The HST/ACS Coma Cluster Survey – VII. Structure and assembly of massive galaxies in the centre of the Coma cluster
Tim WeinzirlShardha JogeeEyal NeisteinSadegh KhochfarJohn KormendyIrina MarinovaC. HoyosM. BalcellsMark den BrokD. HammerR. F. PeletierG. Verdoes KleijnDavid CarterPaul GoudfrooijJ. R. LuceyBahram MobasherNeil TrenthamPeter ErwinThomas H. Puzia
24
Citation
233
Reference
10
Related Paper
Citation Trend
Abstract:
We constrain the assembly history of galaxies in the projected central 0.5 Mpc of the Coma cluster by performing structural decomposition on 69 massive (M_star >= 10^9 M_sun) galaxies using high-resolution F814W images from the HST Treasury Survey of Coma. Each galaxy is modeled with up to three Sersic components having a free Sersic index n. After excluding the two cDs in the projected central 0.5 Mpc of Coma, 57% of the galactic stellar mass in the projected central 0.5 Mpc of Coma resides in classical bulges/ellipticals while 43% resides in cold disk-dominated structures. Most of the stellar mass in Coma may have been assembled through major (and possibly minor) mergers. Hubble types are assigned based on the decompositions, and we find a strong morphology-density relation; the ratio of (E+S0):spirals is (91.0%):9.0%. In agreement with earlier work, the size of outer disks in Coma S0s/spirals is smaller compared with lower-density environments captured with SDSS (Data Release 2). Among similar-mass clusters from a hierarchical semi-analytic model, no single cluster can simultaneously match all the global properties of the Coma cluster. The model strongly overpredicts the mass of cold gas and underpredicts the mean fraction of stellar mass locked in hot components over a wide range of galaxy masses. We suggest that these disagreements with the model result from missing cluster physics (e.g., ram-pressure stripping), and certain bulge assembly modes (e.g., mergers of clumps). Overall, our study of Coma underscores that galaxy evolution is not solely a function of stellar mass, but also of environment.Keywords:
Coma Cluster
Coma (optics)
Stellar mass
A growing body of evidence indicates that the star formation rate per unit stellar mass (sSFR) decreases with increasing mass in normal "main-sequence" star forming galaxies. Many processes have been advocated as responsible for such a trend (also known as mass quenching), e.g., feedback from active galactic nuclei (AGNs), and the formation of classical bulges. We determine a refined star formation versus stellar mass relation in the local Universe. To this aim we use the Halpha narrow-band imaging follow-up survey (Halpha3) of field galaxies selected from the HI Arecibo Legacy Fast ALFA Survey (ALFALFA) in the Coma and Local superclusters. By complementing this local determination with high-redshift measurements from the literature, we reconstruct the star formation history of main-sequence galaxies as a function of stellar mass from the present epoch up to z=3. In agreement with previous studies, our analysis shows that quenching mechanisms occur above a threshold stellar mass M_knee that evolves with redshift as propto (1+z)^{2}. Moreover, visual morphological classification of individual objects in our local sample reveals a sharp increase in the fraction of visually-classified strong bars with mass, hinting that strong bars may contribute to the observed downturn in the sSFR above M_knee. We test this hypothesis using a simple but physically-motivated numerical model for bar formation, finding that strong bars can rapidly quench star formation in the central few kpc of field galaxies. We conclude that strong bars contribute significantly to the red colors observed in the inner parts of massive galaxies, although additional mechanisms are likely required to quench the star formation in the outer regions of massive spiral galaxies. Intriguingly, when we extrapolate our model to higher redshifts, we successfully recover the observed redshift evolution for M_knee.
