Browsing by Author "Vanzi, L."

Now showing 1 - 20 of 20
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    HD 76920 b pinned down: A detailed analysis of the most eccentric planetary system around an evolved star
    (2021) Bergmann, C.; Jones, M. I.; Zhao, J.; Mustill, A. J.; Brahm, R.; Torres, P.; Wittenmyer, R. A.; Gunn, F.; Pollard, K. R.; Zapata, A.; Vanzi, L.; Wang, Songhu
    We present 63 new multi-site radial velocity (RV) measurements of the K1III giant HD 76920, which was recently reported to host the most eccentric planet known to orbit an evolved star. We focused our observational efforts on the time around the predicted periastron passage and achieved near-continuous phase coverage of the corresponding RV peak. By combining our RV measurements from four different instruments with previously published ones, we confirm the highly eccentric nature of the system and find an even higher eccentricity of , an orbital period of 415.891(-0.039)(+0.043) d, and a minimum mass of 3.13(-0.43)(+0.41) M-J for the planet. The uncertainties in the orbital elements are greatly reduced, especially for the period and eccentricity. We also performed a detailed spectroscopic analysis to derive atmospheric stellar parameters, and thus the fundamental stellar parameters (M-*, R-*, L-*) taking into account the parallax from Gaia DR2, and independently determined the stellar mass and radius using asteroseismology. Intriguingly, at periastron, the planet comes to within 2.4 stellar radii of its host star's surface. However, we find that the planet is not currently experiencing any significant orbital decay and will not be engulfed by the stellar envelope for at least another 50-80 Myr. Finally, while we calculate a relatively high transit probability of 16%, we did not detect a transit in the TESS photometry.
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    Integral field near-infrared spectroscopy of II Zw 40
    (EDP SCIENCES S A, 2008) Vanzi, L.; Cresci, G.; Telles, E.; Melnick, J.
    We present integral field spectroscopy in the near-infrared of the nearby starburst galaxy II Zw 40. Our new observations provide an unprecedented detailed view of the interstellar medium and star formation of this galaxy. The radiation emitted by the galaxy is dominated by a giant HII region, which extends over an area of more than 400 pc in size. A few clusters are present in this area, however, one, in particular, appears to be the main source of ionizing photons. We derive the properties of this object and compare them with those of the 30 Doradus cluster in the Large magellanic cloud (LMC). We study the spatial distribution and velocity field of different components of the inetrstellar medium (ISM), mostly through the Bracket series lines, the molecular hydrogen spectrum, and [FeII]. We find that [FeII] and H-2 are mostly photon excited, but while the region emitting [FeII] is almost coincident with the giant HII region observed in the lines of atomic H and He, the H-2 has a quite different distribution in space and velocity. The age of the stellar population in the main cluster is such that no supernova (SN) should be present yet so that the gas kinematics must be dominated by the young stars. We do not see, in the starbursting region, any geometrical or dynamical structure that can be related to the large scale morphology of the galaxy.
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    Integral field spectroscopy in the near infrared of NGC 3125-A and SBS 0335-052
    (2011) Vanzi, L.; Cresci, G.; Sauvage, M.; Thompson, R.
    We present integral field spectroscopy in the near infrared of the nearby dwarf starburst galaxy NGC 3125-A and of the low metallicity dwarf galaxy SBS 0335-052. The use of adaptive optics in the observations produces sub-arcsecond angular resolution. We pinpoint the star forming cores of both galaxies, identify relevant ISM components such as dust, photo ionized gas, shock excited gas and molecular gas. We relate these components to the large scale star formation process of the galaxies. In particular we find the emission of the near infrared lines of H-2 and especially [FeII] does not coincide with the HII region in NGC 3125. We have the first clear detection of [FeII] in SBS 0335-052.
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    Integral-field near-infrared spectroscopy of two blue dwarf galaxies: NGC 5253 and He 2-10
    (EDP SCIENCES S A, 2010) Cresci, G.; Vanzi, L.; Sauvage, M.; Santangelo, G.; van der Werf, P.
    We present integral field spectroscopy in the near infrared (NIR) of He 2-10 and NGC 5253, two well known nearby dwarf irregular galaxies showing high star-formation rates. Our data provide an unprecedented detailed view of the interstellar medium and star formation in these galaxies, allowing us to obtain spatially resolved information from the NIR emission and absorption line tracers. We study the spatial distribution and kinematics of different components of the interstellar medium ( ISM) mostly through the Bracket series lines, the molecular hydrogen spectrum, [FeII] emission, and CO absorptions. Although the ISM is mostly photo-excited, as derived by the [FeII]/Br gamma and H(2) line ratios, some regions corresponding to non-thermal radio sources show a [FeII]/Br gamma excess due to a significant contribution of SN driven shocks. In He 2-10 we find that the molecular gas clouds, as traced by CO(2-1) and H(2) infrared line, show consistent morphologies and velocities when studied with the two different tracers. Moreover, there is a clear association with the youngest super star clusters as traced by the ionized gas. In the same galaxy we observe a cavity depleted of gas, which is surrounded by some of the most active regions of star formation, that we interpret as a signature of feedback-induced star formation from older episodes of star formation. Finally, we measured high turbulence in the ISM of both galaxies, sigma similar to 30-80 km s(-1), driven by the high star-formation activity.
