Evidence for a Massive Poststarburst Galaxy at<i>z</i> ∼ 6.5

Mobasher, Bahram; Dickinson, Mark; Ferguson, Harry; Giavalisco, Mauro; Wiklind, T.; Stark, Daniel P.; Ellis, Richard S.; Fall, S. Michael; Grogin, Norman A.; Moustakas, Leonidas A.; Panagia, N.; Sosey, M.; Stiavelli, M.; Bergeron, E.; Casertano, Stefano; Ingraham, Patrick; Koekemoer, Anton M.; Labbé, Ivo; Livio, Mario; Rodgers, Bernadette; Scarlata, Claudia; Vernet, J.; Renzini, A.; Rosati, P.; Küntschner, H.; Kümmel, M.; Walsh, J. R.; Chary, R.-R.; Eisenhardt, Peter; Pirzkal, Norbert; Stern, Daniel

doi:10.1086/497626

Cited by 136 publications

(192 citation statements)

References 56 publications

Supporting

Mentioning

180

Contrasting

Order By: Relevance

“…13 we note that with (I − J) > 5.4 and 4.4 and (z − J) > 3.9 and 3.1 for z1 and Y5, both sources show extreme (very red) optical-to-near-IR colors, when compared to other low-redshift galaxies with red (J − z) colors. z1 and Y5 are also similar to the z-dropout galaxy HUDF-J2 identified by Mobasher et al (2005) as a z ≈ 6.5 post-starburst galaxy candidate, but later shown to be most likely at z ∼ 1.8-2.5 interloper by Schaerer et al (2007); Dunlop et al (2007);Chary et al (2007). Although similar in several respects, HUDF-J2 shows a more monotonously rising SED between z, J, and H than our objects exhibiting a "sharper" break.…”

Section: Comparison With Other Objects In the Literaturesupporting

confidence: 74%

“…Objects such as these have been found and discussed by several authors (see e.g. Dickinson et al 2000;Mobasher et al 2005;Schaerer et al 2007;Dunlop et al 2007;Chary et al 2007;Capak et al 2011). Confirming the photometric redshifts of high-z galaxies by identifying spectral lines is challenging because the sources are generally too faint for spectroscopic follow-up observations or because they may intrinsically lack Lyα emission (but see Vanzella et al 2011).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Far-infrared constraints on the contamination by dust-obscured galaxies of high-zdropout searches

Boone¹,

Pelló²,

Lutz³

et al. 2011

A&A

View full text Add to dashboard Cite

The spectral energy distributions (SED) of dusty galaxies at intermediate redshift may look similar to very high-redshift galaxies in the optical/near infrared (NIR) domain. This can lead to the contamination of high-redshift galaxy searches based on broad-band optical/NIR photometry by lower redshift dusty galaxies because both kind of galaxies cannot be distinguished. The contamination rate could be as high as 50%. This work shows how the far-infrared (FIR) domain can help to recognize likely low-z interlopers in an optical/NIR search for high-z galaxies. We analyze the FIR SEDs of two galaxies that are proposed to be very high-redshift (z > 7) dropout candidates based on deep Hawk-I/VLT observations. The FIR SEDs are sampled with PACS/Herschel at 100 and 160 μm, with SPIRE/Herschel at 250, 350 and 500 μm and with LABOCA/APEX at 870 μm. We find that redshifts >7 would imply extreme FIR SEDs (with dust temperatures >100 K and FIR luminosities >10 13 L ). At z ∼ 2, instead, the SEDs of both sources would be compatible with those of typical ultra luminous infrared galaxies or submillimeter galaxies. Considering all available data for these sources from visible to FIR we re-estimate the redshifts and find z ∼ 1.6-2.5. Owing to the strong spectral breaks observed in these galaxies, standard templates from the literature fail to reproduce the visible-to-near-IR part of the SEDs even when additional extinction is included. These sources strongly resemble dust-obscured galaxies selected in Spitzer observations with extreme visibleto-FIR colors, and the galaxy GN10 at z = 4. Galaxies with similar SEDs could contaminate other high-redshift surveys.

show abstract

Section: Comparison With Other Objects In the Literaturesupporting

confidence: 74%

Section: Introductionmentioning

confidence: 99%

Far-infrared constraints on the contamination by dust-obscured galaxies of high-zdropout searches

