Kinematics of disk galaxies in (proto-)clusters at z = 1.5

Aims. While many aspects of the impact of dense environments on late-type galaxies at redshifts below unity have been scrutinized in the past few decades, observational studies of the interplay between environment and disk galaxy evolution at z > 1 are still scarce. We observed star-forming galaxies at z ≈ 1.5 selected from the HyperSuprimeCam Subaru Strategic Program. The galaxies are part of two significant overdensities of [O II] emitters identified via narrowband imaging and photometric redshifts from grizy photometry. Methods. We used the K-band Multi-Object Spectrograph (KMOS) to carry out Hα integral field spectroscopy of 46 galaxies in total. Ionized gas maps, star formation rates, and velocity fields were derived from the Hα emission line. We quantified morphological and kinematical asymmetries in order to look for potential gravitational (e.g., galaxy-galaxy) or hydrodynamical (e.g., ram-pressure) interactions. Results. Hα emission was detected in 36 of our targets. Of these galaxies, 34 are members of two (proto-)clusters at z = 1.47, confirming our selection strategy to be highly efficient. By fitting model velocity fields to the observed ones, we determined the intrinsic maximum rotation velocity Vmax of 14 galaxies. Utilizing the luminosity–velocity (Tully–Fisher) relation, we find that these galaxies are more luminous than their local counterparts of similar mass by up to ∼4 mag in the rest-frame B-band. In contrast to field galaxies at z < 1, the offsets of the z ≈ 1.5 (proto-)cluster galaxies from the local Tully–Fisher relation are not correlated with their star formation rates but with the ratio between Vmax and gas velocity dispersion σg. This probably reflects that fewer disks have settled to purely rotational kinematics and high Vmax/σg ratios, as is observed in the field at similar redshifts. Tests with degraded low-redshift cluster galaxy data show that we cannot identify purely hydrodynamical interactions with the imaging currently at hand. Due to relatively low galaxy velocity dispersions (σv < 400 km s−1) of the (proto-)clusters, gravitational interactions are likely more efficient, resulting in higher kinematical asymmetries than in present-days clusters.

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Early-type galaxy formation: understanding the role of the environment

Proceedings of the International Astronomical Union ◽

10.1017/s1743921314009910 ◽

2014 ◽

Vol 10 (S309) ◽

pp. 291-292

Author(s):

Ricardo Demarco ◽

Alessandro Rettura ◽

Chris Lidman ◽

Julie Nantais ◽

Yara Jaffe ◽

...

Keyword(s):

Star Formation ◽

Galaxy Evolution ◽

Galaxy Formation ◽

Early Type ◽

Cluster Galaxy ◽

Cluster Galaxies ◽

Physical Mechanisms ◽

Characteristic Features ◽

Early Type Galaxy

AbstractOne of the most characteristic features of galaxy clusters is the so-called “red sequence” (RS) of early-type galaxies. Since these galaxies are, in general, devoid of gas and dust, their red colors are mainly a consequence of their passive nature. However, the physical mechanisms responsible for quenching their star formation, thus originating the RS, are poorly understood. Environmental effects should play a significant role in the formation of the RS by transforming the observed galaxy properties from late to early-type ones. In this respect, we have initiated a KMOS program aimed at studying the kinematical structure of cluster galaxies at 0.8 < z < 1.7 in an effort to disentangle the physical mechanisms responsible for cluster galaxy evolution and the formation of the RS.

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Galaxy kinematics across different environments in the RXJ1347−1145 cluster complex

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936243 ◽

2020 ◽

Vol 637 ◽

pp. A30

Author(s):

J. M. Pérez-Martínez ◽

B. Ziegler ◽

A. Böhm ◽

M. Verdugo

Keyword(s):

