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 h of observations with the 4-m VISTA telescope during 5 years (2010-2014), covering ˜109 point sources across an area of 520 deg2, 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 μm) and a catalogue of more than 106 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
Sixty‐five volatile compounds and 103 sensory attributes were evaluated in 32 virgin olive oil samples from three different Mediterranean countries. Volatile compounds were analyzed with a dynamic headspace gas‐chromatographic technique by using a thermal desorption cold‐trap injector. The sensory analysis was conducted by six panels composed of assessors from the United Kingdom, Spain, the Netherlands, Greece and Italy. Principal‐components analysis of sensory attributes was used to construct a statistical sensory wheel that represents the whole virgin olive oil flavor matrix. This wheel is composed of seven sectors that show the basic perceptions produced by the oil: green, bitter‐pungent, undesirable, ripe olives, ripe fruit, fruity and sweet. The boundaries of each sector were calculated from the circular standard deviation of its sensory attributes. The relationship between sensory and instrumental analysis was determined by projecting volatiles onto the sensory wheel. Correlations of each volatile with the first two components of the principal‐components analysis were taken as its coordinates (x, y) in the sensory wheel. Volatiles took up the most appropriate place within the sector that corresponded with their perception, and often close to the sensory attributes that explained their sensory properties. A gas‐chromatographic/sniffing method was applied to virgin olive oil samples to assess the aroma notes that corresponded to olive oil volatile compounds and to verify the relationships found by the sensory wheel procedure. Most (89%) of the volatiles were well classified. Use of the statistical sensory wheel as an appropriate method to relate volatile and sensory data was clearly demonstrated.
We study the kinematics and dynamics of the globular cluster system of NGC 1399, the brightest elliptical galaxy near the center of the Fornax cluster of galaxies. The observational data consists of medium-resolution spectra, obtained at the Very Large Telescope with FORS2 and the Mask Exchange Unit (MXU). Our sample comprises 468 radial velocities in the magnitude range 20 < m R < 23. This is the largest sample of globular cluster velocities around any galaxy obtained so far. Typical velocity uncertainties are 50 km s À1 , significantly improving on earlier samples. The radial range is 2 0 < r < 9 0 , corresponding to 11 kpc to 50 kpc of galactocentric distance. The shape of the velocity distribution of the sample is compatible with being a Gaussian distribution. However, under moderate error selection, a slight asymmetry is visible between high and low radial velocities. We find bright clusters with radial velocities below 800 km s À1 , while they are not found at the corresponding highvelocity side above 2000 km s À1 . There is the possibility that unbound clusters and/or objects in the foreground contaminate the NGC 1399 cluster sample. Under strong error selection, practically no objects are found with velocities lower than 800 km s À1 or higher than 2000 km s À1 . Since the extreme velocities influence the velocity dispersion considerably, uncertainty regarding the exact value of the dispersion remains. With the above velocity limits, we derive a projected velocity dispersion for the total sample of 274 AE 9 km s À1 which within the uncertainties remains constant over the entire radial range. Without any velocity restriction, it increases to 325 km s À1 . Guided by the bimodal color distribution of clusters, we distinguish between red clusters (CÀR > 1:6) and blue clusters (CÀR < 1:6), and find velocity dispersions for these groups of 255 AE 13 and 291 AE 14 km s À1 , respectively, again radially constant. Any possible rotation of either of these cluster populations is below the detection limit, with the exception of a weak signature of rotation for the blue clusters more distant than 6 0 . Spherical models point to a circular velocity of 419 AE 30 km s À1 , assuming isotropy for the red clusters. This value is constant out to 40 kpc. The inferred dark halo potential can be well represented by a logarithmic potential. A halo of the NFW type also provides a good fit to the observations. The orbital structure of the clusters can only be weakly constrained. It is consistent with isotropy for the red clusters and a slight tangential bias for the blue clusters. Some mass profiles derived from X-ray analyses do not agree with a constant circular velocity within our radial range, irrespective of its exact value. Interpreting the extreme low radial velocities as space velocities of bound clusters near their pericentric distances would require an extension of the cluster system of at least 200 kpc. Implications for formation scenarios of the cluster system are briefly commented on.
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