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arXiv · 1909.05094

The VIMOS Public Extragalactic Redshift Survey (VIPERS) -- Environment-size relation of massive passive galaxies at 0.5 < z < 0.8

Abstract

We use the statistics of the VIPERS survey to investigate the relation between the surface mean stellar mass density Sigma=Mstar/(2*pi*Re^2) of massive passive galaxies (MPGs, Mstar>10^11 Msun) and their environment in the redshift range 0.5 2*10^11 Msun, we find an excess of MPGs with low Sigma and a deficit of high-Sigma MPGs in the densest regions wrt other environments. We interpret this result as due to the migration of some high-Sigma MPGs (<1% of the total population of MPGs) into low-Sigma MPGs, probably through mergers or cannibalism of small satellites. In summary, our results imply that the accretion of satellite galaxies has a marginal role in the mass-assembly history of most MPGs. We have previously found that the number density of VIPERS massive star-forming galaxies (MSFGs) declines rapidily from z=0.8 to z=0.5, which mirrors the rapid increase in the number density of MPGs. This indicates that the MSFGs at z>0.8 migrate to the MPG population. Here, we investigate the Sigma-delta relation of MSFGs at z>0.8 and find that it is consistent within 1 sigma with that of low-Sigma MPGs at z<0.8. Thus, the results of this and our previous paper show that MSFGs at z>0.8 are consistent in terms of number and environment with being the progenitors of low-Sigma MPGs at z<0.8.

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A. Gargiulo, O. Cucciati, B. Garilli, M. Scodeggio, M. Bolzonella, G. Zamorani, G. De Lucia, J. Krywult, L. Guzzo, B. R. Granett, S. de la Torre, U. Abbas, C. Adami, S. Arnouts, D. Bottini, A. Cappi, P. Franzetti, A. Fritz, C. Haines, A. J. Hawken, A. Iovino, V. Le Brun, O. Le Fèvre, D. Maccagni, K. Małek, F. Marulli, T. Moutard, M. Polletta, A. Pollo, L. A. M. Tasca, R. Tojeiro, D. Vergani, A. Zanichelli, J. Bel, E. Branchini, J. Coupon, O. Ilbert, L. Moscardini, J. A. Peacock. 2019-09-05. The VIMOS Public Extragalactic Redshift Survey (VIPERS) -- Environment-size relation of massive passive galaxies at 0.5 < z < 0.8. https://doi.org/10.1051/0004-6361/201833600

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