Star Formation ◽

Galaxy Evolution ◽

Formation Rate ◽

Stellar Mass ◽

Cluster Complex ◽

Mass Relation ◽

Cluster Membership ◽

Cluster Galaxies ◽

Fisher Relation

Aims. In order to understand the role of the different processes that drive galaxy evolution in clusters, we need comprehensive studies that simultaneously examine several of the most important physical properties of galaxies. In this work we study the interplay between the kinematic state and star formation activity of galaxies in the RXJ1347−1145 cluster complex at z ∼ 0.45. Methods. We used VLT/VIMOS to obtain slit spectra for 95 galaxies across the 40′ × 40′ area where the RXJ1347−1145 cluster complex resides. We determined the cluster membership of our targets by identifying one or more of the available emission lines within the wavelength range. Our spectroscopy is complemented with archival SUBARU/Suprime-Cam deep photometric observations in five optical bands (B, V, Rc, Ic, z′). We examined the kinematic properties of our sample attending to the degree of distortion of the extracted rotation curves. Regular rotating galaxies were included in our Tully–Fisher analysis while the distorted ones were used to study the role of cluster-specific interactions with respect to star formation and AGN activity. Results. Our analysis confirmed the cluster membership for approximately half of our targets. We report a higher fraction of galaxies with irregular gas kinematics in the cluster environment than in the field. Cluster galaxies with regular rotation display a moderate brightening in the B-band Tully–Fisher relation compatible with the gradual evolution of the stellar populations with lookback time, and no significant evolution in the stellar-mass Tully–Fisher relation, in line with previous studies at similar redshift. Average specific star formation rate values are slightly lower in our cluster sample (−0.15 dex) with respect to the main sequence of star-forming galaxies, confirming the role of the environment in the early quenching of star formation in clusters. Finally, we carried out an exploratory observational study on the stellar-to-halo mass relation finding that cluster galaxies tend to have slightly lower stellar mass values for a fixed halo mass compared to their field counterparts.

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Linking star formation and galaxy kinematics in the massive cluster Abell 2163

Proceedings of the International Astronomical Union ◽

10.1017/s1743921314010242 ◽

2014 ◽

Vol 10 (S309) ◽

pp. 330-330

Author(s):

Veronica Menacho ◽

Miguel Verdugo

Keyword(s):

Star Formation ◽

Galaxy Evolution ◽

Structural Parameters ◽

High Resolution Spectroscopy ◽

Cluster Galaxies ◽

The Galaxy ◽

Galaxy Kinematics ◽

Massive Halos ◽

Fisher Relation ◽

Stellar Masses

AbstractThe origin of the morphology-density relation is still an open question in galaxy evolution. It is most likely driven by the combination of the efficient star formation in the highest peaks of the mass distribution at high-z and the transformation by environmental processes at later times as galaxies fall into more massive halos. To gain additional insights about these processes we study the kinematics, star formation and structural properties of galaxies in Abell 2163 a very massive (~4×1015 M⊙, Holz & Perlmutter 2012) merging cluster at z = 0.2.We use high resolution spectroscopy with VLT/VIMOS to derive rotation curves and dynamical masses for galaxies that show regular kinematics. Galaxies that show irregular rotation are also analysed to study the origin of their distortion. This information is combined with stellar masses and structural parameters obtained from high quality CFHT imaging. From narrow band photometry (2.2m/WFI), centered on the redshifted Hα line, we obtain star formation rates.Although our sample is still small, field and cluster galaxies lie in a similar Tully-Fisher relation as local galaxies. Controlling by additional parameters like SFRs or bulge-to-disk ratio do not affect this result. We find however that ~50% of the cluster galaxies display irregular kinematics in contrast to what is found in the field at similar redshifts (~30%, Böhm et al.2004) and in agreement with other studies in clusters (e.g. Bösch et al.2013, Kutdemir et al.2010) which points out to additional processes operating in clusters that distort the galaxy kinematics.

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Galaxy populations in the most distant SPT-SZ clusters

Astronomy and Astrophysics ◽

10.1051/0004-6361/201833944 ◽

2019 ◽

Vol 622 ◽

pp. A117 ◽

Cited By ~ 15

Author(s):

V. Strazzullo ◽

M. Pannella ◽

J. J. Mohr ◽

A. Saro ◽

M. L. N. Ashby ◽

...

Keyword(s):

Star Formation ◽

Mass Range ◽

Space Telescopes ◽

Cluster Galaxy ◽

Central Regions ◽

Galaxy Populations ◽

Galaxy Population ◽

Stellar Masses ◽

The Impact ◽

Massive Clusters

We present the first results from a galaxy population study in the highest redshift galaxy clusters identified in the 2500 deg2 South Pole Telescope Sunyaev Zel’dovich effect (SPT-SZ) survey, which is sensitive to M500 ≳ 3 × 1014 M⊙ clusters from z ∼ 0.2 out to the highest redshifts where such massive structures exist. The cluster selection is to first order independent of galaxy properties, making the SPT-SZ sample particularly well suited for cluster galaxy population studies. We carried out a four-band imaging campaign with the Hubble and Spitzer Space Telescopes of the five z ≳ 1.4, S/NSZE > 5 clusters, that are among the rarest most massive clusters known at this redshift. All five clusters show clear overdensities of red galaxies whose colors agree with the initial cluster redshift estimates, although one (SPT-CLJ0607–4448) shows a galaxy concentration much less prominent than the others. The highest redshift cluster in this sample, SPT-CLJ0459–4947 at z ∼ 1.72, is the most distant M500 > 1014 M⊙ cluster discovered thus far through its intracluster medium, and is one of only three known clusters in this mass range at z ≳ 1.7, regardless of selection. Based on UVJ-like photometric classification of quiescent and star-forming galaxies, we find that the quiescent fraction in the cluster central regions (r/r500 < 0.7) is higher than in the field at the same redshift, with corresponding environmental quenching efficiencies typically in the range ∼0.5 − 0.8 for stellar masses log(M/M⊙) > 10.85. We have explored the impact of emission from star formation on the selection of this sample, concluding that all five clusters studied here would still have been detected with S/NSZE> 5, even if they had the same quiescent fraction as measured in the field. Our results thus point towards an efficient suppression of star formation in the central regions of the most massive clusters, occurring already earlier than z ∼ 1.5.