Stellar mass
Cite
Citations (116)
We investigate the relation between star formation rates and local galaxy environment for a stellar mass selected galaxy sample in the redshift range 1.5 < z < 3. We use near-infra-red imaging from an extremely deep Hubble Space Telescope survey, the GOODS-NICMOS Survey (GNS) to measure local galaxy densities based on the nearest neighbour approach, while star-formation rates are estimated from rest-frame UV-fluxes. Due to our imaging depth we can examine galaxies down to a colour-independent stellar mass completeness limit of log M\ast = 9.5 M\odot at z ~ 3. We find a strong dependence of star formation activity on galaxy stellar mass over the whole redshift range, which does not depend on local environment. The average star formation rates are largely independent of local environment apart from in the highest relative over-densities. Galaxies in over-densities of a factor of > 5 have on average lower star formation rates by a factor of 2 - 3, but only up to redshifts of z ~ 2. We do not see any evidence for AGN activity influencing these relations. We also investigate the influence of the very local environment on star-formation activity by counting neighbours within 30 kpc radius. This shows that galaxies with two or more close neighbours have on average significantly lower star formation rates as well as lower specific star formation rates up to z ~ 2.5. We suggest that this might be due to star formation quenching induced by galaxy merging processes.
Stellar mass
Intergalactic star
Cite
Citations (39)
A growing body of evidence indicates that the star formation rate per unit stellar mass (sSFR) decreases with increasing mass in normal main-sequence star-forming galaxies. Many processes have been advocated as being responsible for this trend (also known as mass quenching), e.g., feedback from active galactic nuclei (AGNs), and the formation of classical bulges. In order to improve our insight into the mechanisms regulating the star formation in normal star-forming galaxies across cosmic epochs, we determine a refined star formation versus stellar mass relation in the local Universe. To this end we use the Hα narrow-band imaging followup survey (Hα3) of field galaxies selected from the HI Arecibo Legacy Fast ALFA Survey (ALFALFA) in the Coma and Local superclusters. By complementing this local determination with high-redshift measurements from the literature, we reconstruct the star formation history of main-sequence galaxies as a function of stellar mass from the present epoch up to z = 3. In agreement with previous studies, our analysis shows that quenching mechanisms occur above a threshold stellar mass Mknee that evolves with redshift as ∝(1 + z) 2 . Moreover, visual morphological classification of individual objects in our local sample reveals a sharp increase in the fraction of visually classified strong bars with mass, hinting that strong bars may contribute to the observed downturn in the sSFR above Mknee. We test this hypothesis using a simple but physically motivated numerical model for bar formation, finding that strong bars can rapidly quench star formation in the central few kpc of field galaxies. We conclude that strong bars contribute significantly to the red colors observed in the inner parts of massive galaxies, although additional mechanisms are likely required to quench the star formation in the outer regions of massive spiral galaxies. Intriguingly, when we extrapolate our model to higher redshifts, we successfully recover the observed redshift evolution for Mknee. Our study highlights how the formation of strong bars in massive galaxies is an important mechanism in regulating the redshift evolution of the sSFR for field main-sequence galaxies.
Stellar mass
Cite
Citations (91)
Abstract We investigate the contribution of star formation to the growth of stellar mass in galaxies over the redshift range 0.5 < ɀ < 1.1 by studying the redshift evolution of the specific star formation rate (SSFR), defined as the star formation rate per unit stellar mass. We use an I-band-selected sample of 6180 field galaxies from the Munich Near-Infrared Cluster Survey (MUNICS) with spectroscopically calibrated photometric redshifts. The SSFR decreases with stellar mass at all redshifts. The low SSFRs of massive galaxies indicate that star formation does not significantly change their stellar mass over this redshift range: the majority of massive galaxies have assembled the bulk of their mass before redshift unity. Furthermore, these highest mass galaxies contain the oldest stellar populations at all redshifts. The line of maximum SSFR runs parallel to lines of constant star formation rate. With increasing redshift, the maximum SFR is generally increasing for all stellar masses, from SFR ≃ 5 M⊙ yr−1 at ɀ≃ 0.5 to SFR ≃ 10 M⊙ yr−1 at ɀ ≃ 1.1. We also show that the large SSFRs of low-mass galaxies cannot be sustained over extended periods of time. Finally, our results do not require a substantial contribution of merging to the growth of stellar mass in massive galaxies over the redshift range probed. We note that highly obscured galaxies which remain undetected in our sample do not affect these findings for the bulk of the field galaxy population.