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    Metallicity effects on dust properties in starbursting galaxies
    (2008) Engelbracht, C. W.; Rieke, G. H.; Gordon, K. D.; Smith, J. -D. T.; Werner, M. W.; Moustakas, J.; Willmer, C. N. A.; Vanzi, L.
    We present infrared observations of 66 starburst galaxies over the full range of oxygen abundances observed in local star-forming galaxies, from 12 + log(O/H) = 7.1 to 8.9. The data include imaging and spectroscopy from the Spitzer Space Telescope, supplemented by ground-based near-infrared imaging. We confirm a strong correlation of aromatic emission with metallicity, with a threshold at 12 + log(O/H) similar to 8. We show that the far-infrared color temperature of the large dust grains increases toward lower metallicity, peaking at a metallicity of 8 before turning over. We compute dust masses and compare them to H I masses from the literature to derive the ratio of atomic gas to dust, which increases by nearly 3 orders of magnitude between solar metallicity and a metallicity of 8, below which it flattens out. The abrupt change in aromatic emission at mid-infrared wavelengths thus appears to be reflected in the far-infrared properties, indicating that metallicity changes affect the composition of the full range of dust grain sizes that dominate the infrared emission. Although the great majority of galaxies show similar patterns of behavior as described above, there are three exceptions, SBS 0335-052E, Haro 11, and SHOC 391. Their infrared SEDs are dominated energetically by the mid-IR near 24 mu m rather than by the 60-200 mu m region. In addition, they have very weak near-infrared outputs and their SEDs are dominated by emission by dust at wavelengths as short as 1.8 mu m. The latter behavior indicates that the dominant star-forming episodes in them are extremely young. The component of the ISM responsible for the usual far-infrared emission appears to be either missing or inefficiently heated in these three galaxies.
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    MOONS: The New Multi-Object Spectrograph for the VLT
    (2020) Cirasuolo, M.; Fairley, A.; Rees, P.; González, O. A.; Taylor, W.; Maiolino, R.; Afonso, J.; Evans, C.; Flores, H.; Lilly, S.; Oliva, E.; Paltani, S.; Vanzi, L.; Abreu, M.; Accardo, M.; Adams, N.; Álvarez Méndez, D.; Amans, J. -P.; Amarantidis, S.; Atek, H.; Atkinson, D.; Banerji, M.; Barrett, J.; Barrientos, F.; Bauer, F.; Beard, S.; Béchet, C.; Belfiore, A.; Bellazzini, M.; Benoist, C.; Best, P.; Biazzo, K.; Black, M.; Boettger, D.; Bonifacio, P.; Bowler, R.; Bragaglia, A.; Brierley, S.; Brinchmann, J.; Brinkmann, M.; Buat, V.; Buitrago, F.; Burgarella, D.; Burningham, B.; Buscher, D.; Cabral, A.; Caffau, E.; Cardoso, L.; Carnall, A.; Carollo, M.; Castillo, R.; Castignani, G.; Catelan, Márcio; Cicone, C.; Cimatti, A.; Cioni, M. -R. L.; Clementini, G.; Cochrane, W.; Coelho, J.; Colling, M.; Contini, T.; Contreras, R.; Conzelmann, R.; Cresci, G.; Cropper, M.; Cucciati, O.; Cullen, F.; Cumani, C.; Curti, M.; Da Silva, A.; Daddi, E.; Dalessandro, E.; Dalessio, F.; Dauvin, L.; Davidson, G.; de Laverny, P.; Delplancke-Ströbele, F.; De Lucia, G.; Del Vecchio, C.; Dessauges-Zavadsky, M.; Di Matteo, P.; Dole, H.; Drass, H.; Dunlop, J.; Dünner, R.; Eales, S.; Ellis, R.; Enriques, B.; Fasola, G.; Ferguson, A.; Ferruzzi, D.; Fisher, M.; Flores, M.; Fontana, A.; Forchi, V.; Francois, P.; Franzetti, P.; Gargiulo, A.; Garilli, B.; Gaudemard, J.; Gieles, M.; Gilmore, G.; Ginolfi, M.; Gomes, J. M.; Guinouard, I.; Gutierrez, P.; Haigron, R.; Hammer, F.; Hammersley, P.; Haniff, C.; Harrison, C.; Haywood, M.; Hill, V.; Hubin, N.; Humphrey, A.; Ibata, R.; Infante, L.; Ives, D.; Ivison, R.; Iwert, O.; Jablonka, P.; Jakob, G.; Jarvis, M.; King, D.; Kneib, J. -P.; Laporte, P.; Lawrence, A.; Lee, D.; Li