Mass and environment as drivers of galaxy evolution in SDSS and zCOSMOS and the origin of the Schechter function
Y. Peng, S. J. Lilly, K. Kovac, M. Bolzonella, L. Pozzetti, A. Renzini, G. Zamorani, O. Ilbert, C. Knobel, A. Iovino, C. Maier, O. Cucciati, L. Tasca, C. M. Car… 展开作者
Y. Peng, S. J. Lilly, K. Kovac, M. Bolzonella, L. Pozzetti, A. Renzini, G. Zamorani, O. Ilbert, C. Knobel, A. Iovino, C. Maier, O. Cucciati, L. Tasca, C. M. Carollo, J. Silverman, P. Kampczyk, L. de Ravel, D. Sanders, N. Scoville, T. Contini, V. Mainieri, M. Scodeggio, J. -P. Kneib, O. Le Fevre, S. Bardelli, A. Bongiorno, K. Caputi, G. Coppa, S. de la Torre, P. Franzetti, B. Garilli, F. Lamareille, J. -F. Le Borgne, V. Le Brun, M. Mignoli, E. Perez Montero, R. Pello, E. Ricciardelli, M. Tanaka, L. Tresse, D. Vergani, N. Welikala, E. Zucca, P. Oesch, U. Abbas, L. Barnes, R. Bordoloi, D. Bottini, A. Cappi, P. Cassata, A. Cimatti, M. Fumana, G. Hasinger, A. M. Koekemoer, A. Leauthaud, D. Maccagni, C. Marinoni, H. J. McCracken, P. Memeo, B. Meneux, P. Nair, C. Porciani, V. Presotto, R. Scaramella
We explore the inter-relationships between mass, star-formation rate and environment in the SDSS, zCOSMOS and other surveys. The differential effects of mass and environment are completely separable to z ~ 1, indicating that two distinct processes are operating, "mass-quenching" and "environment-quenching". Environment-quenching, at fixed over-density, evidently does not change with epoch to z ~ 1, suggesting that it occurs as large-scale structure develops in the Universe. The observed constancy of the mass-function shape for star-forming galaxies, demands that the mass-quenching of galaxies around and above M*, must be proportional to their star-formation rates at all z < 2. We postulate that this simple mass-quenching law also holds over a much broader range of stellar mass and epoch. These two simple quenching processes, plus some additional quenching due to merging, then naturally produce (a) a quasi-static Schechter mass function for star-forming galaxies with a value of M* that is set by the proportionality between the star-formation and mass-quenching rates, (b) a double Schechter function for passive galaxies with two components: the dominant one is produced by mass-quenching and has exactly the same M* as the star-forming galaxies but an alpha shallower by +1, while the other is produced by environment effects and has the same M* and alpha as the star-forming galaxies, and is larger in high density environments. Subsequent merging of quenched galaxies modifies these predictions somewhat in the denser environments, slightly increasing M* and making alpha more negative. All of these detailed quantitative relationships between the Schechter parameters are indeed seen in the SDSS, lending strong support to our simple empirically-based model. The model naturally produces for passive galaxies the "anti-hierarchical" run of mean ages and alpha-element abundances with mass.
The Dependence of Star Formation Activity on Stellar Mass Surface Density and Sersic Index in zCOSMOS Galaxies at 0.5<z<0.9 Compared with SDSS Galaxies at 0.04<z<0.08
The open-data revolution in astronomy is forcing the community to develop sophisticated analysis methods that heavily rely on realistic simulations. The phenomenology of the evolution of galaxy demographics can be described by a set of continuity equations invoking two quenching mechanisms: mass quenching and satellite quenching. The combination of these two mechanisms produces a double Schechter function for the quiescent population, as is observed in the low-redshift universe. In this paper we consider these quenching mechanisms, explicitly including satellite galaxies, and add the exact tim…
Order statistics of the early-type galaxy luminosity function
我们应用顺序统计量(OS)的亮端($M_r < -22$)的光度分布的早期型星系的光谱确定的SDSS DR 7目录。我们计算这种分布的典型OS数量的数值,测量的期望值和方差的$k^{th}$最明亮的星系在一个样本的基数$N$在一个大的合奏这样的样本。从这些统计量,我们解释了为什么和在什么限制$k^{th}$最明亮的星系可以作为标准蜡烛宇宙学研究。由于我们的样本包含所有明亮的星系,包括最亮的星系团(BCG),基于OS,我们认为,BCGs可以被认为是一个完善的Schechter光度分布的统计极值时,星系的红移,而不是集群集群。我们推测这背后的原因可能是星系团中明亮的红色椭圆星系是\em,而不是整体光度分布的随机\em样本,而是由于它们位于包含BCG的星系团中而产生偏差。我们表明,一个简单的统计玩具模型可以重现著名的BCG和第二亮星系团之间的星等差距。
Photometric redshifts are commonly used to measure the distribution of galaxies in large surveys. However, the demands of ongoing and future large-scale cosmology surveys place very stringent limits on the redshift performance that are difficult to meet. A new approach to meet this precision need is forward modelling, which is underpinned by realistic simulations. In the work presented here, we use simulations to study the sensitivity of redshift distributions to the underlying galaxy population demographics. We do this by varying the redshift evolving parameters of the Schechter function for …
The Stellar Mass Function of Gas-Rich Galaxies and the Underlying $M_{\rm HI}-M_{\rm star}$ Scaling Relation in the Local Universe
School of Physical Sciences, National Institute of Science Education and Research(国家科学教育与研究研究所物理科学学院);Homi Bhabha National Institute(霍米·巴巴国立大学);National Centre for Radio Astrophysics, Tata Institute of Fundamental Research(塔塔基础研究院国家射电天文中心)
We introduce a method for producing a galaxy sample unbiased by surface brightness and stellar mass, by selecting star-forming galaxies via the positions of core-collapse supernovae (CCSNe). Whilst matching $\sim$2400 supernovae from the SDSS-II Supernova Survey to their host galaxies using IAC Stripe 82 legacy coadded imaging, we find $\sim$150 previously unidentified low surface brightness galaxies (LSBGs). Using a sub-sample of $\sim$900 CCSNe, we infer CCSN-rate and star-formation rate densities as a function of galaxy stellar mass, and the star-forming galaxy stellar mass function. Result…
We computed the luminosity of simulated galaxies of the C-EAGLE project, a suite of 30 high-resolution zoom-in simulations of galaxy clusters based on the EAGLE simulation. The AB magnitudes are derived for different spectral bands, from ultraviolet to infrared, using the simple stellar population modeling based on the E-MILES stellar spectra library. We take into account obscuration due to dust in star forming regions and diffuse interstellar medium. The $g-r$ colour-stellar mass diagram, at z=0.1, presents a defined red sequence, reaching $g-r \simeq 0.8$, 0.05 dex redder than EAGLE at high …