Search Results - "Xavier Prochaska, J"

A cold, massive, rotating disk galaxy 1.5 billion years after the Big Bang by Neeleman, Marcel, Prochaska, J. Xavier, Kanekar, Nissim, Rafelski, Marc

“…Massive disk galaxies like the Milky Way are expected to form at late times in traditional models of galaxy formation 1 , 2 , but recent numerical simulations…”
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The PHLEK Survey: A New Determination of the Primordial Helium Abundance by Hsyu, Tiffany, Cooke, Ryan J., Prochaska, J. Xavier, Bolte, Michael

“…We present Keck NIRSPEC and Keck NIRES spectroscopy of sixteen metal-poor galaxies that have pre-existing optical observations. The near-infrared (NIR)…”
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Correcting C iv-based virial black hole masses by Coatman, Liam, Hewett, Paul C, Banerji, Manda, Richards, Gordon T, Hennawi, Joseph F, Prochaska, J Xavier

“…The C IV...1498,1501 broad emission line is visible in optical spectra to redshifts exceeding z ~ 5. C IV has long been known to exhibit significant…”
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The physical properties of z > 2 Lyman limit systems: new constraints for feedback and accretion models by Fumagalli, Michele, O'Meara, John M, Prochaska, J Xavier

“…We study the physical properties of a homogeneous sample of 157 optically thick absorption line systems at redshifts ~1.8-4.4, selected from a high-dispersion…”
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A semisupervised machine learning search for never-seen gravitational-wave sources by Marianer, Tom, Poznanski, Dovi, Prochaska, J Xavier

“…ABSTRACT By now, tens of gravitational-wave (GW) events have been detected by the LIGO and Virgo detectors. These GWs have all been emitted by compact binary…”
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EARLY AND EXTENDED HELIUM REIONIZATION OVER MORE THAN 600 MILLION YEARS OF COSMIC TIME by Worseck, Gabor, Prochaska, J Xavier, Hennawi, Joseph F, McQuinn, Matthew

“…We measure the effective optical depth of He ii Ly α absorption at in 17 UV-transmitting quasars observed with UV spectrographs on the Hubble Space Telescope …”
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Detection of Pristine Gas Two Billion Years After the Big Bang by Fumagalli, Michele, O'Meara, John M., Prochaska, J. Xavier

“…In the current cosmological model, only the three lightest elements were created in the first few minutes after the Big Bang; all other elements were produced…”
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Characterizing the Fast Radio Burst Host Galaxy Population and its Connection to Transients in the Local and Extragalactic Universe by Bhandari, Shivani, Heintz, Kasper E., Aggarwal, Kshitij, Marnoch, Lachlan, Day, Cherie K., Sydnor, Jessica, Burke-Spolaor, Sarah, Law, Casey J., Xavier Prochaska, J., Tejos, Nicolas, Bannister, Keith W., Butler, Bryan J., Deller, Adam T., Ekers, R. D., Flynn, Chris, Fong, Wen-fai, James, Clancy W., Lazio, T. Joseph W., Luo, Rui, Mahony, Elizabeth K., Ryder, Stuart D., Sadler, Elaine M., Shannon, Ryan M., Han, JinLin, Lee, Kejia, Zhang, Bing

“…We present the localization and host galaxies of one repeating and two apparently nonrepeating fast radio bursts (FRBs). FRB 20180301A was detected and…”
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Multiphase outflows in post-starburst E+A galaxies - II. A direct connection between the neutral and ionized outflow phases by Baron, Dalya, Netzer, Hagai, Davies, Ric I, Xavier Prochaska, J

“…ABSTRACT Post-starburst E+A galaxies are systems that hosted a powerful starburst that was quenched abruptly. Simulations suggest that these systems provide…”
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Quasar quartet embedded in giant nebula reveals rare massive structure in distant universe by Hennawi, Joseph F., Prochaska, J. Xavier, Cantalupo, Sebastiano, Arrigoni-Battaia, Fabrizio

“…All galaxies once passed through a hyperluminous quasar phase powered by accretion onto a supermassive black hole. But because these episodes are brief,…”
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MUSE Analysis of Gas around Galaxies (MAGG) – II: metal-enriched halo gas around z ∼ 1 galaxies by Dutta, Rajeshwari, Fumagalli, Michele, Fossati, Matteo, Lofthouse, Emma K, Prochaska, J Xavier, Arrigoni Battaia, Fabrizio, Bielby, Richard M, Cantalupo, Sebastiano, Cooke, Ryan J, Murphy, Michael T, O’Meara, John M

“…ABSTRACT We present a study of the metal-enriched cool halo gas traced by Mg ii absorption around 228 galaxies at z ∼ 0.8–1.5 within 28 quasar fields from the…”
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A UNIVERSAL DENSITY STRUCTURE FOR CIRCUMGALACTIC GAS by Stern, Jonathan, Hennawi, Joseph F., Prochaska, J. Xavier, Werk, Jessica K.

