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dc.contributor.authorBădescu, Toma
dc.contributor.authorYang, Yujin
dc.contributor.authorBertoldi, Frank
dc.contributor.authorZabludoff, Ann
dc.contributor.authorKarim, Alex
dc.contributor.authorMagnelli, Benjamin
dc.date.accessioned2017-10-03T15:55:58Z
dc.date.available2017-10-03T15:55:58Z
dc.date.issued2017-08-23
dc.identifier.citationDiscovery of a Protocluster Associated with a Ly α Blob Pair at z = 2.3 2017, 845 (2):172 The Astrophysical Journalen
dc.identifier.issn1538-4357
dc.identifier.doi10.3847/1538-4357/aa8220
dc.identifier.urihttp://hdl.handle.net/10150/625775
dc.description.abstractBright Ly alpha blobs (LABs)-extended nebulae with sizes of similar to 100 kpc and Ly alpha luminosities of similar to 10(44) erg s(-1)-often reside in overdensities of compact Ly alpha emitters (LAEs) that may be galaxy protoclusters. The number density, variance, and internal kinematics of LABs suggest that they themselves trace group-like halos. Here, we test this hierarchical picture, presenting deep, wide-field Ly alpha narrowband imaging of a 1 degrees x. 0 degrees.5 region around a LAB pair at z = 2.3 discovered previously by a blind survey. We find 183 Lya emitters, including the original LAB pair and three new LABs with Ly alpha luminosities of (0.9-1.3) x 10(43) erg s(-1) and isophotal areas of 16-24 arcsec2. Using the LAEs as tracers and a new kernel density estimation method, we discover a large-scale overdensity (Bootes J1430+3522) with a surface density contrast of delta(Sigma) = 2.7, a volume density contrast of delta similar to 10.4, and a projected diameter of approximate to 20 comoving Mpc. Comparing with cosmological simulations, we conclude that this LAE overdensity will evolve into a present-day Coma-like cluster with log(M/M-circle dot) similar to 15.1 +/- 0.2. In this and three other wide-field LAE surveys re-analyzed here, the extents and peak amplitudes of the largest LAE overdensities are similar, not increasing with survey size, and implying that they were indeed the largest structures then and today evolve into rich clusters. Intriguingly, LABs favor the outskirts of the densest LAE concentrations, i.e., intermediate LAE overdensities of delta(Sigma) = 1-2. We speculate that these LABs mark infalling protogroups being accreted by the more massive protocluster.
dc.description.sponsorshipBMBF/DLR grant [50 OR 1306]; Basic Science Research Program through the National Research Foundation of Korea (NRF) - Ministry of Science, ICT & Future Planning [NRF-2016R1C1B2007782]; DFG [1573]; Collaborative Research Council - Deutsche Forschungsgemeinschaft (DFG) [956]; NSF [AST-0908280]; NASA [NNX10AD47G]en
dc.language.isoenen
dc.publisherIOP PUBLISHING LTDen
dc.relation.urlhttp://stacks.iop.org/0004-637X/845/i=2/a=172?key=crossref.8e2309e4aee1d5a33461c69905a9669aen
dc.rights© 2017. The American Astronomical Society. All rights reserved.en
dc.subjectgalaxies: clusters: generalen
dc.subjectgalaxies: formationen
dc.subjectgalaxies: high-redshiften
dc.subjectintergalactic mediumen
dc.subjectlarge-scale structure of universeen
dc.titleDiscovery of a Protocluster Associated with a Ly α Blob Pair at z = 2.3en
dc.typeArticleen
dc.contributor.departmentUniv Arizona, Steward Observen
dc.identifier.journalThe Astrophysical Journalen
dc.description.collectioninformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.en
dc.eprint.versionFinal published versionen
refterms.dateFOA2018-09-11T23:26:58Z
html.description.abstractBright Ly alpha blobs (LABs)-extended nebulae with sizes of similar to 100 kpc and Ly alpha luminosities of similar to 10(44) erg s(-1)-often reside in overdensities of compact Ly alpha emitters (LAEs) that may be galaxy protoclusters. The number density, variance, and internal kinematics of LABs suggest that they themselves trace group-like halos. Here, we test this hierarchical picture, presenting deep, wide-field Ly alpha narrowband imaging of a 1 degrees x. 0 degrees.5 region around a LAB pair at z = 2.3 discovered previously by a blind survey. We find 183 Lya emitters, including the original LAB pair and three new LABs with Ly alpha luminosities of (0.9-1.3) x 10(43) erg s(-1) and isophotal areas of 16-24 arcsec2. Using the LAEs as tracers and a new kernel density estimation method, we discover a large-scale overdensity (Bootes J1430+3522) with a surface density contrast of delta(Sigma) = 2.7, a volume density contrast of delta similar to 10.4, and a projected diameter of approximate to 20 comoving Mpc. Comparing with cosmological simulations, we conclude that this LAE overdensity will evolve into a present-day Coma-like cluster with log(M/M-circle dot) similar to 15.1 +/- 0.2. In this and three other wide-field LAE surveys re-analyzed here, the extents and peak amplitudes of the largest LAE overdensities are similar, not increasing with survey size, and implying that they were indeed the largest structures then and today evolve into rich clusters. Intriguingly, LABs favor the outskirts of the densest LAE concentrations, i.e., intermediate LAE overdensities of delta(Sigma) = 1-2. We speculate that these LABs mark infalling protogroups being accreted by the more massive protocluster.


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