The Mass Function of Field Galaxies at 0.4 < z < 1.2 Derived From the MUNICS K-Selected Sample

We derive the number density evolution of massive field galaxies in the redshift range 0.4 < z < 1.2 using the K-band selected field galaxy sample from the Munich Near-IR Cluster Survey (MUNICS). We rely on spectroscopically calibrated photometric redshifts to determine distances and absolute magnitudes in the rest-frame K-band. To assign mass-to-light ratios, we use two different approaches. First, we use an approach which maximizes the stellar mass for any K-band luminosity at any redshift. We take the mass-to-light ratio of a Simple Stellar Population (SSP) which is as old as the universe at the galaxy's redshift as a likely upper limit. Second, we assign each galaxy a mass-to-light ratio by fitting the galaxy's colours against a grid of composite stellar population models and taking their M/L. We compute the number density of galaxies more massive than 2 x 10^10 h^-2 Msun, 5 x 10^10 h^-2 Msun, and 1 x 10^11 h^-2 Msun, finding that the integrated stellar mass function is roughly constant for the lowest mass limit and that it decreases with redshift by a factor of ~ 3 and by a factor of ~ 6 for the two higher mass limits, respectively. This finding is in qualitative agreement with models of hierarchical galaxy formation, which predict that the number density of ~ M* objects is fairly constant while it decreases faster for more massive systems over the redshift range our data probe.Comment: 6 pages, 2 figures, to appear in the proceedings of the ESO/USM Workshop "The Mass of Galaxies at Low and High Redshift", Venice (Italy), October 24-26, 200

The Munich Near-Infrared Cluster Survey (MUNICS) - Number density evolution of massive field galaxies to z ~ 1.2 as derived from the K-band selected survey

We derive the number density evolution of massive field galaxies in the redshift range 0.4 < z < 1.2 using the K-band selected field galaxy sample from the Munich Near-IR Cluster Survey (MUNICS). We rely on spectroscopically calibrated photometric redshifts to determine distances and absolute magnitudes in the rest-frame K-band. To assign mass-to-light ratios, we use an approach which maximizes the stellar mass for any K-band luminosity at any redshift. We take the mass-to-light ratio, M/L_K, of a Simple Stellar Population (SSP) which is as old as the universe at the galaxy's redshift as a likely upper limit. This is the most extreme case of pure luminosity evolution and in a more realistic model M/L_K will probably decrease faster with redshift due to increased star formation. We compute the number density of galaxies more massive than 2 10^10 h^-2 solar masses, 5 10^10 h^-2 solar masses, and 1 10^11 h^-2 solar masses, finding that the integrated stellar mass function is roughly constant for the lowest mass limit and that it decreases with redshift by a factor of roughly 3 and by a factor of roughly 6 for the two higher mass limits, respectively. This finding is in qualitative agreement with models of hierarchical galaxy formation, which predict that the number density of ~ M* objects is fairly constant while it decreases faster for more massive systems over the redshift range our data probe.Comment: 4 pages, 5 figures, accepted for publication in ApJ Letter

Large-Scale Structure in the NIR-Selected MUNICS Survey

The Munich Near-IR Cluster Survey (MUNICS) is a wide-area, medium-deep, photometric survey selected in the K' band. The project's main scientific aims are the identification of galaxy clusters up to redshifts of unity and the selection of a large sample of field early-type galaxies up to z < 1.5 for evolutionary studies. We created a Large Scale Structure catalog, using a new structure finding technique specialized for photometric datasets, that we developed on the basis of a friends-of-friends algorithm. We tested the plausibility of the resulting galaxy group and cluster catalog with the help of Color-Magnitude Diagrams (CMD), as well as a likelihood- and Voronoi-approach.Comment: 4 pages, to appear in "The Evolution of Galaxies III. From Simple Approaches to Self-Consistent Models", proceedings of the 3rd EuroConference on the evolution of galaxies, held in Kiel, Germany, July 16-20, 200

Avaliação de frutos de tucumanzeiros selecionados para alto teor de óleo na polpa.

O tucumanzeiro Astrocaryum vulgare Mart. é uma palmeira arbórea da família Arecaceae, nativa da Amazônia, que possui caule em touceira e frutos com alto potencial econômico. Por ser uma espécie de múltipla utilidade, na última década passou a ser indicada como matéria prima para a produção de biodiesel. Análises quantitativas e qualitativas do óleo extraído da polpa dos frutos foram realizadas elevaram a seleção de matrizes com alto teor de óleo. Contudo informações sobre aspectos físicos de seus frutos ainda são inexistentes. Assim, este trabalho objetivou avaliar frutos de matrizes de tucumanzeiro selecionadas para alto teor de óleo na polpa. Foram coletadas 3 amostras de 5 frutos retirados de 3 cachos consecutivos de 29 matrizes selecionadas no BAG- tucumã da Amazônia Oriental. Os dados obtidos foram analisados por meio de estatística descritiva. Foi constatada variação para todos os caracteres analisados. Os frutos apresentaram em média 41,8 mm e 34,3 mm de diâmetro longitudinal e transversal, respectivamente. O peso médio dos frutos foi de 31,8g sendo que 19,9g constituiu a polpa, representando 62,58% de parte comestível. As espessuras da polpa, do endocarpo e da amêndoa foram 4,8 mm, 3,2 mm e 7,1 mm, respectivamente. Todas as matrizes apresentaram altos rendimentos de polpa por fruto variando de 54,8% a 69,7%. Portanto pode-se considerar que as matrizes selecionadas apresentam ampla variação e alto rendimento de polpa por fruto.VII ENAAG

The Contribution of the Smectic-Nematic Interface to the Surface Energy

The contribution of the smectic-nematic interface to the surface energy of a nematic liquid crystal sample is analyzed. By means of a simple model it is shown that the surface energy depends on the thickness of the region over which the transition smectic-nematic takes place. For perfectly flat substrates this thickness is of the order of the correlation length entering in the transition. An estimate of this contribution shows that it is greater than the one arising from the nematic-substrate interaction. Moreover, it is also shown that the surface energy determined in this way presents a non-monotonic behavior with the temperature.Comment: 10 pages, revte

Kinematics and morphology of ionized gas in Hickson Compact Group 18

We present new observations of $H\alpha$ emission in the Hickson Compact Group 18 (HCG 18) obtained with a scanning Fabry-Perot interferometer. The velocity field does not show motions of individual group members but, instead, a complex common velocity field for the whole group. The gas distribution is very asymmetric with clumps of maximum intensity coinciding with the optically brightest knots. Comparing $H\alpha$ and HI data we conclude that HCG 18 is not a compact group but instead a large irregular galaxy with several clumps of star formation.Comment: Accepted for publication in Astronomical Journal (13p 6 figures