“…ABSTRACT We develop a new method to constrain the physical conditions in the cool (∼104 K) circumgalactic medium (CGM) from measurements of ionic column…”
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The low density and magnetization of a massive galaxy halo exposed by a fast radio burst by Prochaska, J Xavier, Macquart, Jean-Pierre, McQuinn, Matthew, Simha, Sunil, Shannon, Ryan M, Day, Cherie K, Marnoch, Lachlan, Ryder, Stuart, Deller, Adam, Bannister, Keith W, Bhandari, Shivani, Bordoloi, Rongmon, Bunton, John, Cho, Hyerin, Flynn, Chris, Mahony, Elizabeth K, Phillips, Chris, Qiu, Hao, Tejos, Nicolas

“…Present-day galaxies are surrounded by cool and enriched halo gas extending for hundreds of kiloparsecs. This halo gas is thought to be the dominant reservoir…”
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High time resolution and polarization properties of ASKAP-localized fast radio bursts by Day, Cherie K, Deller, Adam T, Shannon, Ryan M, Qiu(邱昊), Hao, Bannister, Keith W, Bhandari, Shivani, Ekers, Ron, Flynn, Chris, James, Clancy W, Macquart, Jean-Pierre, Mahony, Elizabeth K, Phillips, Chris J, Xavier Prochaska, J

“…ABSTRACT Combining high time and frequency resolution full-polarization spectra of fast radio bursts (FRBs) with knowledge of their host galaxy properties…”
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THE COS-HALOS SURVEY: ORIGINS OF THE HIGHLY IONIZED CIRCUMGALACTIC MEDIUM OF STAR-FORMING GALAXIES by Werk, Jessica K., Prochaska, J. Xavier, Cantalupo, Sebastiano, Fox, Andrew J., Oppenheimer, Benjamin, Tumlinson, Jason, Tripp, Todd M., Lehner, Nicolas, McQuinn, Matthew

“…ABSTRACT The total contribution of diffuse halo gas to the galaxy baryon budget strongly depends on its dominant ionization state. In this paper, we address…”
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The COS-Halos Survey: Metallicities in the Low-redshift Circumgalactic Medium by Prochaska, J. Xavier, Werk, Jessica K., Worseck, Gábor, Tripp, Todd M., Tumlinson, Jason, Burchett, Joseph N., Fox, Andrew J., Fumagalli, Michele, Lehner, Nicolas, Peeples, Molly S., Tejos, Nicolas

“…We analyze new far-ultraviolet spectra of 13 quasars from the COS-Halos survey that cover the H i Lyman limit of 14 circumgalactic medium (CGM) systems. These…”
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Implications of z ∼ 6 Quasar Proximity Zones for the Epoch of Reionization and Quasar Lifetimes by Eilers, Anna-Christina, Davies, Frederick B., Hennawi, Joseph F., Prochaska, J. Xavier, Luki, Zarija, Mazzucchelli, Chiara

“…We study quasar proximity zones in the redshift range 5.77 ≤ z ≤ 6.54 by homogeneously analyzing 34 medium-resolution spectra, encompassing both archival and…”
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Simple Models of Metal-line Absorption and Emission from Cool Gas Outflows by Prochaska, J. Xavier, Kasen, Daniel, Rubin, Kate

“…We analyze the absorption and emission-line profiles produced by a set of simple, cool gas wind models motivated by galactic-scale outflow observations. We…”
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QUASARS PROBING QUASARS. IV. JOINT CONSTRAINTS ON THE CIRCUMGALACTIC MEDIUM FROM ABSORPTION AND EMISSION by Hennawi, Joseph F, Prochaska, J Xavier

“…We have constructed a sample of 29 close projected quasar pairs where the background quasar spectrum reveals absorption from optically thick Hi gas associated…”
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THE H i CONTENT OF THE UNIVERSE OVER THE PAST 10 GYR by Neeleman, Marcel, Prochaska, J. Xavier, Ribaudo, Joseph, Lehner, Nicolas, Howk, J. Christopher, Rafelski, Marc, Kanekar, Nissim

“…ABSTRACT We use the Hubble Space Telescope (HST) archive of ultraviolet (UV) quasar spectroscopy to conduct the first blind survey for damped Ly absorbers…”
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