English
Related papers

Related papers: Modeling assembly bias with machine learning and s…

200 papers

Stellar and AGN-driven feedback processes affect the distribution of gas on a wide range of scales, from within galaxies well into the intergalactic medium. Yet, it remains unclear how feedback, through its connection to key galaxy…

Astrophysics of Galaxies · Physics 2025-12-15 Daniele Sorini , Sownak Bose , Mathilda Denison , Romeel Davé

We present a set of mock redshift catalogs, constructed from N-body simulations, designed to mimic the DEEP2 survey. Galaxies with a range of luminosities are placed within virialized halos in the simulation using a variant of the halo…

Astrophysics · Physics 2008-11-26 Renbin Yan , Martin White , Alison L. Coil

Hierarchical structure formation implies that the number of subhalos within a dark matter halo depends not only on halo mass, but also on the formation history of the halo. This dependence on the formation history, which is highly…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-27 Yao-Yuan Mao , Marc Williamson , Risa H. Wechsler

Semi-analytic models (SAMs) systematically predict higher stellar-mass scatter at a given halo mass than hydrodynamical simulations and most empirical models. Our goal is to investigate the physical origin of this scatter by exploring…

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

Secondary halo bias, commonly known as 'assembly bias,' is the dependence of halo clustering on a halo property other than mass. This prediction of the Lambda-Cold Dark Matter cosmology is essential to modelling the galaxy distribution to…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-30 Yao-Yuan Mao , Andrew R. Zentner , Risa H. Wechsler

We present new analytical estimates of the large scale bias of neutral hydrogen (HI). We use a simple, non-parametric model which monotonically relates the total mass of a halo M_tot with its HI mass M_HI at zero redshift; for earlier times…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Felipe Marin , Nickolay Y. Gnedin , Hee-Jong Seo , Alberto Vallinotto

Assembly bias, which is the variation in halo clustering at fixed mass driven by formation history, has long been predicted by numerical simulations but remains difficult to confirm observationally. Previous studies have reported evidence…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-14 Zhenjie Liu , Hironao Miyatake , Joop Schaye , Matthieu Schaller , Keitaro Ishikawa , Tomomi Sunayama

Motivated by previous findings that the magnitude gap between certain satellite galaxy and the central galaxy can be used to improve the estimation of halo mass, we carry out a systematic study of the information content of different member…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-30 Yanrui Zhou , Jiaxin Han

The halo occupation distribution (HOD) approach has proven to be an effective method for modeling galaxy clustering and bias. In this approach, galaxies of a given type are probabilistically assigned to individual halos in N-body…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-15 Juliana Kwan , Katrin Heitmann , Salman Habib , Nikhil Padmanabhan , Hal Finkel , Nick Frontiere , Adrian Pope

Cosmological galaxy formation simulations are still limited by their spatial/mass resolution and cannot model from first principles some of the processes, like star formation, that are key in driving galaxy evolution. As a consequence they…

Astrophysics of Galaxies · Physics 2022-03-02 Andrea V. Macciò , Mohamad Ali-Dib , Pavle Vulanović , Hind Al Noori , Fabian Walter , Nico Krieger , Tobias Buck

We address the question of whether or not assembly bias arises in the absence of highly non-linear effects such as tidal stripping of halos near larger mass concentrations. Therefore, we use a simplified dynamical scheme where these effects…

Astrophysics · Physics 2009-11-13 Jose Ariel Keselman , Adi Nusser

Baryonic physics is anticipated to be a major source of systematic uncertainty in current and future large-scale cosmological surveys. We investigate how baryonic effects on halo density profiles vary with secondary halo properties at fixed…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-01 Yikun Wang , Idit Zehavi , Sergio Contreras , Giovanni Aricò , Sownak Bose , Lars Hernquist

The simplest scheme for predicting real galaxy properties after performing a dark matter simulation is to rank order the real systems by stellar mass and the simulated systems by halo mass and then simply assume monotonicity - that the more…

Astrophysics of Galaxies · Physics 2021-10-22 Stephanie Tonnesen , Jeremiah P. Ostriker

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

We use machine learning to classify galaxies according to their HI content, based on both their optical photometry and environmental properties. The data used for our analyses are the outputs in the range $z = 0-1$ from MUFASA cosmological…

Astrophysics of Galaxies · Physics 2020-02-05 Sambatra Andrianomena , Mika Rafieferantsoa , Romeel Davé

[Abridged] We study the abundance and clustering properties of HI at redshifts $z\leqslant5$ using TNG100, a large state-of-the-art magneto-hydrodynamic simulation of a 75 Mpc/h box size. We show that most of the HI lies within dark matter…

We study potential systematic effects of assembly bias on cosmological parameter constraints from redshift space distortion measurements. We use a semi-analytic galaxy formation model applied to the Millennium N-body WMAP-7 simulation to…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-27 Nelson Padilla , Sergio Contreras , Idit Zehavi , Carlton Baugh , Peder Norberg

The analysis of state-of-the-art cosmological surveys like the Dark Energy Spectroscopic Instrument (DESI) survey requires high-resolution, large-volume simulations. However, the computational cost of hydrodynamical simulations at these…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-19 M. Icaza-Lizaola , E. L. Sirks , Yong-Seon Song , Peder Norberg , Feng Shi

Intensity mapping surveys will provide access to a coarse view of the cosmic large-scale structure in unprecedented large volumes at high redshifts. Given the large fractions of the sky that can be efficiently scanned using emission from…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-09 Oliver Leicht , Cora Uhlemann , Francisco Villaescusa-Navarro , Sandrine Codis , Lars Hernquist , Shy Genel