0000000000303633

AUTHOR

B. Lopez-marti

showing 3 related works from this author

Does the galaxy correlation length increase with the sample depth?

2001

We have analyzed the behavior of the correlation length, $r_0$, as a function of the sample depth by extracting from the CfA2 redshift survey volume--limited samples out to increasing distances. For a fractal distribution, the value of $r_0$ would increase with the volume occupied by the sample. We find no linear increase for the CfA2 samples of the sort that would be expected if the Universe preserved its small scale fractal character out to the distances considered (60--100$\hmpc$). The results instead show a roughly constant value for $r_0$ as a function of the size of the sample, with small fluctuations due to local inhomogeneities and luminosity segregation. Thus the fractal picture ca…

PhysicsSample (material)Astrophysics (astro-ph)FOS: Physical sciencesAstronomy and AstrophysicsAstrophysicsFunction (mathematics)Astrophysics::Cosmology and Extragalactic AstrophysicsAstrophysicsRedshift surveyGalaxyLuminosityFractalDistribution (mathematics)Space and Planetary ScienceConstant (mathematics)
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Correlations at large scale

2002

We show point processes generated in different ways and having different structure, presenting very similar power-law two--point correlation functions at small scales and quite different shapes at large scales.

Astrophysics (astro-ph)FOS: Physical sciencesAstrophysics
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Brown Dwarfs in ChaI Dark Cloud

2004

We present the results of a multiband survey for brown dwarfs in the Chamaeleon I dark cloud with the Wide Field Imager (WFI) camera at the ESO/MPG 2.2-m telescope on La Silla (Chile) on 28-May to 03-Jun 1999. The survey has revealed a substantial population of brown dwarfs in this southern star-forming region. Candidates were selected from R, I and H{alpha} imaging observations. We also observed in two medium-band filters, M855 and M915, for spectral type determination. The former filter covers a wavelength range containing spectral features characteristic of M-dwarfs, while the latter lies in a relatively featureless wavelength region for these late-type objects. A correlation was found b…

interstellar mediumAstrophysics and AstronomyPhysicsAstrophysics::Cosmology and Extragalactic AstrophysicsPhotometryobservational astronomyPre main sequence starsStellar AstronomyMolecular cloudsAstrophysics::Solar and Stellar AstrophysicsAstrophysics::Earth and Planetary AstrophysicsPre-main sequence starsNatural SciencesAstrophysics::Galaxy AstrophysicsInfrared photometry
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