scholarly journals Measuring the total infrared light from galaxy clusters at z = 0.5–1.6: connecting stellar populations to dusty star formation

2020 ◽  
Vol 501 (2) ◽  
pp. 1970-1998
Author(s):  
Stacey Alberts ◽  
Kyoung-Soo Lee ◽  
Alexandra Pope ◽  
Mark Brodwin ◽  
Yi-Kuan Chiang ◽  
...  

ABSTRACT Massive galaxy clusters undergo strong evolution from z ∼ 1.6 to z ∼ 0.5, with overdense environments at high-z characterized by abundant dust-obscured star formation and stellar mass growth which rapidly give way to widespread quenching. Data spanning the near- to far-infrared (IR) can directly trace this transformation; however, such studies have largely been limited to the massive galaxy end of cluster populations. In this work, we present ‘total light’ stacking techniques spanning $3.4\!-\!500\, \mu$m aimed at revealing the total cluster emission, including low-mass members and potential intracluster dust. We detail our procedures for WISE, Spitzer, and Herschel imaging, including corrections to recover the total stacked emission in the case of high fractions of detected galaxies. We apply our techniques to 232 well-studied log$\, M_{200}/\mathrm{M}_{\odot }\sim 13.8$ clusters in multiple redshift bins, recovering extended cluster emission at all wavelengths. We measure the averaged IR radial profiles and spectral energy distributions (SEDs), quantifying the total stellar and dust content. The near-IR profiles are well described by an NFW model with a high (c ∼ 7) concentration. Dust emission is similarly concentrated, albeit suppressed at $r\lesssim 0.3\,$Mpc. The measured SEDs lack warm dust, consistent with the colder SEDs of low-mass galaxies. We derive total stellar masses consistent with the theoretical Mhalo−M⋆ relation and specific star formation rates that evolve strongly with redshift, echoing that of log$\, M_{\star }/\mathrm{M}_{\odot }\gtrsim 10$ cluster galaxies. Separating out the massive population reveals the majority of cluster far-IR emission ($\sim 70\!-\!80{{\ \rm per\ cent}}$) is provided by the low-mass constituents, which differs from field galaxies. This effect may be a combination of mass-dependent quenching and excess dust in low-mass cluster galaxies.

2009 ◽  
Vol 5 (H15) ◽  
pp. 88-88
Author(s):  
Roberto P. Muñoz ◽  
L. F. Barrientos ◽  
B. P. Koester ◽  
D. G. Gilbank ◽  
M. D. Gladders ◽  
...  

AbstractWe use deep nIR imaging of 15 galaxy clusters at z ≃ 1 to study the build-up of the red-sequence in rich clusters since the Universe was half its present age. We measured, for the first time, the luminous-to-faint ratio of red-sequence galaxies at z=1 from a large ensemble of clusters, and found an increase of 100% in the ratio of luminous-to-faint red-sequence galaxies from z=0.45 to 1.0. The measured change in this ratio as function of redshift is well-reproduced by a simple evolutionary model developed in this work, that consists in an early truncation of the star formation for bright cluster galaxies and a delayed truncation for faint cluster galaxies.


2017 ◽  
Vol 604 ◽  
pp. A52 ◽  
Author(s):  
A. Bracco ◽  
P. Palmeirim ◽  
Ph. André ◽  
R. Adam ◽  
P. Ade ◽  
...  

The characterization of dust properties in the interstellar medium is key for understanding the physics and chemistry of star formation. Mass estimates are crucial to determine gravitational collapse conditions for the birth of new stellar objects in molecular clouds. However, most of these estimates rely on dust models that need further observational constraints to capture the relevant parameter variations depending on the local environment: from clouds to prestellar and protostellar cores. We present results of a new study of dust emissivity changes based on millimeter continuum data obtained with the NIKA camera at the IRAM-30 m telescope. Observing dust emission at 1.15 mm and 2 mm allows us to constrain the dust emissivity index, β, in the Rayleigh-Jeans tail of the dust spectral energy distribution far from its peak emission, where the contribution of other parameters (i.e. dust temperature) is more important. Focusing on the Taurus molecular cloud, one of the most famous low-mass star-forming regions in the Gould Belt, we analyze the emission properties of several distinct objects in the B213 filament. This subparsec-sized region is of particular interest since it is characterized by a collection ofevolutionary stages of early star formation: three prestellar cores, two Class 0/I protostellar cores and one Class II object. We are therefore able to compare dust properties among a sequence of sources that likely derive from the same parent filament. By means of the ratio of the two NIKA channel maps, we show that in the Rayleigh-Jeans approximation, βRJ varies among the objects: it decreases from prestellar cores (βRJ ~ 2) to protostellar cores (βRJ ~ 1) and the Class II object (βRJ ~ 0). For one prestellar and two protostellar cores, we produce a robust study using available Herschel data to constrain the dust temperature of the sources. By using the Abel transform inversion technique we derive accurate radial temperature profiles that allow us to obtain radial β profiles. We find systematic spatial variations of β in the protostellar cores that are not observed in the prestellar core. While in the former case β decreases toward the center (with β varying between 1 and 2), in the latter it remains constant (β = 2.4 ± 0.3). Moreover, the dust emissivity index appears anticorrelated with the dust temperature. We discuss the implication of these results in terms of dust grain evolution between pre- and protostellar cores.