Boone¹,

Pelló²,

Lutz³

et al. 2011

A&A

View full text Add to dashboard Cite

show abstract

“…These are the locations of the formation of the first objects in the Universe (e.g. Venemans et al 2004;Mobasher et al 2005;Ouchi et al 2005). Observations have already found superclusters at high redshifts (Nakata et al 2005;Swinbank et al 2007;Gal et al 2008;Tanaka et al 2009).…”

Section: Introductionmentioning

confidence: 98%

SDSS DR7 superclusters

Einasto

Liivamägi

Tago

et al. 2011

A&A

122

View full text Add to dashboard Cite

Aims. We study the morphology of a set of superclusters drawn from the SDSS DR7. Methods. We calculate the luminosity density field to determine superclusters from a flux-limited sample of galaxies from SDSS DR7 and select superclusters with 300 and more galaxies for our study. We characterise the morphology of superclusters using the fourth Minkowski functional V 3 , the morphological signature (the curve in the shapefinder's K 1 -K 2 plane) and the shape parameter (the ratio of the shapefinders K 1 /K 2 ). We investigate the supercluster sample using multidimensional normal mixture modelling. We use Abell clusters to identify our superclusters with known superclusters and to study the large-scale distribution of superclusters. Results. The superclusters in our sample form three chains of superclusters; one of them is the Sloan Great Wall. Most superclusters have filament-like overall shapes. Superclusters can be divided into two sets; more elongated superclusters are more luminous, richer, have larger diameters and a more complex fine structure than less elongated superclusters. The fine structure of superclusters can be divided into four main morphological types: spiders, multispiders, filaments, and multibranching filaments. We present the 2D and 3D distribution of galaxies and rich groups, the fourth Minkowski functional, and the morphological signature for all superclusters. Conclusions. Widely different morphologies of superclusters show that their evolution has been dissimilar. A study of a larger sample of superclusters from observations and simulations is needed to understand the morphological variety of superclusters and the possible connection between the morphology of superclusters and their large-scale environment.

show abstract

“…The formation of rich superclusters had to begin earlier than that of the smaller structures; they are the sites of early star and galaxy formation (e.g. Mobasher et al 2005), and the first places where systems of galaxies form (e.g. Venemans et al 2004;Ouchi et al 2005).…”

Section: Introductionmentioning

confidence: 99%

The Sloan great wall. Rich clusters

Einasto

Tago

Saar

et al. 2010

A&A

View full text Add to dashboard Cite

Aims. We present the results of the study of the substructure and galaxy content of ten rich clusters of galaxies in three different superclusters of the Sloan great wall, the richest nearby system of galaxies (hereafter SGW). Methods. We determine the substructure in clusters using the "Mclust" package from the "R" statistical environment and analyse their galaxy content with information about colours and morphological types of galaxies. We analyse the distribution of the peculiar velocities of galaxies in clusters and calculate the peculiar velocity of the first ranked galaxy. Results. We show that five clusters in our sample have more than one component; in some clusters the different components also have different galaxy content. In other clusters there are distinct components in the distribution of the peculiar velocities of galaxies. We find that in some clusters with substructure the peculiar velocities of the first ranked galaxies are high. All clusters in our sample host luminous red galaxies; in eight clusters their number exceeds ten. Luminous red galaxies can be found both in the central areas of clusters and in the outskirts, some of them have high peculiar velocities. About 1/3 of the red galaxies in clusters are spirals. The scatter of colours of red ellipticals is in most clusters larger than that of red spirals. The fraction of red galaxies in rich clusters in the cores of the richest superclusters is larger than the fraction of red galaxies in other very rich clusters in the SGW. Conclusions. The presence of substructure in rich clusters, signs of possible mergers and infall, and the high peculiar velocities of the first ranked galaxies suggest that the clusters in our sample are not yet virialized. We present merger trees of dark matter haloes in an N-body simulation to demonstrate the formation of present-day dark matter haloes via multiple mergers during their evolution. In simulated dark matter haloes we find a substructure similar to that in observed clusters.

show abstract

Evidence for a Massive Poststarburst Galaxy atz ∼ 6.5

Cited by 136 publications

References 56 publications

Far-infrared constraints on the contamination by dust-obscured galaxies of high-zdropout searches

Far-infrared constraints on the contamination by dust-obscured galaxies of high-zdropout searches

SDSS DR7 superclusters

The Sloan great wall. Rich clusters

Contact Info

Product

Resources

About