Causi, G.; Lorenzoni, S.; Lucatello, S.; Luco, Y.; Macleod, A.; Magliocchetti, M.; Magrini, L.; Mainieri, V.; Maire, C.; Mannucci, F.; Martin, N.; Matute, I.; Maurogordato, S.; McGee, S.; Mcleod, D.; McLure, R.; McMahon, R.; Melse, B. -T.; Messias, H.; Mucciarelli, A.; Nisini, B.; Nix, J.; Norberg, P.; Oesch, P.; Oliveira, A.; Origlia, L.; Padilla, N.; Palsa, R.; Pancino, E.; Papaderos, P.; Pappalardo, C.; Parry, I.; Pasquini, L.; Peacock, J.; Pedichini, F.; Pello, R.; Peng, Y.; Pentericci, L.; Pfuhl, O.; Piazzesi, R.; Popovic, D.; Pozzetti, L.; Puech, M.; Puzia, T.; Raichoor, A.; Randich, S.; Recio-Blanco, A.; Reis, S.; Reix, F.; Renzini, A.; Rodrigues, M.; Rojas, F.; Rojas-Arriagada, Á.; Rota, S.; Royer, F.; Sacco, G.; Sanchez-Janssen, R.; Sanna, N.; Santos, P.; Sarzi, M.; Schaerer, D.; Schiavon, R.; Schnell, R.; Schultheis, M.; Scodeggio, M.; Serjeant, S.; Shen, T. -C.; Simmonds, C.; Smoker, J.; Sobral, D.; Sordet, M.; Spérone, D.; Strachan, J.; Sun, X.; Swinbank, M.; Tait, G.; Tereno, I.; Tojeiro, R.; Torres, M.; Tosi, M.; Tozzi, A.; Tresiter, E.; Valenti, E.; Valenzuela Navarro, Á.; Vanzella, E.; Vergani, S.; Verhamme, A.; Vernet, J.; Vignali, C.; Vinther, J.; Von Dran, L.; Waring, C.; Watson, S.; Wild, V.; Willesme, B.; Woodward, B.; Wuyts, S.; Yang, Y.; Zamorani, G.; Zoccali, M.; Bluck, A.; Trussler, J.
    MOONS is the new Multi-Object Optical and Near-infrared Spectrograph currently under construction for the Very Large Telescope (VLT) at ESO. This remarkable instrument combines, for the first time, the collecting power of an 8-m telescope, 1000 fibres with individual robotic positioners, and both low- and high-resolution simultaneous spectral coverage across the 0.64-1.8 μm wavelength range. This facility will provide the astronomical community with a powerful, world-leading instrument able to serve a wide range of Galactic, extragalactic and cosmological studies. Construction is now proceeding full steam ahead and this overview article presents some of the science goals and the technical description of the MOONS instrument. More detailed information on the MOONS surveys is provided in the other dedicated articles in this Messenger issue....
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    Physical properties of Centaur (60558) 174P/Echeclus from stellar occultations
    (2024) Pereira, C. L.; Braga-Ribas, F.; Sicardy, B.; Gomes-Junior, A. R.; Ortiz, J. L.; Branco, H. C.; Camargo, J. I. B.; Morgado, B. E.; Vieira-Martins, R.; Assafin, M.; Benedetti-Rossi, G.; Desmars, J.; Emilio, M.; Morales, R.; Rommel, F. L.; Hayamizu, T.; Gondou, T.; Jehin, E.; Artola, R. A.; Asai, A.; Colazo, C.; Ducrot, E.; Duffard, R.; Fabrega, J.; Fernandez-Valenzuela, E.; Gillon, M.; Horaguchi, T.; Ida, M.; Kitazaki, K.; Mammana, L. A.; Maury, A.; Melita, M.; Morales, N.; Moya-Sierralta, C.; Owada, M.; Pollock, J.; Sanchez, J. L.; Santos-Sanz, P.; Sasanuma, N.; Sebastian, D.; Triaud, A.; Uchiyama, S.; Vanzi, L.; Watanabe, H.; Yamamura, H.
    The Centaur (60558) Echeclus was discovered on 2000 March 03, orbiting between the orbits of Jupiter and Uranus. After exhibiting frequent outbursts, it also received a comet designation, 174P. If the ejected material can be a source of debris to form additional structures, studying the surroundings of an active body like Echeclus can provide clues about the formation scenarios of rings, jets, or dusty shells around small bodies. Stellar occultation is a handy technique for this kind of investigation, as it can, from Earth-based observations, detect small structures with low opacity around these objects. Stellar occultation by Echeclus was predicted and observed in 2019, 2020, and 2021. We obtain upper detection limits of rings with widths larger than 0.5km and optical depth of tau = 0.02. These values are smaller than those of Chariklo's main ring; in other words, a Chariklo-like ring would have been detected. The occultation observed in 2020 provided two positive chords used to derive the triaxial dimensions of Echeclus based on a 3D model and pole orientation available in the literature. We obtained a = 37.0 +/- 0.6km, b = 28.4 +/- 0.5km, and c = 24.9 +/- 0.4km, resulting in an area-equivalent radius of 30.0 +/- 0.5km. Using the projected limb at the occultation epoch and the available absolute magnitude (), we calculate an albedo of p(v) = 0.050 +/- 0.003. Constraints on the object's density and internal friction are also proposed.
