Artículos de revistas
Low X-ray luminosity galaxy clusters – II. Optical properties and morphological content at 0.18 < z < 0.70
Fecha
2014Registro en:
Monthly Notices of the Royal Astronomical Society, Oxford, v. 437, p. 2607-2620, 2014
0035-8711
10.1093/mnras/stt2072
Autor
Nilo Castellón, José Luis
Alonso, M. Victoria
García Lambas, Diego
O'Mill, Ana Laura
Valotto, Carlos
Carrasco, Eleazar R.
Cuevas, Héctor
Ramírez, Amelia
Institución
Resumen
This is the second of a series of papers on low X-ray luminosity galaxy clusters, in which
we present the r , g and i photometry obtained with Gemini Multi-Object Spectrograph
IMAGE at Gemini North and South telescopes for seven systems in the redshift range of 0.18
to 0.70. Optical magnitudes, colours and morphological parameters, namely, concentration
index, ellipticity and visual morphological classification, are also given. At lower redshifts,
the presence of a well-defined red cluster sequence extending by more than 4 mag showed that
these intermediate-mass clusters had reached a relaxed stage. This was confirmed by the small
fraction of blue galaxy members observed in the central regions of ∼0.75 Mpc. In contrast,
galaxy clusters at higher redshifts had a less important red cluster sequence. We also found
that the galaxy radial density profiles in these clusters were well fitted by a single power law.
At 0.18 < z < 0.70, we observed an increasing fraction of blue galaxies and a decreasing
fraction of lenticulars, with the early-type fraction remaining almost constant. Overall, the
results of these intermediate-mass clusters are in agreement with those for high-mass clusters