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Slow-then-rapid quenching as traced by tentative evidence for enhanced metallicities of cluster galaxies at z ∼ 0.2 in the slow quenching phase

Astronomy and Astrophysics ◽

10.1051/0004-6361/201834290 ◽

2019 ◽

Vol 621 ◽

pp. A131 ◽

Cited By ~ 12

Author(s):

C. Maier ◽

B. L. Ziegler ◽

C. P. Haines ◽

G. P. Smith

Keyword(s):

Star Formation ◽

Large Scale ◽

Rapid Quenching ◽

Cluster Center ◽

Cluster Galaxy ◽

Local Cluster ◽

Cluster Galaxies ◽

Star Forming ◽

The Galaxy ◽

Tentative Evidence

Aims. As large-scale structures in the Universe develop with time, environmental effects become more and more important as a star formation quenching mechanism. Since the effects of environmental quenching are more pronounced in denser structures that form at later times, we seek to constrain environmental quenching processes using cluster galaxies at z < 0.3. Methods. We explored seven clusters from the Local Cluster Substructure Survey (LoCuSS) at 0.15 < z < 0.26 with spectra of 1965 cluster members in a mass-complete sample from the ACReS (Arizona Cluster Redshift Survey) Hectospec survey covering a region that corresponds to about three virial radii for each cluster. We measured fluxes of [O II] λ 3727, Hβ, [O III] λ 5007, Hα, and [N II] λ 6584 emission lines of cluster members, enabling us to unambiguously derive O/H gas metallicities. We also measured star formation rates (SFRs) from extinction-corrected Hα fluxes. We compared our cluster galaxy sample with a field sample of 705 galaxies at similar redshifts observed with Hectospec as part of the same survey. Results. We find that star-forming cluster and field galaxies show similar median specific SFRs in a given mass bin of 1 − 3.2 × 1010 M⊙ and 3.2 − 10 × 1010 M⊙, respectively. But their O/H values are displaced, in the lower mass bin, to higher values (significance 2.4σ) at projected radii of R < R200 compared with galaxies at larger radii and in the field. The comparison with metallicity-SFR-mass model predictions with inflowing gas indicates a slow-quenching scenario in which strangulation is initiated when galaxies pass R ∼ R200 by stopping the inflow of gas. We find tentative evidence that the metallicities of cluster members inside R200 are thereby increasing, but their SFRs are hardly affected for a period of time because these galaxies consume available disk gas. We use the observed fraction of star-forming cluster galaxies as a function of clustercentric radius compared to predictions from the Millennium simulation to constrain quenching timescales to be 1−2 Gyr, which is defined as the time between the moment the galaxy passes R200 until complete quenching of star formation. This is consistent with a slow-then-rapid quenching scenario. Slow quenching (strangulation) starts when the gas inflow is stopped when the galaxy passes R200 with a phase in which cluster galaxies are still star forming, but they show elevated metallicities tracing the ongoing quenching. This phase lasts for 1−2 Gyr, and meanwhile the galaxies travel to denser inner regions of the cluster. This is followed by a “rapid” phase, i.e., a rapid complete quenching of star formation due to the increasing ram pressure toward the cluster center that can also strip the cold gas in massive galaxies.

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The Tully-Fisher relation: evolution with redshift and environment

Proceedings of the International Astronomical Union ◽

10.1017/s1743921306004947 ◽

2006 ◽

Vol 2 (S235) ◽

pp. 8-11 ◽

Cited By ~ 1

Author(s):

Alfonso Aragón-Salamanca

Keyword(s):

Spiral Galaxies ◽

Rotation Velocity ◽

Disk Galaxies ◽

Cluster Galaxies ◽

Fundamental Properties ◽

Look Back ◽

Formation And Evolution ◽

Fisher Relation

AbstractThe Tully-Fisher Relation (TFR) links two fundamental properties of disk galaxies: their luminosity and their rotation velocity (mass). The pioneering work of Vogt et al. in the 1990's showed that it is possible to study the TFR for spiral galaxies at considerable look-back-times, and use it as a powerful probe of their evolution. In recent years, several groups have studied the TFR for galaxies in different environments reaching redshifts beyond one. In this brief review I summarise the main results of some of these studies and their consequences for our understanding of the formation and evolution of disk galaxies. Particular emphasis is placed on the possible environment-driven differences in the behaviour of the TFR for field and cluster galaxies.