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    PLUTO's ATMOSPHERE FROM STELLAR OCCULTATIONS IN 2012 AND 2013
    (2015) Dias-Oliveira, A.; Sicardy, B.; Lellouch, E.; Vieira-Martins, R.; Assafin, M.; Camargo, J. I. B.; Braga-Ribas, F.; Gomes-Junior, A. R.; Benedetti-Rossi, G.; Colas, F.; Decock, A.; Doressoundiram, A.; Dumas, C.; Emilio, M.; Fabrega Polleri, J.; Gil-Hutton, R.; Gillon, M.; Girard, J. H.; Hau, G. K. T.; Ivanov, V. D.; Jehin, E.; Lecacheux, J.; Leiva, R.; Lopez-Sisterna, C.; Mancini, L.; Manfroid, J.; Maury, A.; Meza, E.; Morales, N.; Nagy, L.; Opitom, C.; Ortiz, J. L.; Pollock, J.; Roques, F.; Snodgrass, C.; Soulier, J. F.; Thirouin, A.; Vanzi, L.; Widemann, T.; Reichart, D. E.; LaCluyze, A. P.; Haislip, J. B.; Ivarsen, K. M.; Dominik, M.; Jorgensen, U.; Skottfelt, J.
    We analyze two multi-chord stellar occultations by Pluto that were observed on 2012 July 18th and 2013 May 4th, and respectively monitored from five and six sites. They provide a total of fifteen light curves, 12 of which were used for a simultaneous fit that uses a unique temperature profile, assuming a clear (no haze) and pure N-2 atmosphere, but allowing for a possible pressure variation between the two dates. We find a solution that satisfactorily fits (i.e., within the noise level) all of the 12 light curves, providing atmospheric constraints between similar to 1190 km (pressure similar to 11 mu bar) and similar to 1450 km (pressure similar to 0.1 mu bar) from Pluto's center. Our main results are: (1) the best-fitting temperature profile shows a stratosphere with a strong positive gradient between 1190 km (at 36 K, 11 mu bar) and r = 1215 km (6.0 mu bar), where a temperature maximum of 110 K is reached; above it is a mesosphere with a negative thermal gradient of -0.2 K km(-1) up to similar to 1390 km (0.25 mu bar), where the mesosphere connects itself to a more isothermal upper branch around 81 K; (2) the pressure shows a small (6%) but significant increase (6 sigma level) between the two dates; (3) without a troposphere, Pluto's radius is found to be R-P = 1190 +/- 5 km. Allowing for a troposphere, R-P is constrained to lie between 1168 and 1195 km; and (4) the currently measured CO abundance is too small to explain the mesospheric negative thermal gradient. Cooling by HCN is possible, but only if this species is largely saturated. Alternative explanations like zonal winds or vertical compositional variations of the atmosphere are unable to explain the observed mesospheric negative thermal gradient.
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    Resolving the molecular environment of super star clusters in Henize 2-10
    (EDP SCIENCES S A, 2009) Santangelo, G.; Testi, L.; Gregorini, L.; Leurini, S.; Vanzi, L.; Walmsley, C. M.; Wilner, D. J.
    Context. The rate of star formation both in the Galaxy and in external galaxies should be related to the physical properties of the molecular clouds from which stars form. This is expected for the starbursts found both in irregular galaxies and in some mergers. The dwarf galaxy Henize 2-10 is particularly interesting in this context as it shows a number of newly formed super star clusters (SSCs) associated with a very rich molecular environment.
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    Shaken, but not expelled: Gentle baryonic feedback from nearby starburst dwarf galaxies
    (2023) Marasco, A.; Belfiore, F.; Cresci, G.; Lelli, F.; Venturi, G.; Hunt, L. K.; Concas, A.; Marconi, A.; Mannucci, F.; Mingozzi, M.; McLeod, A. F.; Kumari, N.; Carniani, S.; Vanzi, L.; Ginolfi, M.
    Baryonic feedback is expected to play a key role in regulating the star formation of low-mass galaxies by producing galaxy-scale winds associated with mass-loading factors of beta similar to 1-50. We test this prediction using a sample of 19 nearby systems with stellar masses of 10(7) M-star/M-circle dot < 10(10), mostly lying above the main sequence of star-forming galaxies. We used MUSE at VLT optical integral field spectroscopy to study the warm ionised gas kinematics of these galaxies via a detailed modelling of their H alpha emission line. The ionised gas is characterised by irregular velocity fields, indicating the presence of non-circular motions of a few tens of km s(-1) within galaxy discs, but with intrinsic velocity dispersion of 40-60 km s(-1) that are only marginally larger than those measured in main-sequence galaxies. Galactic winds, defined as gas at velocities larger than the galaxy escape speed, encompass only a few percent of the observed fluxes. Mass outflow rates and loading factors are strongly dependent on M-star, the star formation rate (SFR), SFR surface density, and specific SFR (sSFR). For M-star of 10(8) M-circle dot we find beta similar or equal to 0.02, which is more than two orders of magnitude smaller than the values predicted by theoretical models of galaxy evolution. In our galaxy sample, baryonic feedback stimulates a gentle gas cycle rather than causing a large-scale blow-out.
