon, J. L.; Alonso-García, J.; Leone, G.; Morelli, L.; Haikala, L.; Firpo, V.; Lucas, P.; Emerson, J. P.; Moni Bidin, C.; Geisler, D.; Saito, R. K.; Gurovich, S.; Contreras Ramos, R.; Rejkuba, M.; Barbieri, M.; Roman-Lopes, A.; Hempel, M.; Alonso, M. V.; Baravalle, L. D.; Borissova, J.; Kurtev, R.; Milla, F.An improved high-resolution and deep AKs foreground dust extinction map is presented for the Galactic disc area within 295◦ ≾ l ≾ 350◦, −1.0◦ ≾ b ≾ +1.0◦. At some longitudes the map reaches up to |b| ~ 2.25◦, for a total of ~148 deg2. The map was constructed via the Rayleigh–Jeans colour excess (RJCE) technique based on deep near-infrared (NIR) and mid-infrared (MIR) photometry. The new extinction map features a maximum bin size of 1 arcmin, and relies on NIR observations from the Two Micron All-Sky Survey (2MASS) and new data from ESO’s Vista Variables in the Vía Láctea (VVV) survey, in concert with MIR observations from the Galactic Legacy Infrared Mid-Plane Survey Extraordinaire. The VVV photometry penetrates ~4 mag fainter than 2MASS, and provides enhanced sampling of the underlying stellar populations in this heavily obscured region. Consequently, the new results supersede existing RJCE maps tied solely to brighter photometry, revealing a systematic underestimation of extinction in prior work that was based on shallower data. The new high-resolution and large-scale extinction map presented here is readily available to the community through a web query interface.Ítem An outflow in the Seyfert ESO 362-G18 revealed by Gemini-GMOS/IFU observations(EDP Sciences, 2018) Humire, P.K.; Nagar, N.M.; Finlez, C.; Firpo, V.; Slater, R.; Lena, D.; Soto-Pinto, P.; Muñoz-Vergara, D.; Riffel, R.A.; Schmitt, H.R.; Kraemer, S.B.; Schnorr-Müller, A.; Fischer, T.C.; Robinson, A.; Storchi-Bergmann, T.; Crenshaw, M.; Elvis, M.S.We present two-dimensional stellar and gaseous kinematics of the inner 0.7 × 1.2 kpc2 of the Seyfert 1.5 galaxy ESO 362-G18, derived from optical (4092-7338 Å) spectra obtained with the GMOS integral field spectrograph on the Gemini South telescope at a spatial resolution of ≈ 170 pc and spectral resolution of 36 km s-1. ESO 362-G18 is a strongly perturbed galaxy of morphological type Sa or S0/a, with a minor merger approaching along the NE direction. Previous studies have shown that the [O III] emission shows a fan-shaped extension of ≈ 10′′ to the SE. We detect the [O III] doublet, [N II] and Hα emission lines throughout our field of view. The stellar kinematics is dominated by circular motions in the galaxy plane, with a kinematic position angle of ≈ 137° and is centred approximately on the continuum peak. The gas kinematics is also dominated by rotation, with kinematic position angles ranging from 122° to 139°, projected velocity amplitudes of the order of 100 km s-1, and a mean velocity dispersion of 100 km s-1. A double-Gaussian fit to the [O III]λ5007 and Hα lines, which have the highest signal to noise ratios of the emission lines, reveal two kinematic components: (1) a component at lower radial velocities which we interpret as gas rotating in the galactic disk; and (2) a component with line of sight velocities 100-250 km s-1 higher than the systemic velocity, interpreted as originating in the outflowing gas within the AGN ionization cone. We estimate a mass outflow rate of 7.4 × 10-2 M⊙ yr-1 in the SE ionization cone (this rate doubles if we assume a biconical configuration), and a mass accretion rate on the supermassive black hole (SMBH) of 2.2 × 10-2 M⊙ yr-1. The total ionized gas mass within ∼84 pc of the nucleus is 3.3 × 105 M⊙; infall velocities of ∼34 km s-1 in this gas would be required to feed both the outflow and SMBH accretion. © ESO 2018.Ítem Hundreds of new cluster candidates in the VISTA Variables in the Vía Láctea survey DR1(Astronomy and Astrophysics, 2015-09) Barbá, R.H.; Roman-Lopes, A.; Nilo Castellón, J.L.; Firpo, V.; Minniti, D.; Lucas, P.; Emerson, J.P.; Hempel, M.; Soto, M.; Saito, R.K.Context. VISTA variables in the Vía Láctea is an ESO Public survey dedicated to scanning the bulge and an adjacent portion of the Galactic disk in the fourth quadrant using the VISTA telescope and its near-infrared camera VIRCAM. One of the leading goals of the VVV survey is to contribute to knowledge of the star cluster population of the Milky Way. Aims. To improve the census of Galactic star clusters, we performed a systematic and careful scan of the JHKs images of the Galactic plane section of the VVV survey. Methods. Our detection procedure is based on a combination of stellar density maps and visual inspection of promising features in the J-, H-, and KS-band images. The material examined are VVV JHKS color-composite images corresponding to Data Release 1 of VVV. Results. We report the discovery of 493 new infrared star cluster candidates. The analysis of the spatial distribution show that the clusters are very concentrated in the Galactic plane, presenting some local maxima around the position of large star-forming complexes, such as G305, RCW 95, and RCW 106. The vast majority of the new star cluster candidates are quite compact and generally surrounded by bright and/or dark nebulosities. IRAS point sources are associated with 59% of the sample, while 88% are associated with MSX point sources. GLIMPSE 8 μm images of the cluster candidates show a variety of morphologies, with 292 clusters dominated by knotty sources, while 361 clusters show some kind of nebulosity in this wavelength regime. Spatial cross-correlation with young stellar objects, masers, and extended green-object catalogs suggest that a large sample of the new cluster candidates are extremely young. In particular, 104 star clusters associated with methanol masers are excellent candidates for ongoing massive star formation. Also, there is a special set of sixteen cluster candidates that present clear signposts of star-forming activity having associated simultaneosly dark nebulae, young stellar objects, extended green objects, and masers. © ESO, 2015.