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Identification and study of systems of galaxies in the Shapley supercluster
Based on the largest compilation of galaxies with redshift in the regionof the Shapley Supercluster (Proust et al. 2004, P2004), we identified122 galaxy systems, 60 of which are new systems. Using the SuperCOSMOScatalogue, we have assigned bj magnitudes to each galaxy inour compilation. The sample of galaxy systems was used to estimate themass function of systems in the range 1013 to 1015{Mȯ} h-1. We computed a lower value to thetotal mass in the region of the Shapley Supercluster with this massfunction. Using 15 mock catalogues we derived the mean mass that thesekinds of systems have before comparing it with that obtained from thereal data.
| FLASH redshift survey - I. Observations and catalogue
The FLAIR Shapley-Hydra (FLASH) redshift survey catalogue consists of4613 galaxies brighter than bJ= 16.7 (corrected for Galacticextinction) over a 700-deg2 region of sky in the generaldirection of the Local Group motion. The survey region is a70°× 10° strip spanning the sky from the ShapleySupercluster to the Hydra cluster, and contains 3141 galaxies withmeasured redshifts. Designed to explore the effect of the galaxyconcentrations in this direction (in particular the Supergalactic planeand the Shapley Supercluster) upon the Local Group motion, the 68 percent completeness allows us to sample the large-scale structure betterthan similar sparsely-sampled surveys. The survey region does notoverlap with the areas covered by ongoing wide-angle (Sloan or 2dF)complete redshift surveys. In this paper, the first in a series, wedescribe the observation and data reduction procedures, the analysis forthe redshift errors and survey completeness, and present the surveydata.
| Variability of Seyfert galaxies in the near-infrared - II. The unusual starburst Seyfert NGC7469
The bright Seyfert 1 and starburst galaxy NGC7469 has been monitored atJHKL for 13 yr. Its variations have been small, amounting to less than0.3 mag, except for an event in 1989 when the flux from its activenucleus declined to about one quarter of its normal level. Using thetechnique of flux variation gradients (FVGs), the variations have beenanalysed, taking into account the known JHK fluxes from the star-formingring surrounding the nucleus. By comparing the FVGs of NGC7469 withthose of other Seyfert galaxies, the nucleus of NGC 7469 is found tosuffer very little reddening. The active nucleus normally contributesmore than 50 per cent of the flux measured in the K and L bands throughan aperture of 12 arcsec diameter. Infrared excesses (above the fluxesexpected from stars) are observed from the circumnuclear ring at both Kand L and it is suggested that they arise from warm, small particlesthat also emit the aromatic hydrocarbon features seen in this galaxy.
| Variability of Seyfert galaxies in the near-infrared. I - an outburst in NGC 2992
The IR light curve of the Seyfert 1.9 galaxy NGC 2992 shows a strongoutburst between JD 244 7243 and 244 8734 of total energy 6 x 10 exp 43J and having an exponential decay. The colors of the variable componentsare extracted by the method of flux variation gradients and discussed interms of a hot dust model.
| Candidates for a southern extension of the Karachentsev catalogue of isolated pairs of galaxies.
Not Available
| Southern Galaxy Catalogue.
Not Available
| Atlas of interacting galaxies, Part. II and the concept of fragmentation of galaxies.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1977A&AS...28....1V&db_key=AST
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