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    Testing circumstellar disk lifetimes in young embedded clusters associated with the Vela Molecular Ridge
    (EDP SCIENCES S A, 2010) Massi, F.; Di Carlo, E.; Codella, C.; Testi, L.; Vanzi, L.; Gomes, J. I.
    Context. The Vela Molecular Ridge hosts a number of young embedded star clusters at the same evolutionary stage.
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    The molecular gas content of blue dwarf galaxies A collapsing detached molecular system in He 2-10?
    (EDP SCIENCES S A, 2009) Vanzi, L.; Combes, F.; Rubio, M.; Kunth, D.
    We present new observations of a sample of blue dwarf galaxies in the lines of CO(3-2) and HCN(4-3). The observations were obtained with the 12 m APEX telescope located at an altitude of 5100 m in Chajnantor (ALMA site). We detected CO(3-2) emission in seven of nine observed galaxies in our sample. In two galaxies, NGC 5253 and He 2-10, we mapped the central 20 '' x 20 '' in the CO(3-2) emission line. In He 2-10, we detected an extended component of molecular gas to the north-east of the main body of the galaxy. Comparing our data with previous HI and CO observations, we speculate that the presence of this detached cloud of molecular gas is produced by the merger already known in He 2-10, and could lead to the formation of a small tidal dwarf galaxy. The HCN(4-3) line was observed in NGC 5253 and He 2-10 only, but not detected.
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    The VVV Survey of the Milky Way: first year results
    (2011) Minniti, D.; Clariá, J. J.; Saito, R. K.; Hempel, M.; Lucas, P. W.; Rejkuba, M.; Toledo, I.; Gonzalez, O. A.; Alonso-García, J.; Irwin, M. J.; Gonzalez-Solares, E.; Cross, N.; Ivanov, V. D.; Soto, M.; Dékány, I.; Angeloni, R.; Catelan, Marcio; Amôres, E. B.; Gurovich, S.; Emerson, J. P.; Lewis, J.; Hodgkin, S.; Pietrukowicz, P.; Zoccali, M.; Sale, S. E.; Barbá, R.; Barbuy, B.; Beamin, J. C.; Helminiak, K.; Borissova, J.; Folkes, S. L.; Gamen, R. C.; Geisler, D.; Mauro, F.; Chené, A. -N.; Alonso, M. V.; Gunthardt, G.; Hanson, M.; Kerins, E.; Kurtev, R.; Majaess, D.; Martín, E.; Masetti, N.; Mirabel, I. F.; Monaco, L.; Moni Bidin, C.; Padilla, N.; Rojas, A.; Pietrzynski, G.; Saviane, I.; Valenti, E.; Weidmann, W.; López-Corredoira, M.; Ahumada, A. V.; Aigrain, S.; Arias, J. I.; Bica, E.; Bandyopadhyay, R. M.; Baume, G.; Bedin, L. R.; Bonatto, C.; Bronfman, L.; Carraro, G.; Contreras, C.; Davis, C. J.; de Grijs, R.; Dias, B.; Drew, J. E.; Fariña, C.; Feinstein, C.; Fernández Lajús, E.; Gieren, W.; Goldman, B.; Gosling, A.; Hambly, N. C.; Hoare, M.; Jordán, A.; Kinemuchi, K.; Maccarone, T.; Merlo, D. C.; Mennickent, R. E.; Morelli, L.; Motta, V.; Palma, T.; Popescu, B.; Parisi, M. C.; Parker, Q.; Pignata, G.; Read, M. A.; Ruiz, M. T.; Roman-Lopes, A.; Schreiber, M. R.; Schröder, A. C.; Smith, M.; Sodré, L., Jr.; Stephens, A. W.; Walton, N. A.; Zijlstra, A. A.; Tamura, M.; Tappert, C.; Thompson, M. A.; Vanzi, L.
    The VISTA Variables in the Via Lactea (VVV) is an ESO public near-IR variability survey that is scanning the Milky Way bulge and an adjacent section of the Galactic mid-plane. The survey will take 1929 hours of observations with the VISTA 4.1-m telescope during five years, covering a billion point sources across an area of 520 sqdeg, including 36 known globular clusters and more than 350 open clusters. The final product will be a deep IR atlas in five passbands (0.9 - 2.5 microns) and a catalogue of more than a million variable point sources....
