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Related papers: Molecular gas in high redshift QSOs

200 papers

We investigate the nature of CO emission from z~6 quasars by combining non-LTE radiative transfer calculations with merger-driven models of z~6 quasar formation that arise naturally in LCDM cosmological simulations. We consider four model…

(Abridged) We study the response of the gas to energetic processes associated with high-mass star formation and compare it with studies on low- and intermediate-mass young stellar objects (YSOs) using the same methods. The far-IR line…

The recent finding of substantial masses of cold molecular gas as well as young stellar populations in the host galaxies of quasars is at odds with results of Hubble Space Telescope imaging studies, since the latter appear to yield mature,…

Astrophysics · Physics 2009-11-11 P. D. Barthel

In recent years large efforts have been made to detect molecular gas towards high redshifted objects. Up to now the literature reports on only two cases of CO-detection in quasars at a redshift between 1 and 2 - Q0957+561, a gravitationally…

Astrophysics · Physics 2017-01-18 M. Krips , R. Neri , A. Eckart , J. Martin-Pintado , P. Planesas , L. Colina

Gas outflows are believed to play a pivotal role in shaping galaxies, as they regulate both star formation and black hole growth. Despite their ubiquitous presence, the origin and the acceleration mechanism of such powerful and extended…

Context: We investigated the molecular gas associated with 6.7 GHz methanol masers throughout the Galaxy using a J=1-0 transition of the CO isotopologues. Methods:Using the 13.7-meter telescope at the Purple Mountain Observatory (PMO), we…

Solar and Stellar Astrophysics · Physics 2014-09-05 Zhiyuan Ren , Yuefang Wu , Tie Liu , Lixin Li , Di Li , Binggang Ju

Using the Australia Telescope Compact Array (ATCA), we conducted a survey of CO J=1-0 and J=2-1 line emission towards strongly lensed high-redshift dusty star forming galaxies (DSFGs) previously discovered with the South Pole Telescope…

We investigate the redshift evolution of the molecular gas mass fraction (f_mol=M_mol/(M_star+M_mol), where M_mol is molecular gas mass and M_star is stellar mass) of galaxies in the redshift range of 0<z<2 as a function of the stellar mass…

Astrophysics of Galaxies · Physics 2015-10-28 Kana Morokuma-Matsui , Junichi Baba

We present new millimeter and radio observations of nine z~6 quasars discovered in deep optical and near-infrared surveys. We observed the 250 GHz continuum in eight of the nine objects and detected three of them. New 1.4 GHz radio…

Many massive galaxies at the centres of relaxed galaxy clusters and groups have vast reservoirs of cool (~10,000 K) and cold (~100 K) gas. In many low redshift brightest group and cluster galaxies this gas is lifted into the hot ISM in…

It becomes possible now to detect cold molecules at high redshift in the millimeter domain. Since the first discovery in 1992 by Brown and van den Bout of CO lines at z=2.28 in a gravitationally lensed starburst galaxy, nearly ten objects…

Astrophysics · Physics 2016-08-30 F. Combes

The relation between dark matter halos and the loci of star formation at high redshift is a pressing question in contemporary cosmology. Matching the abundance of halos to the abundance of infrared (IR) galaxies, we explicit the link…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-03 Matthieu Béthermin , Olivier Doré , Guilaine Lagache

The submillimeter CO lines are formed in warm and dense molecular gas and are therefore sensitive to the physical conditions whereas the CO (J=1-0) line is a tracer of the total molecular gas mass. In order to be able to compare the…

Astrophysics · Physics 2009-11-11 E. Bayet , M. Gerin , T. G. Phillips , A. Contursi

We present the detection of multiple CO line transitions with ALMA in a few tens of infrared-selected galaxies on and above the main sequence at z=1.1-1.7. We reliably detected the emission of CO(5-4), CO(2-1), and CO(7-6)+[CI](2-1) in 50,…

We test the use of long-wavelength dust continuum emission as a molecular gas tracer at high redshift, via a unique sample of 12, z~2 galaxies with observations of both the dust continuum and CO(1-0) line emission (obtained with the Atacama…

New HCN, HNC, and HCO+ measurements of 46 normal galaxies in transitions up to J=4-3 are included in a multitransition database covering HCN and HCO+ (130 galaxies) and HNC (94 galaxies). The near-linear luminosity relations are dominated…

Astrophysics of Galaxies · Physics 2023-03-08 F. P. Israel

Galactic-scale outflows of molecular gas from star-forming galaxies constitute the most direct evidence for regulation of star formation. In the early universe ($ z > 4 $), such outflows have recently been inferred from…

Astrophysics of Galaxies · Physics 2024-03-20 James Nianias , Jeremy Lim , Michael Yeung

Future observations with ALMA will be able to detect star-forming primordial gal axies, and perhaps even their dwarf spheroidal satellites, in CO emission lines at redshifts approaching 10. These observations will compliment other tools…

Astrophysics · Physics 2007-05-23 Nickolay Y. Gnedin , Joseph Silk , Marco Spaans

We report a sensitive search for the HCN(J=2-1) emission line towards SDSS J1148+5251 at z=6.42 with the VLA. HCN emission is a star formation indicator, tracing dense molecular hydrogen gas (n(H2) >= 10^4 cm^-3) within star-forming…

Astrophysics · Physics 2008-07-12 Dominik A. Riechers , Fabian Walter , Christopher L. Carilli , Frank Bertoldi

Most galaxy evolutionary models require quasar feedback to regulate star formation in their host galaxies. In particular, at high redshift, models expect that feedback associated with quasar-driven outflows is so efficient that the gas in…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 M. Cano-Diaz , R. Maiolino , A. Marconi , H. Netzer , O. Shemmer , G. Cresci