Stellar mass
Cite
Citations (27)
Abstract This paper presents the results of H α imaging of 169 galaxies randomly selected from the α.40 - SDSS catalog. The sample has excluded all low surface brightness galaxies (LSBGs) whose central surface brightness in B band (μ 0 ( B )) fainter than 22.5 mag arcsec −2 . It can be used as the counterparts sample to LSBGs. We observed their H α and R band images by using the 2.16 m telescope at the Xinglong Observatory of the National Astronomical Observatories, Chinese Academy of Sciences (NAOC). The main goal of this work is to present the properties of those galaxies, together with H α flux and star formation-, gas-, stellar mass- surface density. In addition, we confirm the correlations among HI content, stellar mass and star formation in ALFALFA galaxies. The HI mass increases with stellar mass, and the slope slows down at the higher stellar mass. The overall trend was that the specific star formation rate (sSFR) decreases with stellar mass, and the sSFR dropped sharply when the stellar mass is close to 10 10.3 ∼ 10 10.5 M ⊙ . The weak correlation between SFR/M HI and M HI implies the HI contribute little to star formation. Our sample, which are mostly star-forming galaxies, follows the revisited Kennicutt-Schmidt law as well as the Kennicutt-Schmidt law.
Stellar mass
Star (game theory)
Cite
Citations (1)
This paper presents the first results of an Halpha imaging survey of galaxies in the central regions of the A2151 cluster. A total of 50 sources were detected in Halpha. The morphologies of the 43 H$\alpha$ selected galaxies range from grand design spirals and interacting galaxies to blue compacts and tidal dwarfs or isolated extragalactic HII regions, spanning a range of magnitudes of -21 <= MB <= -12.5 mag. A comparison with the clusters Coma and A1367 and a sample of field galaxies has shown the presence of cluster galaxies with L(Halpha) lower than expected for their MB, a consecuence of the cluster environment. This fact results in differences in the L(Halpha) vs. EW(Halpha) and L(H\alpha) distributions of the clusters with respect to the field, and in cluster to cluster variations of these quantities, which we propose are driven by a global cluster property as the total mass. Overall, we conclude that both, the global cluster environment as well as the cluster merging history play a non negligible role in the integral star formation properties of clusters of galaxies.
Coma Cluster
Abell 2744
Cite
Citations (11)
Using the sample from the Redshift One LDSS-3 Emission line Survey (ROLES), we probe the dependence of star formation rate (SFR) and specific star formation rate (sSFR) as a function of stellar mass M* and environment as defined by local galaxy density, in the Chandra Deep Field South field. Our spectroscopic sample consists of 312 galaxies with KAB < 24, corresponding to stellar mass log(M*/M⊙) > 8.5, and with [O ii] derived SFR > 0.3 M⊙ yr−1, at 0.889 ≤z≤ 1.149. The results have been compared directly with the Sloan Digital Sky Survey Stripe 82 sample at 0.032 ≤z≤ 0.05. For star-forming galaxies, we confirm that there is little correlation between SFR and density at z∼ 0. However, for the lowest mass galaxies in our z∼ 1 sample, those with log(M*/M⊙) < 10, we find that both the median SFR and sSFR increase significantly with increasing local density. The 'downsizing' trend for low-mass galaxies to be quenched progressively later in time appears to be more pronounced in moderately overdense environments. Overall we find that the evolution of star formation in galaxies is most strongly driven by their stellar mass, with local galaxy density playing a role that becomes increasingly important for lower mass galaxies.
Stellar mass
Line (geometry)
Cite
Citations (30)
We present a compilation of measurements of the stellar mass density as a function of redshift. Using this stellar mass history we obtain a star formation history and compare it to the instantaneous star formation history. For z < 0.7 there is good agreement between the two star formation histories. At higher redshifts the instantaneous indicators suggest star formation rates larger than that implied by the evolution of the stellar mass density. This discrepancy peaks at z= 3 where instantaneous indicators suggest a star formation rate around 0.6 dex higher than those of the best fit to the stellar mass history. We discuss a variety of explanations for this inconsistency, such as inaccurate dust extinction corrections, incorrect measurements of stellar masses and a possible evolution of the stellar initial mass function.