2019 ◽  
Vol 631 ◽  
pp. A38 ◽  
Author(s):  
S. Lianou ◽  
P. Barmby ◽  
A. A. Mosenkov ◽  
M. Lehnert ◽  
O. Karczewski

Aims. We derived the dust properties for 753 local galaxies and examine how these relate to some of their physical properties. We present the derived dust emission properties, including model spectral energy distribution (SEDs), star formation rates (SFRs) and stellar masses, as well as their relations. Methods. We modelled the global dust-SEDs for 753 galaxies, treated statistically as an ensemble within a hierarchical Bayesian dust-SED modelling approach, so as to derive their infrared (IR) emission properties. To create the observed dust-SEDs, we used a multi-wavelength set of observations, ranging from near-IR to far-IR-to-submillimeter wavelengths. The model-derived properties are the dust masses (Mdust), the average interstellar radiation field intensities (Uav), the mass fraction of very small dust grains (“QPAH” fraction), as well as their standard deviations. In addition, we used mid-IR observations to derive SFR and stellar masses, quantities independent of the dust-SED modelling. Results. We derive distribution functions of the properties for the galaxy ensemble and as a function of galaxy type. The mean value of Mdust for the early-type galaxies (ETGs) is lower than that for the late-type and irregular galaxies (LTGs and Irs, respectively), despite ETGs and LTGs having stellar masses spanning across the whole range observed. The Uav and “QPAH” fraction show no difference among different galaxy types. When fixing Uav to the Galactic value, the derived “QPAH” fraction varies across the Galactic value (0.071). The specific SFR increases with galaxy type, while this is not the case for the dust-specific SFR (SFR/Mdust), showing an almost constant star formation efficiency per galaxy type. The galaxy sample is characterised by a tight relationship between the dust mass and the stellar mass for the LTGs and Irs, while ETGs scatter around this relation and tend towards smaller dust masses. While the relation indicates that Mdust may fundamentally be linked to M⋆, metallicity and Uav are the second parameter driving the scatter, which we investigate in a forthcoming work. We used the extended Kennicutt–Schmidt (KS) law to estimate the gas mass and the gas-to-dust mass ratio (GDR). The gas mass derived from the extended KS law is on average ∼20% higher than that derived from the KS law, and a large standard deviation indicates the importance of the average star formation present to regulate star formation and gas supply. The average GDR for the LTGs and Irs is 370, and including the ETGs gives an average of 550.


2018 ◽  
Vol 14 (S342) ◽  
pp. 145-148
Author(s):  
Elias Koulouridis ◽  

AbstractWe present the results of a study of the AGN density in a homogeneous and well studied sample of 167 bona-fide X-ray galaxy clusters (0.1<z<0.5). Our aim is to study the AGN activity in 167 XXL X-ray galaxy clusters as a function of the cluster mass and the location of the AGN in the cluster. We report a significant AGN excess in our low-mass cluster sub-sample between 0.5r500 and 2r500. In contrast, the high-mass sub-sample presents no AGN excess. The AGN excess in poor clusters indicates AGN triggering, supporting previous studies that reported enhanced galaxy merging in the cluster outskirts. This effect is probably prevented by high velocity dispersions in high-mass clusters. Comparing also with previous studies of massive or high-redshift clusters, we conclude that the AGN fraction in cluster galaxies anti-correlates strongly with cluster mass.


