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Related papers: Ingredients for 21cm intensity mapping

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We investigate the signatures left by massive neutrinos on the spatial distribution of neutral hydrogen (HI) in the post-reionization era by running hydrodynamic simulations that include massive neutrinos as additional collisionless…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-09 Francisco Villaescusa-Navarro , Philip Bull , Matteo Viel

We investigate the spatial clustering of dark matter halos, collapsing from $1-4 \sigma$ fluctuations, in the redshift range $0 - 5$ using N-body simulations. The halo bias of high redshift halos ($z \geq 2$) is found to be strongly…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-19 Charles Jose , Cedric G. Lacey , Carlton M. Baugh

This is the third paper in a series in which we attempt to put constraints on the flattening of dark halos in disk galaxies. For this purpose we need to analyse the observed XV diagrams in edge-on galaxies to accurately measure the radial…

Astrophysics of Galaxies · Physics 2015-05-18 J. C. O'Brien , K. C. Freeman , P. C. van der Kruit

We identify 814 discrete HI clouds in 40 dwarf irregular galaxies from the LITTLE THINGS survey using an automated cloud-finding algorithm. The cloud masses range from ~10^3 to 10^7 Msolar, have a surface density averaged over all of the…

Astrophysics of Galaxies · Physics 2019-06-05 Deidre A. Hunter , Bruce G. Elmegreen , Clara L. Berger

A cosmological zoom-in simulation which develops into a Milky Way-like halo is started at redshift 7. The initial dark matter distribution is seeded with dense star clusters, median mass $5\times 10^5 M_\sun$, placed in the largest…

Astrophysics of Galaxies · Physics 2022-01-19 Raymond G. Carlberg , Laura C. Keating

Neutral hydrogen (HI) will soon be the dark matter tracer observed over the largest volumes of Universe thanks to the 21 cm intensity mapping technique. To unveil cosmological information it is indispensable to understand the HI…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-06 Aurélie Pénin , Obinna Umeh , Mario Santos

We use cosmological hydrodynamic simulations with stellar feedback from the FIRE project to study the physical nature of Lyman limit systems (LLSs) at z<1. At these low redshifts, LLSs are closely associated with dense gas structures…

Astrophysics of Galaxies · Physics 2017-06-21 Z. Hafen , C. -A. Faucher-Giguere , D. Angles-Alcazar , D. Keres , R. Feldmann , T. K. Chan , E. Quataert , N. Murray , P. F. Hopkins

New 21cm observations with the Green Bank Telescope show that a significant fraction of the HI in the inner Galaxy's halo 1 kpc from the midplane exists in the form of discrete clouds. Some look very much like a Spitzer ``standard'' diffuse…

Astrophysics · Physics 2007-05-23 Felix J. Lockman

Aims: we studied the global distribution and kinematics of the extra-planar neutral gas in the Milky Way. Methods: we built 3D models for a series of Galactic HI layers, projected them for an inside view, and compared them with the…

Astrophysics of Galaxies · Physics 2015-05-20 Antonino Marasco , Filippo Fraternali

We present a study on the clustering of a stellar mass selected sample of 18,482 galaxies with stellar masses M*>10^10M(sun) at redshifts 0.4<z<2.0, taken from the Palomar Observatory Wide-field Infrared Survey. We examine the clustering…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-15 S. Foucaud , C. J. Conselice , W. G. Hartley , K. P. Lane , S. P. Bamford , O. Almaini , K. Bundy

We analyze high resolution, N-body hydrodynamical simulations of fiducial galaxy clusters to probe tidal stripping of the dark matter subhalos. These simulations include a prescription for star formation allowing us to track the fate of the…

We detect the neutral hydrogen (HI) radial brightness temperature profile in large-scale haloes by stacking 48,430 galaxies selected from the 2dFGRS catalogue onto a set of 21-cm intensity maps obtained with the Parkes radio telescope,…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-14 Denis Tramonte , Yin-Zhe Ma

The neutral atomic gas content of individual galaxies at large cosmological distances has until recently been difficult to measure due to the weakness of the hyperfine HI 21-cm transition. Here we estimate the HI gas mass of a sample of…

Observations of the cold neutral atomic hydrogen (HI) in and around disc galaxies have revealed that spatial and kinematic asymmetries are commonplace, and are reflected in the global HI spectra. We use the TNG100 box from the IllustrisTNG…

Astrophysics of Galaxies · Physics 2020-10-21 Adam B. Watts , Chris Power , Barbara Catinella , Luca Cortese , Adam R. H. Stevens

HI intensity mapping data traces the large-scale structure matter distribution using the integrated emission of neutral hydrogen gas (HI). The cross-correlation of the intensity maps with optical galaxy surveys can mitigate foreground and…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-28 L. Wolz , S. G. Murray , C. Blake , J. S. Wyithe

We use a combination of N-body simulations of the hierarchical clustering of dark matter and semi-analytic modelling of the physics of galaxy formation to probe the relationship between the galaxy distribution and the mass distribution. The…

Astrophysics · Physics 2009-10-31 A. J. Benson , C. M. Baugh , S. Cole , C. S. Frenk , C. G. Lacey

We use 666 blue horizontal branch (BHB) stars from the 2Qz redshift survey to map the Galactic halo in four dimensions (position, distance and velocity). We find that the halo extends to at least 100 kpc in Galactocentric distance, and…

Astrophysics of Galaxies · Physics 2015-05-19 Roberto De Propris , Craig D. Harrison , Peter J. Mares , CTIO , Cornell University

We have recently identified several high velocity (V < -100 km/s) clouds in the directions of Mrk 509 and PKS 2155-304 that have unusual ionization properties. The clouds exhibit strong C IV absorption with little or no detectable low ion…

Astrophysics · Physics 2009-10-30 Kenneth R. Sembach , Blair D. Savage , Limin Lu , Edward M. Murphy

We investigate the impact of neutral hydrogen (HI) in galaxies on the statistics of 21-cm fluctuations using analytic and semi-numerical modelling. Following the reionisation of hydrogen the HI content of the Universe is dominated by damped…

Astrophysics · Physics 2015-05-13 Stuart Wyithe , Lila Warszawski , Paul M. Geil , S. Peng Oh

We present dark-matter minihalo models for the Ultra-Compact High Velocity HI Clouds (UCHVCs) recently discovered in the 21 cm ALFALFA survey. We assume gravitational confinement of 10^4 K HI gas by flat-cored dark-matter subhalos within…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-06 Yakov Faerman , Amiel Sternberg , Christopher F. McKee
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