Aims.We present a measurement of the dependence of galaxy clustering on galaxy stellar mass at redshift z˜0.9, based on the first-epoch data from the VVDS-Deep survey. Methods: Concentrating on the redshift interval 0.5<z<1.2, we measured the projected correlation function, w_p(r_p), within mass-selected sub-samples covering the range ~109 and ~1011~M_ȯ. We explored and quantify in detail the observational selection biases due to the flux-limited nature of the survey, both from the data themselves and with a suite of realistic mock samples constructed by coupling the Millennium Simulation to semi-analytic models. We identify the range of masses within which our main conclusions are robust against these effects. Serious incompleteness in mass is present below log (M/M_ȯ)=9.5, with about two thirds of the galaxies in the range 9109~M_ȯ to r_0=4.28-0.45+0.43~h-1 Mpc when only the most massive (M>1010.5~M_ȯ) are considered. At the same time, we observe a significant increase in the slope, which over the same range of masses, changes from γ=1.67-0.07+0.08 to γ=2.28-0.27+0.28. Comparison to the SDSS measurements at z˜0.15 shows that the evolution of w_p(r_p) is significant for samples of galaxies with M<1010.5~M_ȯ, while it is negligible for more massive objects. Considering the growth of structure, this implies that the linear bias bL of the most massive galaxies evolves more rapidly between these two cosmic epochs. We quantify this effect by computing the value of bL from the SDSS and VVDS clustering amplitudes and find that bL decreases from 1.5±0.2 at z˜0.85 to 1.33±0.03 at z˜0.15, for the most massive galaxies, while it remains virtually constant (b_L˜1.3) for the remaining population. Qualitatively, this is the kind of scenario expected for the clustering of dark-matter halos as a function of their total mass and redshift. Our result therefore seems to indicate that galaxies with the highest stellar mass today were originally central objects of the most massive dark-matter halos at earlier times, whose distribution was strongly biased with respect to the overall mass density field.
The VIMOS-VLT Deep Survey (VVDS). The dependence of clustering on galaxy stellar mass at z ~ 1 / Meneux B.; Guzzo L.; Garilli B.; Le Fèvre O.; Pollo A.; Blaizot J.; De Lucia G.; Bolzonella M.; Lamareille F.; Pozzetti L.; Cappi A.; Iovino A.; Marinoni C.; McCracken H. J.; de La Torre S.; Bottini D.; Le Brun V.; Maccagni D.; Picat J. P.; Scaramella R.; Scodeggio M.; Tresse L.; Vettolani G.; Zanichelli A.; Abbas U.; Adami C.; Arnouts S.; Bardelli S.; Bongiorno A.; Charlot S.; Ciliegi P.; Contini T.; Cucciati O.; Foucaud S.; Franzetti P.; Gavignaud I.; Ilbert O.; Marano B.; Mazure A.; Merighi R.; Paltani S.; Pellò R.; Radovich M.; Vergani D.; Zamorani G.; Zucca E.. - In: ASTRONOMY & ASTROPHYSICS. - ISSN 0004-6361. - STAMPA. - 478:(2008), pp. 299-310. [10.1051/0004-6361:20078182]
The VIMOS-VLT Deep Survey (VVDS). The dependence of clustering on galaxy stellar mass at z ~ 1
CUCCIATI, OLGA;MARANO, BRUNO;VERGANI, DANIELA;
2008
Abstract
Aims.We present a measurement of the dependence of galaxy clustering on galaxy stellar mass at redshift z˜0.9, based on the first-epoch data from the VVDS-Deep survey. Methods: Concentrating on the redshift interval 0.5<z<1.2, we measured the projected correlation function, w_p(r_p), within mass-selected sub-samples covering the range ~109 and ~1011~M_ȯ. We explored and quantify in detail the observational selection biases due to the flux-limited nature of the survey, both from the data themselves and with a suite of realistic mock samples constructed by coupling the Millennium Simulation to semi-analytic models. We identify the range of masses within which our main conclusions are robust against these effects. Serious incompleteness in mass is present below log (M/M_ȯ)=9.5, with about two thirds of the galaxies in the range 9109~M_ȯ to r_0=4.28-0.45+0.43~h-1 Mpc when only the most massive (M>1010.5~M_ȯ) are considered. At the same time, we observe a significant increase in the slope, which over the same range of masses, changes from γ=1.67-0.07+0.08 to γ=2.28-0.27+0.28. Comparison to the SDSS measurements at z˜0.15 shows that the evolution of w_p(r_p) is significant for samples of galaxies with M<1010.5~M_ȯ, while it is negligible for more massive objects. Considering the growth of structure, this implies that the linear bias bL of the most massive galaxies evolves more rapidly between these two cosmic epochs. We quantify this effect by computing the value of bL from the SDSS and VVDS clustering amplitudes and find that bL decreases from 1.5±0.2 at z˜0.85 to 1.33±0.03 at z˜0.15, for the most massive galaxies, while it remains virtually constant (b_L˜1.3) for the remaining population. Qualitatively, this is the kind of scenario expected for the clustering of dark-matter halos as a function of their total mass and redshift. Our result therefore seems to indicate that galaxies with the highest stellar mass today were originally central objects of the most massive dark-matter halos at earlier times, whose distribution was strongly biased with respect to the overall mass density field.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
