43,984 research outputs found
Study od a Slice at +9 to +15 degrees of Declination: I. The Neutral Hydrogen Content of Galaxies in Loose Groups
We examine the H1 content of spiral galaxies in groups by using a catalog of
loose groups of galaxies identified in a magnitude limited sample m < 15.7
spanning the range 8 h to 18 h in right ascension and +9 to +15 in declination.
The redshift completeness of the galaxy sample is ~95%. No significant effect
of H1 depletion is found, although there may be a hint that the earliest type
spirals are slightly deficient.Comment: 10 pages, Latex, 3 tables, 5 figures, to appear in the Astronomical
Journa
Contributions from Dilatonic Strings to the Flat Behaviour of the Rotational Curves in Galaxies
We analyse the flat behaviour of the rotational curves in some galaxies in
the framework of a dilatonic, current-carrying string. We determine the
expression of the tangential velocity of test objects following a stable
circular equatorial orbit in this spacetime.Comment: This version to be published in the Int. Journal of Modern Phys.
Redshift-Distance Survey of Early-Type Galaxies. IV. Dipoles of the Velocity Field
We use the recently completed redshift-distance survey of nearby early-type
galaxies (ENEAR) to measure the dipole component of the peculiar velocity field
to a depth of cz ~ 6000 km/s. The sample consists of 1145 galaxies brighter
than m_B=14.5 and cz < 7000 km/s, uniformly distributed over the whole sky, and
129 fainter cluster galaxies within the same volume. Most of the Dn-sigma
distances were obtained from new spectroscopic and photometric observations
conducted by this project, ensuring the homogeneity of the data over the whole
sky. These 1274 galaxies are objectively assigned to 696 objects -- 282
groups/clusters and 414 isolated galaxies. We find that within a volume of
radius ~ 6000 km/s, the best-fitting bulk flow has an amplitude of |vbulk| =220
+/- 42 km/s in the CMB restframe, pointing towards l=304 +/- 16 degrees, b=25
+/- 11 degrees. The error in the amplitude includes statistical, sampling and
possible systematic errors. This solution is in excellent agreement with that
obtained by the SFI Tully-Fisher survey. Our results suggest that most of the
motion of the Local Group is due to fluctuations within 6000 km/s, in contrast
to recent claims of large amplitude bulk motions on larger scales.Comment: 11 pages, 2 figures, ApJL, accepted (updated results; matches
accepted version
Ocorrência e controle de nematoses do cafeeiro em Rondônia.
Este trabalho, tem por objetivo realizar o levantamento da ocorrência destes fitopatógenos na cafeicultura rondoniense, para determinar os locais de maior ocorrência de nematóides (gêneros e espécies), visando a adoção de medidas de controle com maior eficiência.bitstream/item/42668/1/ct52-cafe.pd
Ocorrência das principais doenças causadas por fungos em cafeeiros de Rondônia e seu controle.
Neste trabalho foram enfocadas as doenças causadas por fungos, por serem consideradas mais importantes, em virtude desses patógenos infectarem diversos órgãos da planta, provocando várias alterações no desenvolvimento das suas funções fisiológicas e vitais.bitstream/item/42688/1/ct-51doencasdocafeeiro.pd
Qualidade sanitária de sementes de nó-de-cachorro (Heteropterys tomentosa).
bitstream/item/82283/1/CT104.pd
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