2011 ◽  
Vol 7 (S284) ◽  
pp. 97-100
Author(s):  
George J. Bendo ◽  

AbstractWe use Herschel Space Observatory and Spitzer Space Telescope 70-500 μm data along with ground-based optical and near-infrared data to understand how dust heating in the nearby face-on spiral galaxies M81, M83, and NGC 2403 is affected by the starlight from all stars and by the radiation from star-forming regions. We find that 70/160 μm flux density ratios tend to be more strongly influenced by star-forming regions. However, the 250/350 and 350/500 μm micron flux density ratios are more strongly affected by the light from the total stellar populations, suggesting that the dust emission at > 250 μm originates predominantly from a component that is colder than the dust seen at <160 μm and that is relatively unaffected by star formation activity. We conclude by discussing the implications of this for modelling the spectral energy distributions of both nearby and more distant galaxies and for using far-infrared dust emission to trace star formation.


2021 ◽  
Vol 923 (2) ◽  
pp. 215
Author(s):  
Caitlin M. Casey ◽  
Jorge A. Zavala ◽  
Sinclaire M. Manning ◽  
Manuel Aravena ◽  
Matthieu Béthermin ◽  
...  

Abstract We present the characteristics of 2 mm selected sources from the largest Atacama Large Millimeter/submillimeter Array (ALMA) blank-field contiguous survey conducted to date, the Mapping Obscuration to Reionization with ALMA (MORA) survey covering 184 arcmin2 at 2 mm. Twelve of 13 detections above 5σ are attributed to emission from galaxies, 11 of which are dominated by cold dust emission. These sources have a median redshift of 〈 z 2 mm 〉 = 3.6 − 0.3 + 0.4 primarily based on optical/near-infrared photometric redshifts with some spectroscopic redshifts, with 77% ± 11% of sources at z > 3 and 38% ± 12% of sources at z > 4. This implies that 2 mm selection is an efficient method for identifying the highest-redshift dusty star-forming galaxies (DSFGs). Lower-redshift DSFGs (z < 3) are far more numerous than those at z > 3 yet are likely to drop out at 2 mm. MORA shows that DSFGs with star formation rates in excess of 300 M ⊙ yr−1 and a relative rarity of ∼10−5 Mpc−3 contribute ∼30% to the integrated star formation rate density at 3 < z < 6. The volume density of 2 mm selected DSFGs is consistent with predictions from some cosmological simulations and is similar to the volume density of their hypothesized descendants: massive, quiescent galaxies at z > 2. Analysis of MORA sources’ spectral energy distributions hint at steeper empirically measured dust emissivity indices than reported in typical literature studies, with 〈 β 〉 = 2.2 − 0.4 + 0.5 . The MORA survey represents an important step in taking census of obscured star formation in the universe’s first few billion years, but larger area 2 mm surveys are needed to more fully characterize this rare population and push to the detection of the universe’s first dusty galaxies.


2020 ◽  
Vol 496 (1) ◽  
pp. 442-455 ◽  
Author(s):  
Kshitija Kelkar ◽  
K S Dwarakanath ◽  
Bianca M Poggianti ◽  
Alessia Moretti ◽  
Rogério Monteiro-Oliveira ◽  
...  

ABSTRACT We present a detailed analysis of star formation properties of galaxies in a nearby (z ∼ 0.046) young (∼0.6 Gyr) post-merger cluster system A3376, with a moderate merger shock front (vs ∼1630 km s−1; $\mathcal {M}$ ∼ 2) observed as symmetric radio relics. Exploiting the spectroscopic data from the wide-field OmegaWINGS survey and the associated photometric information, our investigations reveal the plausible effects of the dynamic post-merger environment differing from the high-density cluster environment experienced prior to the merging activity. The remnants of the pre-merger relaxed cluster environment are realized through the existence of passive spiral galaxies located in the central regions of the cluster between the two brightest cluster galaxies. We discover A3376 to contain a population of massive (log (M*/M⊙) &gt; 10) blue regular star-forming spirals in regions of maximum merger shock influence but exhibiting star formation rates similar to those in relaxed clusters at similar epoch. We further discover low-mass (log (M*/M⊙) ≤ 10) late-type blue post-starburst galaxies which could either be formed as a result of rapid quenching of low-mass spirals following the shock-induced star formation or due to the intense surge in the intracluster medium pressures at the beginning of the merger. With the possibility of the merger shock affecting high- and low-mass spirals differently, our results bridge the seemingly contradictory results observed in known merging cluster systems so far and establish that different environmental effects are at play right from pre- to post-merger stages.