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A MUSE inquiry into the physical processes taking place within the Abell 2667 Brightest Cluster Galaxy

Proceedings of the International Astronomical Union ◽

10.1017/s174392131900139x ◽

2019 ◽

Vol 15 (S341) ◽

pp. 83-87

Author(s):

E. Iani ◽

G. Rodighiero ◽

J. Fritz ◽

G. Cresci ◽

C. Mancini ◽

...

Keyword(s):

Star Formation ◽

Formation Rate ◽

Resolving Power ◽

Mass Star ◽

Physical Processes ◽

Cluster Galaxy ◽

Cluster Galaxies ◽

Star Forming ◽

Cold Star ◽

Field Unit

AbstractBrightest cluster galaxies (BCGs) residing in cool-core clusters are known to be the stage of intricate baryon cycle phenomena (e.g. gas inflows, AGN outflows, star formation feedback). The scenarios describing the observed properties of these galaxies are still controversial, suffering from limitations due to the spatial resolving power of the instruments, specifically for galaxies beyond the Local Universe. However, the dramatic improvements introduced by the integral-field unit instruments (e.g. MUSE) could shed light on the physical processes driving the evolution of these galaxies. We present an extensive analysis of the stellar and gas properties (i.e. kinematics, stellar mass, star formation rate) of the radio-loud BCG sitting at the centre of the X-ray luminous cool-core cluster Abell 2667 (z = 0.23), based on MUSE data. Our results indicate that the BCG is a massive elliptical, hosting an AGN that is possibly undergoing accretion of cold star-forming clouds of ICM or galactic cannibalism.

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The Strong Transformation of Spiral Galaxies Infalling into Massive Clusters at z~ 0.2

Proceedings of the International Astronomical Union ◽

10.1017/s1743921306006041 ◽

2006 ◽

Vol 2 (S235) ◽

pp. 198-198

Author(s):

L. Cortese ◽

D. Marcillac ◽

J. Richard ◽

H. Bravo-Alfaro ◽

J.-P. Kneib ◽

...

Keyword(s):

Star Formation ◽

Galaxy Evolution ◽

Hubble Space Telescope ◽

Galactic Disk ◽

Type System ◽

Neutral Hydrogen ◽

Cluster Galaxies ◽

Tidal Interactions ◽

Ram Pressure ◽

Cluster Environment

AbstractWe report the discovery of two peculiar galaxies infalling into the lensing clusters of galaxies Abell 1689 (z~ 0.18) and 2667 (z~ 0.23). Hubble Space Telescope images show extraordinary trails composed by blue bright knots and stellar streams associated with both these systems, an ~L* and ~0.1L* galaxy. Under the combined action of tidal interaction with the cluster potential and of ram pressure by the intra-cluster medium the morphologies and star formation histories of these two galaxies are strongly perturbed. While in the massive system tidal interactions are the dominant effect and are able to produce a sinking of gas towards the galaxy center triggering a strong burst of star formation and changing galaxy's morphology, in the smaller galaxy the effects of gravitation are reduced by ram pressure stripping which blows away the neutral hydrogen from the galactic disk, quenching the star formation activity and transforming a gas rich late type spiral into quiescent disk dominated early type system. This result is a new additional evidence that galaxy mass represents the main driver of galaxy evolution, even during their dive into the harsh cluster environment and can give additional insights on the origin of S0s and dwarf cluster galaxies.

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Spatially resolved dynamics of high-z star forming galaxies

Proceedings of the International Astronomical Union ◽

10.1017/s174392130802735x ◽

2008 ◽

Vol 4 (S254) ◽

pp. 33-34

Author(s):

Reinhard Genzel

Keyword(s):

