@Article{RibeiroCaTrCaLaLoSc:2013:ClGaGr,
               author = "Ribeiro, A. L. B. and Carvalho, Reinaldo Ramos de and Trevisan, 
                         Marina and Capelato, Hugo Vicente and La Barbera, F. and Lopes, P. 
                         A. A. and Schilling, A. C.",
          affiliation = "Laborat{\'o}rio de Astrof{\'{\i}}sica Te{\'o}rica e 
                         Observacional, Universidade Estadual de Santa Cruz-45650-000, 
                         Ilh{\'e}us-BA, Brazil and {Instituto Nacional de Pesquisas 
                         Espaciais (INPE)} and {Instituto Nacional de Pesquisas Espaciais 
                         (INPE)} and {Instituto Nacional de Pesquisas Espaciais (INPE)} and 
                         INAF-Osservatorio Astronomico di Capodimonte, Napoli, Italy and 
                         Observat{\'o}rio do Valongo, Universidade Federal do Rio de 
                         Janeiro, Brazil and Laborat{\'o}rio de Astrof{\'{\i}}sica 
                         Te{\'o}rica e Observacional, Universidade Estadual de Santa 
                         Cruz-45650-000, Ilh{\'e}us-BA, Brazil",
                title = "SPIDER IX - Classifying galaxy groups according to their velocity 
                         distribution",
              journal = "Monthly Notices of the Royal Astronomical Society",
                 year = "2013",
               volume = "434",
               number = "1",
                pages = "784--795",
             keywords = "galaxies, groups, general.",
             abstract = "We introduce a new method to study the velocity distribution of 
                         galaxy systems, the Hellinger Distance (HD), designed for 
                         detecting departures from a Gaussian velocity distribution. 
                         Testing different approaches to measure normality of a 
                         distribution, we conclude that HD is the least vulnerable method 
                         to type I and II statistical errors. We define a relaxed galactic 
                         system as the one with unimodal velocity distribution and a 
                         normality deviation below a critical value (HD < 0.05). In this 
                         work, we study the Gaussian nature of the velocity distribution of 
                         the Berlind group sample, and of the FoF groups from the 
                         Millennium simulation. For the Berlind group sample (z < 0.1), 67 
                         per cent of the systems are classified as relaxed, while for the 
                         Millennium sample we find 63 per cent (z = 0). We verify that in 
                         multi-modal groups the average mass of modes in high-multiplicity 
                         (N >= 20) systems are significantly larger than in 
                         low-multiplicity ones (N < 20), suggesting that groups experience 
                         a mass growth at an increasing virialization rate towards z = 0, 
                         with larger systems accreting more massive subunits. We also 
                         investigate the connection between galaxy properties ([Fe/H], Age, 
                         eClass, g-r, Rpetro and <mu_petro>) and the Gaussianity of the 
                         velocity distribution of the groups. Bright galaxies (Mr <=-20.7) 
                         residing in the inner and outer regions of groups do not show 
                         significant differences in the listed quantities regardless if the 
                         group has a Gaussian (G) or a Non-Gaussian (NG) velocity 
                         distribution. However, the situation is significantly different 
                         when we examine the faint galaxies (-20.7 <Mr <=-17.9). In G 
                         groups, there is a remarkable difference between the galaxy 
                         properties of the inner and outer galaxy populations, testifying 
                         how the environment is affecting the galaxies. Instead, in NG 
                         groups there is no segregation between the properties of galaxies 
                         in the inner and outer regions, showing that the properties of 
                         these galaxies still reflect the physical processes prevailing in 
                         the environment where they were found earlier.",
                  doi = "10.1093/mnras/stt1071",
                  url = "http://dx.doi.org/10.1093/mnras/stt1071",
                 issn = "0035-8711",
                label = "scopus 2013-11",
             language = "en",
           targetfile = "1306.4722v2.pdf",
        urlaccessdate = "27 abr. 2024"
}