2019 ◽  
Vol 488 (1) ◽  
pp. 847-858 ◽  
Author(s):  
Diego Pallero ◽  
Facundo A Gómez ◽  
Nelson D Padilla ◽  
S Torres-Flores ◽  
R Demarco ◽  
...  

ABSTRACT We use the Evolution and Assembly of GaLaxies and their Environments (EAGLE) hydrodynamical simulation to trace the quenching history of galaxies in its 10 most massive clusters. We use two criteria to identify moments when galaxies suffer significant changes in their star formation activity: (i) the instantaneous star formation rate (SFR) strongest drop, $\Gamma _{\rm SFR}^{\rm SD}$, and (ii) a ‘quenching’ criterion based on a minimum threshold for the specific SFR of ≲10$^{-11}\,\rm yr^{-1}$. We find that a large fraction of galaxies (${\gtrsim} 60\,{\rm per\,cent}$) suffer their $\Gamma _{\rm SFR}^{\rm SD}$ outside the cluster’s R200. This ‘pre-processed’ population is dominated by galaxies that are either low mass and centrals or inhabit low-mass hosts (1010.5 ≲ Mhost ≲ 1011.0 M⊙). The host mass distribution is bimodal, and galaxies that suffered their $\Gamma _{\rm SFR}^{\rm SD}$ in massive hosts ($10^{13.5} \lesssim M_{\rm host} \lesssim 10^{14.0}\, \mathrm{M}_{\odot }$) are mainly processed within the clusters. Pre-processing mainly limits the total stellar mass with which galaxies arrive in the clusters. Regarding quenching, galaxies preferentially reach this state in high-mass haloes ($10^{13.5} \lesssim M_{\rm host} \lesssim 10^{14.5}\, \mathrm{M}_{\odot }$). The small fraction of galaxies that reach the cluster already quenched have also been pre-processed, linking both criteria as different stages in the quenching process of those galaxies. For the z = 0 satellite populations, we find a sharp rise in the fraction of quenched satellites at the time of first infall, highlighting the role played by the dense cluster environment. Interestingly, the fraction of pre-quenched galaxies rise with final cluster mass. This is a direct consequence of the hierarchical cosmological model used in these simulations.


2019 ◽  
Vol 625 ◽  
pp. A148
Author(s):  
Julien Dassa-Terrier ◽  
Anne-Laure Melchior ◽  
Françoise Combes

We analysed molecular observations performed at IRAM interferometer in CO(1-0) of the circum-nuclear region (within 250 pc) of Andromeda with 2.9″ = 11 pc resolution. We detected 12 molecular clumps in this region, corresponding to a total molecular mass of (8.4 ± 0.4)×104 M⊙. These clumps follow Larson’s mass-size relation, but lie well above the velocity-size relation. We discuss the possibility that these clumps are probably not virialised, but are transient agglomerations of smaller entities that might be virialised. Three of these clumps have been detected in CO(2-1) in a previous work, and we find a temperature line ratio below 0.5 in this work. With a radiative transfer analysis, we show that this gas is in non-local thermal equilibrium with a low excitation temperature (Tex = 5 − 9 K). We find a surface beam filling factor of order 5% and a gas density in the range 60 − 650 cm−3, which is well below the critical density. With a gas-to-stellar mass fraction of 4 × 10−4 and dust-to-gas ratio of 0.01, this quiescent region has exhausted its gas budget. Its spectral energy distribution is compatible with passive templates assembled from elliptical galaxies. While weak dust emission is present in the region, we show that no star formation is present and support the previous results that the dust is heated by the old and intermediate stellar population. We study the possibility that this region lies formally in the low-density part of the Kennicutt-Schmidt law in a regime where the star formation rate estimators are not completely reliable. We confirm the quiescence of the inner part of this galaxy known to lie on the green valley.


1996 ◽  
Vol 171 ◽  
pp. 349-349
Author(s):  
N. Cardiel ◽  
J. Gorgas ◽  
A. Aragon-Salamanca

X-ray observations have led to the conclusion that many galaxy clusters are hosting cooling flows. The brightest cluster galaxies could have accreted masses of the order of 1011–1012M⊙, but is still uncertain what the final fate of the accreted gas may be.


Sign in / Sign up

Export Citation Format

Share Document