Star Formation ◽

Galaxy Evolution ◽

Adaptive Optics ◽

Disk Galaxies ◽

Massive Galaxies ◽

Star Forming ◽

Secular Evolution ◽

Spatially Resolved ◽

The Impact ◽

Integral Field

AbstractI report on two major programs to study the kinematic properties of galaxies at z ~ 1.5 − 3 with spatially resolved spectroscopy for the first time. Using the adaptive optics assisted, integral field spectrometer SINFONI on the ESO VLT, we have observed more than 70 galaxies and find compelling evidence for large, geometrically thick (turbulent), rotating disk galaxies in a majority of the objects that we can spatially resolve. It appears that these star forming disks are driven by continuous, rapid accretion of gas from their dark matter halos, and that their evolution is strongly influenced by internal, secular evolution. In contrast to the 20 submillimeter galaxies that we have investigated with the IRAM Plateau de Bure millimetre interferometer we find strong evidence for compact, major mergers. I discuss the impact of these new observations on our understanding of galaxy evolution in the early Universe.For the SINS survey we have carried out Hα integral field spectroscopy of well-resolved, UV/optically selected star-forming galaxies at z ~ 2 with SINFONI on the ESO VLT. The SINS sample is representative of the majority of massive (M* > a few 1010M⊙) star-forming galaxies at that redshift. Our data obtained with laser guide star assisted adaptive optics in good seeing show the presence of turbulent, rotating star-forming rings/disks in at least a third of the sample, plus central bulge/inner disk components in some of the best cases, whose mass fractions relative to total dynamical mass appears to scale with [NII]/Hα flux ratio and ‘star formation’ age. Another third of the SINS galaxies show clear signs of kinematic perturbations by a merger, while the last third appear to be compact, ‘dispersion’ limited systems.Our interpretation of these data is that the buildup of the central disks and bulges of massive galaxies at z ~ 2 can be driven by the early secular evolution of gas-rich ‘proto’-disks. High-redshift disks exhibit large random motions. This turbulence may in part be stirred up by the release of gravitational energy in the rapid ‘cold’ accretion flows along the filaments of the cosmic web. As a result, dynamical friction and viscous processes proceed on a time scale of < 1 Gyr, at least an order of magnitude faster than in disk galaxies at z ~ 0. Early secular evolution thus drives gas and stars into the central regions and can build up exponential disks and massive bulges, even without major mergers. Secular evolution along with increased efficiency of star formation at high surface densities may also help to account for the short time scales of the stellar buildup observed in massive galaxies at z ~ 2.

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J-PLUS: Impact of bars on quenching timescales in nearby green valley disc galaxies

Astronomy and Astrophysics ◽

10.1051/0004-6361/201935138 ◽

2019 ◽

Vol 630 ◽

pp. A88

Author(s):

J. P. Nogueira-Cavalcante ◽

R. Dupke ◽

P. Coelho ◽

M. L. L. Dantas ◽

T. S. Gonçalves ◽

...

Keyword(s):

Star Formation ◽

Galaxy Evolution ◽

Clear Correlation ◽

Spectral Indices ◽

Local Universe ◽

Star Forming ◽

Magnitude Diagram ◽

Star Formation Histories ◽

The Impact ◽

Disc Galaxies

Context. Between the blue cloud and the red sequence peaks on the galaxy colour–magnitude diagram there is a region sparsely populated by galaxies called the green valley. In a framework where galaxies mostly migrate on the colour–magnitude diagram from star forming to quiescent, the green valley is considered a transitional galaxy stage. The details of the processes that drive galaxies from star-forming to passive systems still remain unknown. Aims. We aim to measure the transitional timescales of nearby galaxies across the green valley, through the analysis of Galaxy Evolution Explorer and Javalambre Photometric of Local Universe Survey photometric data. Specifically, we seek to study the impact of bars on the quenching timescales. Methods. We developed a method that estimates empirically the star formation quenching timescales of green valley galaxies, assuming an exponential decay model of the star formation histories and through a combination of narrow and broad bands from the Javalambre Photometric of Local Universe Survey and Galaxy Evolution Explorer. We correlated these quenching timescales with the presence of bars. Results. We find that the Javalambre Photometric of Local Universe Survey colours F0395 −g and F0410 −g are sensitive to different star formation histories, showing, consequently, a clear correlation with the Dn(4000) and Hδ, A spectral indices. We measured quenching timescales based on these colours and we find that quenching timescales obtained with our new approach are in agreement with those determined using spectral indices. We also compared the quenching timescales of green valley disc galaxies as a function of the probability of hosting a bar. We find that galaxies with high bar probability tend to quench their star formation slowly. Conclusions. We conclude that: (1) Javalambre Photometric of Local Universe Survey filters can be used to measure quenching timescales in nearby green valley galaxies; and (2) the resulting star formation quenching timescales are longer for barred green valley galaxies. Considering that the presence of a bar indicates that more violent processes (e.g. major mergers) are absent in host galaxies, we conclude that the presence of a bar can be used as a morphological signature for slow star formation quenching.

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