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    The VVV Survey: New Results (Part I)
    (2014) Minniti, D.; Saito, R. K.; Hempel, M.; Lucas, P. W.; Rejkuba, M.; Toledo, I.; Gonzalez, O. A.; Alonso-García, J.; Irwin, M. J.; Gonzalez-Solares, E.; Hodgkin, S. T.; Lewis, J. R.; Cross, N.; Ivanov, V. D.; Kerins, E.; Emerson, J. P.; Soto, M.; Amôres, E. B.; Gurovich, S.; Dékány, I.; Angeloni, R.; Beamin, J. C.; Catelan, Marcio; Padilla, N.; Zoccali, M.; Pietrukowicz, P.; Moni Bidin, C.; Mauro, F.; Geisler, D.; Folkes, S. L.; Sale, S. E.; Borissova, J.; Kurtev, R.; Ahumada, A. V.; Alonso, M. V.; Adamson, A.; Arias, J. I.; Bandyopadhyay, R. M.; Barbá, R. H.; Barbuy, B.; Baume, G. L.; Bedin, L. R.; Benjamin, R.; Bica, E.; Bonatto, C.; Bronfman, L.; Carraro, G.; Chenè, A. N.; Clariá, J. J.; Clarke, J. R. A.; Contreras, C.; Corvillón, A.; de Grijs, R.; Dias, B.; Drew, J. E.; Fariía, C.; Feinstein, C.; Fernández-Lajús, E.; Gamen, R. C.; Gieren, W.; Goldman, B.; González-Fernández, C.; Grand, R. J. J.; Gunthardt, G.; Hambly, N. C.; Hanson, M. M.; Helminiak, K.; Hoare, M. G.; Huckvale, L.; Jordán, A.; Kinemuchi, K.; Longmore, A.; López-Corredoira, M.; Maccarone, T.; Majaess, D.; Martín, E.; Masetti, N.; Mennickent, R. E.; Mirabel, I. F.; Monaco, L.; Morelli, L.; Motta, V.; Palma, T.; Parisi, M. C.; Parker, Q.; Peñaloza, F.; Pietrzyński, G.; Pignata, G.; Popescu, B.; Read, M. A.; Rojas, A.; Roman-Lopes, A.; Ruiz, M. T.; Saviane, I.; Schreiber, M. R.; Schröder, A. C.; Sharma, S.; Smith, M. D.; Sodré, L.; Stead, J.; Stephens, A. W.; Tamura, M.; Tappert, C.; Thompson, M. A.; Valenti, E.; Vanzi, L.; Walton, N. A.; Weidmann, W.; Zijlstra, A.
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    The VVV Survey: New Results (Part II)
    (2014) Minniti, D.; Saito, R. K.; Hempel, M.; Lucas, P. W.; Rejkuba, M.; Toledo, I.; Gonzalez, O. A.; Alonso-García, J.; Irwin, M. J.; Gonzalez-Solares, E.; Hodgkin, S. T.; Lewis, J. R.; Cross, N.; Ivanov, V. D.; Kerins, E.; Emerson, J. P.; Soto, M.; Amôres, E. B.; Gurovich, S.; Dékány, I.; Angeloni, R.; Beamin, J. C.; Catelan, Marcio; Padilla, N.; Zoccali, M.; Pietrukowicz, P.; Moni Bidin, C.; Mauro, F.; Geisler, D.; Folkes, S. L.; Sale, S. E.; Borissova, J.; Kurtev, R.; Ahumada, A. V.; Alonso, M. V.; Adamson, A.; Arias, J. I.; Bandyopadhyay, R. M.; Barbá, R. H.; Barbuy, B.; Baume, G. L.; Bedin, L. R.; Benjamin, R.; Bica, E.; Bonatto, C.; Bronfman, L.; Carraro, G.; Chenè, A. N.; Clariá, J. J.; Clarke, J. R. A.; Contreras, C.; Corvillón, A.; de Grijs, R.; Dias, B.; Drew, J. E.; Fariña, C.; Feinstein, C.; Fernández-Lajús, E.; Gamen, R. C.; Gieren, W.; Goldman, B.; González-Fernández, C.; Grand, R. J. J.; Gunthardt, G.; Hambly, N. C.; Hanson, M. M.; Helminiak, K.; Hoare, M. G.; Huckvale, L.; Jordán, A.; Kinemuchi, K.; Longmore, A.; López-Corredoira, M.; Maccarone, T.; Majaess, D.; Martín, E.; Masetti, N.; Mennickent, R. E.; Mirabel, I. F.; Monaco, L.; Morelli, L.; Motta, V.; Palma, T.; Parisi, M. C.; Parker, Q.; Peñaloza, F.; Pietrzyński, G.; Pignata, G.; Popescu, B.; Read, M. A.; Rojas, A.; Roman-Lopes, A.; Ruiz, M. T.; Saviane, I.; Schreiber, M. R.; Schröder, A. C.; Sharma, S.; Smith, M. D.; Sodré, L.; Stead, J.; Stephens, A. W.; Tamura, M.; Tappert, C.; Thompson, M. A.; Valenti, E.; Vanzi, L.; Walton, N. A.; Weidmann, W.; Zijlstra, A.
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    Thermal structure and composition of Jupiter's Great Red Spot from high-resolution thermal imaging
    (ACADEMIC PRESS INC ELSEVIER SCIENCE, 2010) Fletcher, Leigh N.; Orton, G. S.; Mousis, O.; Yanamandra Fisher, P.; Parrish, P. D.; Irwin, P. G. J.; Fisher, B. M.; Vanzi, L.; Fujiyoshi, T.; Fuse, T.; Simon Miller, A. A.; Edkins, E.; Hayward, T. L.; De Buizer, J.
