Grants related:
General
This project consists of two parts, each differentiated but both complementary: morphology and dynamics. Detailed study of the morphology of the Milky Way pretends to provide a data base for the stellar distribution in the most remote and heavily obscured regions of our Galaxy, through the development of semiempirical models based on the information in these catalogues. Kinematic and dynamical analysis, on the other hand, aims to aid our understanding of the origin of these observed features.
Our group has used a combination of its own data (which will include in the future spectroscopical observations with GRANTECAN/EMIR) and public-domain catalogues either in photometry (DENIS, 2MASS, UKIDSS, VISTA, SDSS) or spectroscopy (SDSS-APOGEE in near infrared, LAMOST). We have gathered detailed information on the stellar distribution of the dominant populations over a wide area of sky containing different structural components: the triaxial bulge, the long bar, the disc, the spiral arms, etc. The components of gas and dust are also a matter of study in infrared, or in microwave (analyses of Galactic contamination over the cosmic microwave background radiation, for instance with WMAP or PLANCK). Our research team has also become part of the Spanish node of Gaia with the idea of orientating part of our work towards the scientific exploitation of this mission, particularly with regard to the identification and study of large scale stellar populations in the Galaxy.
Members
Results
- Milky Way's disk much larger than previously thought. See press release of IAC: http://www.iac.es/divulgacion.php?op1=16&id=1385&lang=en
Scientific activity
Related publications
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Transformations between the 2MASS, SDSS, and BV I photometric systems for late-type giantsWe present colour transformations from Two Micron All Sky Survey (2MASS) photometric system to Johnson-Cousins system and to Sloan Digital Sky Survey (SDSS) system for late-type giants and vice versa. The giant star sample was formed using surface gravity constraints ({2 log g ≤ 3}) to Cayrel de Strobel et al.' s (2001) spectroscopic catalogueYaz, E. et al.
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82010 -
Transformations between 2MASS, SDSS and BVRI photometric systems: bridging the near-infrared and opticalWe present colour transformations for the conversion of the Two Micron All Sky Survey (2MASS) photometric system to the Johnson-Cousins UBVRI system and further into the Sloan Digital Sky Survey (SDSS) ugriz system. We have taken SDSS gri magnitudes of stars measured with the 2.5-m telescope from SDSS Data Release 5 (DR5), and BVRI and JHKsBilir, S. et al.
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32008 -
The long Galactic bar as seen by UKIDSS Galactic plane surveyContext: Over the past decade there have been a series of results supporting the hypothesis of the existence of a long thin bar in the Milky Way with a half-length of 4.5 kpc and a position angle of around 45°. This is apparently a very different structure from the triaxial bulge of the Galaxy, which is thicker and shorter and dominates the starCabrera-Lavers, A. et al.
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122008 -
The Distance, Mass, and Radius of the Neutron Star in 4U 1608-52Low-mass X-ray binaries (LMXBs) that show thermonuclear bursts are ideal sources for constraining the equation of state of neutron star matter. The lack of independent distance measurements for most of these sources, however, prevent a systematic exploration of the masses and radii of the neutron stars, hence limiting the equation-of-state studiesGüver, Tolga et al.
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42010 -
SDSS absolute magnitudes for thin-disc stars based on trigonometric parallaxesWe present a new luminosity-colour relation based on trigonometric parallaxes for thin-disc main-sequence stars in Sloan Digital Sky Survey (SDSS) photometry. We matched stars from the newly reduced Hipparcos catalogue with the ones taken from Two-Micron All-Sky Survey (2MASS) All-Sky Catalogue of Point Sources, and applied a series of constraintsBilir, S. et al.
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72009 -
Mergers and interactions in Sloan Digital Sky Survey type 2 quasars at z˜ 0.3-0.4. SDSS J143027.66-005614.8: a case studyWe present a compilation of Hubble Space Telescope (HST) images of 58 luminous Sloan Digital Sky Survey (SDSS) type 2 active galactic nuclei (AGNs) at ?. Of these, 42 are type 2 quasars, which is a good representation of all optically selected SDSS type 2 quasars in this z range. We find that the majority of the host galaxies are ellipticals (30/42Villar-Martín, M. et al.
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62012 -
Luminosity-colour relations for thin-disc main-sequence starsIn this study we present the absolute magnitude calibrations of thin-disc main-sequence stars in the optical , and in the near-infrared . Thin-disc stars are identified by means of Padova isochrones, and absolute magnitudes for the sample are evaluated via the newly reduced Hipparcos data. The obtained calibrations cover a large range of spectralBilir, S. et al.
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112008 -
Ground-based Multisite Observations of Two Transits of HD 80606bWe present ground-based optical observations of the 2009 September and 2010 January transits of HD 80606b. Based on three partial light curves of the 2009 September event, we derive a midtransit time of Tc [HJD] = 2455099.196 ± 0.026, which is about 1σ away from the previously predicted time. We observed the 2010 January event from nine differentShporer, A. et al.
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102010 -
Probing IGM large-scale flows: warps in galaxies at shells of voidsContext: Hydrodynamical cosmological simulations predict flows of the intergalactic medium along the radial vector of the voids, approximately in the direction of the infall of matter at the early stages of the galaxy formation. Aims: These flows might be detected by analysing the dependence of the warp amplitude on the inclination of the galaxiesLópez-Corredoira, M. et al.
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92008 -
Absence of significant cross-correlation between WMAP and SDSSAims: Several authors have claimed to detect a significant cross-correlation between microwave WMAP anisotropies and the SDSS galaxy distribution. We repeat these analyses to determine the different cross-correlation uncertainties caused by re-sampling errors and field-to-field fluctuations. The first type of error concerns overlapping sky regionsLópez-Corredoira, M. et al.
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42010 -
Detection of transit timing variations in excess of one hour in the Kepler multi-planet candidate system KOI 806 with the GTCAims: We report the detection of transit timing variations (TTVs) well in excess of one hour in the Kepler multi-planet candidate system KOI 806. This system exhibits transits consistent with three separate planets - a Super-Earth, a Jupiter, and a Saturn - lying very nearly in a 1:2:5 resonance, respectively. Methods: We used the Kepler publicTingley, B. et al.
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122011 -
Fossil groups origins. I. RX J105453.3+552102 a very massive and relaxed system at z ~ 0.5Context. The most accepted scenario for the origin of fossil groups is that they are galaxy associations in which the merging rate was fast and efficient. These systems have assembled half of their mass at early epoch of the Universe, subsequently growing by minor mergers, and therefore could contain a fossil record of the galaxy structureAguerri, J. A. L. et al.
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32011 -
Fossil group origins. II. Unveiling the formation of the brightest group galaxies through their scaling relationsContext. Fossil systems are galaxy associations dominated by a relatively isolated, bright elliptical galaxy, surrounded by a group of smaller galaxies lacking L∗ objects. Because of this extreme environment, fossil groups (FGs) are ideal laboratories for studying the mass assembly of brightest group galaxies (BGGs). Aims: We analyzed the nearMéndez-Abreu, J. et al.
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12012