Stellar mass
Initial mass function
Extinction (optical mineralogy)
Star (game theory)
Cite
Citations (171)
A growing body of evidence indicates that the star formation rate per unit stellar mass (sSFR) decreases with increasing mass in normal star forming galaxies. Many processes have been advocated as responsible for such a trend (also known as mass quenching), e.g., feedback from active galactic nuclei (AGNs), and the formation of classical bulges. We determine a refined star formation versus stellar mass relation in the local Universe. To this aim we use the Halpha narrow-band imaging follow-up survey (Halpha3) of field galaxies selected from the HI Arecibo Legacy Fast ALFA Survey (ALFALFA) in the Coma and Local superclusters. By complementing this local determination with high-redshift measurements from the literature, we reconstruct the star formation history of main-sequence galaxies as a function of stellar mass from the present epoch up to z=3. In agreement with previous studies, our analysis shows that quenching mechanisms occur above a threshold stellar mass M_knee that evolves with redshift as propto (1+z)^{2}. Moreover, visual morphological classification of individual objects in our local sample reveals a sharp increase in the fraction of visually-classified strong bars with mass, hinting that strong bars may contribute to the observed downturn in the sSFR above M_knee. We test this hypothesis using a simple but physically-motivated numerical model for bar formation, finding that strong bars can rapidly quench star formation in the central few kpc of field galaxies. We conclude that strong bars contribute significantly to the red colors observed in the inner parts of massive galaxies, although additional mechanisms are likely required to quench the star formation in the outer regions of massive spiral galaxies. Intriguingly, when we extrapolate our model to higher redshifts, we successfully recover the observed redshift evolution for M_knee.
Stellar mass
Cite
Citations (92)
We present a study of the resolved star-forming properties of a sample of distant massive (M > 1011 M⊙) galaxies in the GOODS NICMOS Survey (GNS), based on deep Hubble Space Telescope imaging from the GOODS North and South fields. We derive dust corrected ultraviolet star formation rates (SFRs) as a function of radius for 45 massive galaxies within the redshift range of 1.5 < z < 3 in order to measure the spatial location of ongoing star formation in massive galaxies. We find that the SFRs present in different regions of a galaxy reflect the already existent stellar mass density, i.e. high-density regions have higher SFRs than lower density regions, on average. This observed star formation is extrapolated in several ways to the present day, and we measure the amount of new stellar mass that is created in individual portions of each galaxy to determine how the stellar mass added via star formation changes the observed stellar mass profile, the Sérsic index and effective radius over time. We find that these massive galaxies fall into three broad classifications of star formation distribution: (1) total stellar mass added via star formation is insignificant compared to the stellar mass that is already in place at high redshift. (2) Stellar mass added via star formation is only significant in the outer regions (R > 1 kpc) of the galaxy. (3) Stellar mass added via star formation is significant in both the inner (R < 1 kpc) and outer regions of the galaxy. These different star formation distributions increase the effective radii over time, which are on average a factor of ∼16 ± 5 per cent larger, with little change in the Sérsic index (average Δn = −0.9 ± 0.9) after evolution. We also implement a range of simple stellar migration models into the simulated evolutionary path of these galaxies in order to gauge its effect on the properties of our sample. This yields a larger increase in the evolved effective radii than the pure static star formation model, with a maximum average increase of ΔRe ∼ 54 ± 19 per cent, but with little change in the Sérsic index, Δn ∼ −1.1 ± 1.3. These results are not in agreement with the observed change in the effective radius and Sérsic index between z ∼ 2.5 and z ∼ 0 obtained via various observational studies. We conclude that star formation and stellar migration alone cannot account for the observed change in structural parameters for this galaxy population, implying that other mechanisms must additionally be at work to produce the evolution, such as merging.
Stellar mass
Intergalactic star
Cite
Citations (14)