    Thermal-IR imaging from space-borne and ground-based observatories was used to investigate the temperature. composition and aerosol structure of Jupiter's Great Red Spot (GRS) and its temporal variability between 1995 and 2008. An elliptical warm core, extending over 8 degrees of longitude and 3 degrees of latitude, was observed within the cold anticyclonic vortex at 21 degrees S. The warm airmass is co-located with the deepest red coloration of the GRS interior. The maximum contrast between the core and the coldest regions of the GRS was 3.0-3.5 K in the north-south direction at 400 mbar atmospheric pressure, although the warmer temperatures are present throughout the 150-500 mbar range. The resulting thermal gradients cause counter-rotating flow in the GRS center to decay with altitude into the lower stratosphere. The elliptical warm airmass was too small to be observed in IRTF imaging prior to 2006, but was present throughout the 2006-2008 period in VLT, Subaru and Gemini imaging.
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    VISTA Milky Way Public Survey
    (2009) Minniti, D.; Lucas, P.; Ahumada, A. V.; Zoccali, M.; Catelan, Marcio; Morelli, L.; Tappert, C.; Pignata, G.; Toledo, I.; Ruiz, M. T.; Carraro, G.; Casassus, S.; Bronfman, L.; Barbá, R. H.; Gamen, R.; Gieren, W.; Geisler, D.; Pietrzynski, G.; Mennickent, R. E.; Kurtev, R.; Borissova, J.; Mirabel, F.; Ivanov, V. D.; Saviane, I.; Vanzi, L.; Monaco, L.; Rejkuba, M.; Messineo, M.; Bedin, L.; Stephens, A.; Barbuy, B.; Bica, E.; Clariá, J. J.; CASU (VDFS) Team; WFAU (VDFS) Team; Emerson, J.; Drew, J.; López-Correidora, M.; Martin, E.; Goldman, B.; Gianinni, T.; Eisloeffel, J.; Groot, P.; Fabregat, J.; Hambly, N.; Longmore, A.; Walton, N.; de Grijs, R.; Hoare, M.; Schroeder, A.; Naylor, T.; Barlow, M.; Zijlstra, A.; White, G.; Gosling, A.; McGowan, K.; Adamson, A.; Bandyopadhyay, R.; Thompson, M.; Cropper, M.; Lucey, J.; Kerins, E.; Hodgkin, S.; Pinfield, D.
    We propose a public IR variability survey, named ``Vista Variables in the Vía Láctea'' (VVV), 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 ∼ 10^9 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 ∼ 10^6 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....
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    VISTA Variables in the Via Lactea (VVV): Current Status and First Results
    (2010) Saito, R.; Hempel, M.; Alonso-García, J.; Toledo, I.; Borissova, J.; González, O.; Beamin, J. C.; Minniti, D.; Lucas, P.; Emerson, J.; Ahumada, A.; Aigrain, S.; Alonso, M. V.; Amôres, E.; Angeloni, R.; Arias, J.; Bandyopadhyay, R.; Barbá, R.; Barbuy, B.; Baume, G.; Bedin, L.; Bica, E.; Bronfman, L.; Carraro, G.; Catelan, Marcio; Clariá, J.; Contreras, C.; Cross, N.; Davis, C.; de Grijs, R.; Dékány, I.; Janet Drew, J. D.; Fariña, C.; Feinstein, C.; Fernández Lajús, E.; Folkes, S.; Gamen, R.; Geisler, D.; Gieren, W.; Goldman, B.; Gosling, A.; Gunthardt, G.; Gurovich, S.; Hambly, N.; Hanson, M.; Hoare, M.; Irwin, M.; Ivanov, V.; Jordán, A.; Kerins, E.; Kinemuchi, K.; Kurtev, R.; Longmore, A.; López-Corredoira, M.; Maccarone, T.; Martín, E.; Masetti, N.; Mennickent, R.; Merlo, D.; Messineo, M.; Mirabel, F.; Monaco, L.; Moni Bidin, C.; Morelli, L.; Padilla, N.; Palma, T.; Parisi, M. C.; Parker, Q.; Pavani, D.; Pietrukowicz, P.; Pietrzynski, G.; Pignata, G.; Rejkuba, M.; Rojas, A.; Roman Lopes, A.; Ruiz, M. T.; Sale, S.; Saviane, I.; Schreiber, M.; Schröder, A.; Sharma, S.; Smith, M.; Sodré, L., Jr.; Soto, M.; Stephens, A.; Tamura, M.; Tappert, C.; Thompson, M.; Valenti, E.; Vanzi, L.; Weidmann, W.; Zoccali, M.
    VISTA Variables in the Vía Láctea (VVV) is a public ESO near-IR variability survey aimed at scanning the Milky Way Bulge and an adjacent section of the mid-plane. VVV observations started in October 2009 during ESO science verification. Regular observations for the first year of the survey have been conducted since February 2010 and will cover a total area of 520 square degrees in five passbands and five epochs. Here we address the first results obtained from the VVV Survey as well as the current status of the observations....
