English
Related papers

Related papers: The Delayed Formation of Dwarf Galaxies

200 papers

According to the now strongly supported concordance $\Lambda$CDM model, galaxies may be grossly described as a luminous component embedded in a dark matter halo. The density profile of these mass dominating haloes may be determined by N -…

Cosmology and Nongalactic Astrophysics · Physics 2014-02-04 A. Del Popolo , V. F. Cardone

The first generation of stars produces a background of Lyman-Werner (LW) radiation which can photo-dissociate molecular hydrogen, increasing the mass of dark matter halos required to host star formation. Previous studies have determined the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Eli Visbal , Zoltan Haiman , Bryan Terrazas , Greg L. Bryan , Rennan Barkana

Dwarf galaxies serve as key models for understanding galaxy assembly in the early universe, with their final properties influenced by environmental factors. Using the dark matter-only simulation "Copernicus Complexio" (COCO) and the…

Recent JWST observations suggest an excess of $z\gtrsim10$ galaxy candidates above most theoretical models. Here, we explore how the interplay between halo formation timescales, star formation efficiency and dust attenuation affects the…

Astrophysics of Galaxies · Physics 2023-01-12 Charlotte A. Mason , Michele Trenti , Tommaso Treu

We present new cooling sequences, color-magnitude diagrams, and color-color diagrams for cool white dwarfs with pure hydrogen atmospheres down to an effective temperature $\te=1500$ K. We include a more detailed treatment of the physics of…

Astrophysics · Physics 2009-10-31 Gilles Chabrier , Pierre Brassard , Gilles Fontaine , Didier Saumon

The properties of gas in the halos of galaxies constrain global models of the interstellar medium. Kinematical information is of particular interest since it is a clue to the origin of the gas. Until now mostly massive galaxies have been…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 P. Kamphuis , R. F. Peletier , P. C. van der Kruit , G. H. Heald

We present an analysis of the neutral hydrogen (HI) properties of a fully cosmological hydrodynamical dwarf galaxy, run with varying simulation parameters. As reported by Governato et al. (2010), the high resolution, high star formation…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 K. Pilkington , B. K. Gibson , F. Calura , A. M. Brooks , L. Mayer , C. B. Brook , G. S. Stinson , R. J. Thacker , C. G. Few , D. Cunnama , J. Wadsley

We explore mechanisms for the regulation of star formation in dwarf galaxies. We concentrate primarily on a sample in the Virgo cluster, which has HI and blue total photometry, for which we collected H$\alpha$ data at the Wise Observatory.…

Astrophysics · Physics 2009-10-30 Noah Brosch , Ana Heller , Elchanan Almoznino

We study the impact of molecular (${\rm H_2}$) and atomic (HI) hydrogen cooling on the galaxy formation threshold. We calculate the fraction of dark matter (DM) halos that exceeds a critical mass required for star formation,…

Astrophysics of Galaxies · Physics 2025-04-09 Ethan O. Nadler

We present a framework for high-redshift ($z \geq 7$) galaxy formation that traces their dark matter (DM) and baryonic assembly in four cosmologies: Cold Dark Matter (CDM) and Warm Dark Matter (WDM) with particle masses of $m_x =$ 1.5, 3…

Astrophysics of Galaxies · Physics 2015-06-17 Pratika Dayal , Andrei Mesinger , Fabio Pacucci

(Shortened) We use N-body simulations to investigate the structure and dynamical evolution of dark matter halos in galaxy clusters. Our sample consists of nine massive halos from an EdS universe with scale free power spectrum and n = -1.…

Astrophysics · Physics 2015-06-24 Giuseppe Tormen , Francois R. Bouchet , Simon D. M. White

Based upon a novel paradigm of the galaxy formation under UV background, the evolutionary bifurcation of pregalactic clouds is confronted with observations on elliptical and spiral galaxies. The theory predicts that the dichotomy between…

Astrophysics · Physics 2009-10-31 Hajime Susa , Masayuki Umemura

Very little work has been done on star formation in dwarf lenticular galaxies (S0s). We present 2D-spectroscopic and millimetre observations made by Centro Astronomico Hispano Aleman (CAHA) 3.5 m optical and the IRAM-30 m millimetre…

Astrophysics of Galaxies · Physics 2021-09-22 Xue Ge , Qiu-Sheng Gu , Ruben Garcıa-Benito , Shi-Ying Lu , Cheng-Long Lei , Nan Ding

Our goal is to study the effects of the UV radiation from the first stars, quasars and hypothetical Super Heavy Dark Matter (SHDM) particle decays on the formation of primordial bound objects in the Universe. We trace the evolution of a…

Astrophysics · Physics 2015-06-24 Jaroslaw Stasielak , Slawomir Stachniewicz , Marek Kutschera

Early JWST observations have revealed substantial numbers of galaxies out to redshifts as high as $z \simeq 14$, reflecting a slow evolution of the galaxy UV luminosity function (LF) not anticipated by many models of galaxy evolution. The…

Astrophysics of Galaxies · Physics 2025-04-16 C. T. Donnan , J. S. Dunlop , R. J. McLure , D. J. McLeod , F. Cullen

We use analytical and $N$-body methods to study the evolution of dwarf spheroidal galaxies (dSphs) embedded in dark matter (DM) haloes that host a sizeable subhalo population. Dark subhaloes generate a fluctuating gravitational field that…

Astrophysics of Galaxies · Physics 2025-10-22 Jorge Peñarrubia , Raphaël Errani , Eduardo Vitral , Matthew G. Walker

We have carried out a deep infrared imaging survey (1.1um and 1.6um) of the Hubble Deep Field North (HDF-N) using NICMOS on board the Hubble Space Telescope. The combined WFPC2+NICMOS data set lets us study galaxy morphologies, colors and…

Astrophysics · Physics 2007-05-23 Mark Dickinson

We estimate the cosmic number density of the recently identified class of HI-bearing ultra-diffuse sources (HUDs) based on the completeness limits of the ALFALFA survey. These objects fall in the range $8.5 < \log M_{\rm{HI}}/\rm{M_{\odot}}…

A subset of blazars emit TeV gamma rays which annihilate and pair produce on the extragalactic background light. We have argued in Broderick et al. (2011, Paper I) that plasma beam instabilities can dissipate the pairs' energy locally. This…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Christoph Pfrommer , Philip Chang , Avery E. Broderick

Even though the dark-matter power spectrum in the absence of biasing predicts a number density of halos n(M) ~ M^-2 (i.e. a Schechter alpha value of -2) at the low-mass end (M < 10^10 M_solar), hydrodynamic simulations have typically…

Astrophysics of Galaxies · Physics 2015-05-20 D. C. Hambrick , J. P. Ostriker , P. H. Johansson , T. Naab
‹ Prev 1 4 5 6 7 8 10 Next ›