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dc.contributor.authorCai, Zheng
dc.contributor.authorFan, Xiaohui
dc.contributor.authorPeirani, Sebastien
dc.contributor.authorBian, Fuyan
dc.contributor.authorFrye, Brenda
dc.contributor.authorMcGreer, Ian D.
dc.contributor.authorProchaska, J. Xavier
dc.contributor.authorLau, Marie Wingyee
dc.contributor.authorTejos, Nicolas
dc.contributor.authorHo, Shirley
dc.contributor.authorSchneider, Donald P.
dc.date.accessioned2017-03-01T22:47:29Z
dc.date.available2017-03-01T22:47:29Z
dc.date.issued2016-12-13
dc.identifier.citationMAPPING THE MOST MASSIVE OVERDENSITY THROUGH HYDROGEN (MAMMOTH). I. METHODOLOGY 2016, 833 (2):135 The Astrophysical Journalen
dc.identifier.issn1538-4357
dc.identifier.doi10.3847/1538-4357/833/2/135
dc.identifier.urihttp://hdl.handle.net/10150/622671
dc.description.abstractModern cosmology predicts that a galaxy overdensity (e.g., protocluster) will be associated with a large intergalactic medium gas reservoir, which can be traced by Ly alpha forest absorption. We have undertaken a systematic study of the relation between Coherently Strong intergalactic Lya Absorption systems (CoSLAs), which have the highest optical depth (tau) in the tau distribution, and mass overdensities on the scales of similar to 10-20 h(-1) comoving Mpc. On such large scales, our cosmological simulations show a strong correlation between the effective optical depth (tau(eff)) of the CoSLAs and the three-dimensional mass overdensity. In spectra with moderate signal-to-noise ratio, however, the profiles of CoSLAs can be confused with individual high column density absorbers. For z > 2.6, where the corresponding Ly beta is redshifted to the optical, we have developed a selection technique to distinguish between these two alternatives. We have applied this technique to similar to 6000 sight lines provided by Sloan Digital Sky Survey III quasar survey at z = 2.6-3.3 with a continuum-to-noise ratio greater than 8, and we present a sample of five CoSLA candidates with tau(eff) on 15 h(-1) Mpc greater than 4.5x the mean optical depth. At lower redshifts of z < 2.6, where the background quasar density is higher, the overdensity can be traced by intergalactic absorption groups using multiple sight lines with small angular separations. Our overdensity searches fully use the current and next generation of Ly alpha forest surveys, which cover a survey volume of > 1 (h(-1) Gpc)(3). Systems traced by CoSLAs will yield a uniform sample of the most massive overdensities at z > 2 to provide stringent constraints to models of structure formation.
dc.description.sponsorshipUS NSF grant [AST 11-07682]; NSF [AST-1412981]; Alfred P. Sloan Foundation; National Science Foundation; U.S. Department of Energy Office of Science; University of Arizona; Brazilian Participation Group; Brookhaven National Laboratory; University of Cambridge; Carnegie Mellon University; University of Florida; French Participation Group; German Participation Group; Harvard University; Instituto de Astrofisica de Canarias; Michigan State/Notre Dame/JINA Participation Group; Johns Hopkins University; Lawrence Berkeley National Laboratory; Max Planck Institute for Astrophysics; Max Planck Institute for Extraterrestrial Physics; New Mexico State University; New York University; Ohio State University; Pennsylvania State University; University of Portsmouth; Princeton University; Spanish Participation Group; University of Tokyo; University of Utah; Vanderbilt University; University of Virginia; University of Washington; Yale Universityen
dc.language.isoenen
dc.publisherIOP PUBLISHING LTDen
dc.relation.urlhttp://stacks.iop.org/0004-637X/833/i=2/a=135?key=crossref.7ff191206b1859c01072ef7e75d98834en
dc.rights© 2016. The American Astronomical Society. All rights reserved.en
dc.subjectgalaxies: high-redshiften
dc.subjectintergalactic mediumen
dc.subjectquasars: absorption linesen
dc.titleMAPPING THE MOST MASSIVE OVERDENSITY THROUGH HYDROGEN (MAMMOTH). I. METHODOLOGYen
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.dateFOA2018-07-06T02:52:11Z
html.description.abstractModern cosmology predicts that a galaxy overdensity (e.g., protocluster) will be associated with a large intergalactic medium gas reservoir, which can be traced by Ly alpha forest absorption. We have undertaken a systematic study of the relation between Coherently Strong intergalactic Lya Absorption systems (CoSLAs), which have the highest optical depth (tau) in the tau distribution, and mass overdensities on the scales of similar to 10-20 h(-1) comoving Mpc. On such large scales, our cosmological simulations show a strong correlation between the effective optical depth (tau(eff)) of the CoSLAs and the three-dimensional mass overdensity. In spectra with moderate signal-to-noise ratio, however, the profiles of CoSLAs can be confused with individual high column density absorbers. For z > 2.6, where the corresponding Ly beta is redshifted to the optical, we have developed a selection technique to distinguish between these two alternatives. We have applied this technique to similar to 6000 sight lines provided by Sloan Digital Sky Survey III quasar survey at z = 2.6-3.3 with a continuum-to-noise ratio greater than 8, and we present a sample of five CoSLA candidates with tau(eff) on 15 h(-1) Mpc greater than 4.5x the mean optical depth. At lower redshifts of z < 2.6, where the background quasar density is higher, the overdensity can be traced by intergalactic absorption groups using multiple sight lines with small angular separations. Our overdensity searches fully use the current and next generation of Ly alpha forest surveys, which cover a survey volume of > 1 (h(-1) Gpc)(3). Systems traced by CoSLAs will yield a uniform sample of the most massive overdensities at z > 2 to provide stringent constraints to models of structure formation.


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