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    VISTA Variables in the Vía Láctea (VVV): Halfway Status and Results
    (2014) Hempel, M.; Minniti, D.; Dékány, I.; Saito, R. K.; Lucas, P. W.; Emerson, J. P.; Ahumada, A. V.; Aigrain, S.; Alonso, M. V.; Alonso-García, J.; Amôres, E. B.; Angeloni, R.; Arias, J.; Bandyopadhyay, R.; Barbá, R. H.; Barbuy, B.; Baume, G.; Beamin, J. C.; Bedin, L.; Bica, E.; Borissova, J.; Bronfman, L.; Carraro, G.; Catelan, Marcio; Clariá, J. J.; Contreras, C.; Cross, N.; Davis, C.; de Grijs, R.; Drew, J. E.; Fariña, C.; Feinstein, C.; Fernández-Lajús, E. F.; Folkes, S.; Gamen, R. C.; Geisler, D.; Gieren, W.; Goldman, B.; González, O.; Gosling, A.; Gunthardt, G.; Gurovich, S.; Hambly, N. C.; Hanson, M.; Hoare, M.; Irwin, M. J.; Ivanov, V. D.; Jordán, A.; Kerins, E.; Kinemuchi, K.; Kurtev, R.; Longmore, A.; López-Corredoira, M.; Maccarone, T.; Martín, E.; Masetti, N.; Mennickent, R. E.; Merlo, D.; Messineo, M.; Mirabel, I. F.; Monaco, L.; Moni-Bidin, C.; Morelli, L.; Padilla, N.; Palma, T.; Parisi, M. C.; Parker, Q.; Pavani, D.; Pietrukowicz, P.; Pietrzynski, G.; Pignata, G.; Rejkuba, M.; Rojas, A.; Roman-Lopes, A.; Ruiz, M. T.; Sale, S. E.; Saviane, I.; Schreiber, M. R.; Schröder, A. C.; Sharma, S.; Smith, M.; Sodré, L., Jr.; Soto, M.; Stephens, A. W.; Tamura, M.; Tappert, C.; Thompson, M. A.; Toledo, I.; Valenti, E.; Vanzi, L.; Weidmann, W.; Zoccali, M.
    The VISTA Variables in the Vía Láctea (VVV) survey is one of six near-infrared ESO public surveys, and is now in its fourth year of observing. Although far from being complete, the VVV survey has already delivered many results, some directly connected to the intended science goals (detection of variable stars, microlensing events, new star clusters), others concerning more exotic objects, e.g., novae. Now, at the end of the fourth observing period, and comprising roughly 50% of the proposed observations, the status of the survey, as well some of results based on the VVV data, are presented....
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    VVV DR1: The first data release of the Milky Way bulge and southern plane from the near-infrared ESO public survey VISTA variables in the Via Lactea
    (EDP SCIENCES S A, 2012) Saito, R. K.; Hempel, M.; Minniti, D.; Lucas, P. W.; Rejkuba, M.; Toledo, I.; Gonzalez, O. A.; Alonso Garcia, J.; Irwin, M. J.; Gonzalez Solares, E.; Hodgkin, S. T.; Lewis, J. R.; Cross, N.; Ivanov, V. D.; Kerins, E.; Emerson, J. P.; Soto, M.; Amores, E. B.; Gurovich, S.; Dekany, I.; Angeloni, R.; Beamin, J. C.; Catelan, M.; Padilla, N.; Zoccali, M.; Pietrukowicz, P.; Bidin, C. Moni; Mauro, F.; Geisler, D.; Folkes, S. L.; Sale, S. E.; Borissova, J.; Kurtev, R.; Ahumada, A. V.; Alonso, M. V.; Adamson, A.; Arias, J. I.; Bandyopadhyay, R. M.; Barba, R. H.; Barbuy, B.; Baume, G. L.; Bedin, L. R.; Bellini, A.; Benjamin, R.; Bica, E.; Bonatto, C.; Bronfman, L.; Carraro, G.; Chene, A. N.; Claria, J. J.; Clarke, J. R. A.; Contreras, C.; Corvillon, A.; de Grijs, R.; Dias, B.; Drew, J. E.; Farina, C.; Feinstein, C.; Fernandez Lajus, E.; Gamen, R. C.; Gieren, W.; Goldman, B.; Gonzalez Fernandez, C.; Grand, R. J. J.; Gunthardt, G.; Hambly, N. C.; Hanson, M. M.; Helminiak, K. G.; Hoare, M. G.; Huckvale, L.; Jordan, A.; Kinemuchi, K.; Longmore, A.; Lopez Corredoira, M.; Maccarone, T.; Majaess, D.; Martin, E. L.; Masetti, N.; Mennickent, R. E.; Mirabel, I. F.; Monaco, L.; Morelli, L.; Motta, V.; Palma, T.; Parisi, M. C.; Parker, Q.; Penaloza, F.; Pietrzynski, G.; Pignata, G.; Popescu, B.; Read, M. A.; Rojas, A.; Roman Lopes, A.; Ruiz, M. T.; Saviane, I.; Schreiber, M. R.; Schroeder, A. C.; Sharma, S.; Smith, M. D.; Sodre, L., Jr.; Stead, J.; Stephens, A. W.; Tamura, M.; Tappert, C.; Thompson, M. A.; Valenti, E.; Vanzi, L.; Walton, N. A.; Weidmann, W.; Zijlstra, A.
    Context. The ESO public survey VISTA variables in the Via Lactea (VVV) started in 2010. VVV targets 562 sq. deg in the Galactic bulge and an adjacent plane region and is expected to run for about five years.