English
Related papers

Related papers: Sensitivity analysis of a galaxy formation model

200 papers

Next generation large scale surveys probe the nonlinear regime with high resolution. Making viable cosmological inferences based on these observations requires accurate theoretical modeling of the mildly nonlinear regime. In this work we…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-29 Sarah Safi , Marzieh Farhang

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

One-dimensional Poincare inequalities are used in Global Sensitivity Analysis (GSA) to provide derivative-based upper bounds and approximations of Sobol indices. We add new perspectives by investigating weighted Poincare inequalities. Our…

Probability · Mathematics 2024-12-09 David Heredia , Aldéric Joulin , Olivier Roustant

A wide array of graphical models can be parametrised to have atomic probabilities represented by monomial functions. Such monomial structure has proven very useful when studying robustness under the assumption of a multilinear model where…

Statistics Theory · Mathematics 2019-01-09 Manuele Leonelli

We compare global predictions from the EAGLE hydrodynamical simulation, and two semi-analytic (SA) models of galaxy formation, L-GALAXIES and GALFORM. All three models include the key physical processes for the formation and evolution of…

We report the discovery of a rare new form of long-term radio variability in the light-curves of active galaxies (AG) --- Symmetric Achromatic Variability (SAV) --- a pair of opposed and strongly skewed peaks in the radio flux density…

The high sensitivity of the new generation of radio telescopes such as the Square Kilometre Array (SKA) will allow cosmological weak lensing measurements at radio wavelengths that are competitive with optical surveys. We present an…

Instrumentation and Methods for Astrophysics · Physics 2016-09-23 Marzia Rivi , Lance Miller , Sphesihle Makhathini , Filipe Batoni Abdalla

We implement physically motivated recipes for partitioning cold gas into different phases (atomic, molecular, and ionized) in galaxies within semi-analytic models of galaxy formation based on cosmological merger trees. We then model the…

Astrophysics of Galaxies · Physics 2015-09-30 Rachel S. Somerville , Gergö Popping , Scott C. Trager

The standard Halo Occupation Distribution (HOD) models were originally developed based on results from semi-analytic and hydrodynamical galaxy formation models. Those models have since progressed, in particular to include AGN feedback to…

Astrophysics of Galaxies · Physics 2017-05-08 Nuala McCullagh , Peder Norberg , Shaun Cole , Violeta Gonzalez-Perez , Carlton Baugh , John Helly

The SKA will be a unique instrument with which to study the evolution of the gas content of galaxies. A proposed deep (~8 Msec) 'pencil-beam' survey is simulated using recently updated specifications for SKA sensitivity and survey speed.…

Astrophysics · Physics 2009-06-23 Lister Staveley-Smith

Many mathematical models involve input parameters, which are not precisely known. Global sensitivity analysis aims to identify the parameters whose uncertainty has the largest impact on the variability of a quantity of interest (output of…

Statistics Theory · Mathematics 2013-03-27 Alexandre Janon , Thierry Klein , Agnes Lagnoux-Renaudie , Maëlle Nodet , Clémentine Prieur

Variability is a property shared by virtually all active galactic nuclei (AGNs), and was adopted as a criterion for their selection using data from multi epoch surveys. Low Luminosity AGNs (LLAGNs) are contaminated by the light of their…

Astrophysics · Physics 2009-11-13 D. Trevese , K. Boutsia , F. Vagnetti , E. Cappellaro , S. Puccetti

This paper addresses some questions which have arisen from the use of the S\'ersic r^{1/n} law in modelling the luminosity profiles of early type galaxies. The first issue deals with the trend between the half-light radius and the…

Astrophysics · Physics 2009-11-06 Ignacio Trujillo , Alister W. Graham , Nicola Caon

Semi-analytic models are a widely used approach to simulate galaxy properties within a cosmological framework, relying on simplified yet physically motivated prescriptions. They have also proven to be an efficient alternative for generating…

Uncertainties exist in both physics-based and data-driven models. Variance-based sensitivity analysis characterizes how the variance of a model output is propagated from the model inputs. The Sobol index is one of the most widely used…

Methodology · Statistics 2020-06-09 Zhanlin Liu , Youngjun Choe

We use a semi-analytic model of galaxy formation to study signatures of large-scale modulations in the star formation (SF) activity in galaxies. In order to do this we carefully define local and global estimators of the density around…

Astrophysics · Physics 2015-05-13 R. E. Gonzalez , N. D. Padilla

We present results from the semi-analytic model of galaxy formation SAG applied on the MultiDark simulation MDPL2. SAG features an updated supernova (SN) feedback scheme and a robust modelling of the environmental effects on satellite…

Stochastic models are necessary for the realistic description of an increasing number of applications. The ability to identify influential parameters and variables is critical to a thorough analysis and understanding of the underlying…

Computation · Statistics 2016-11-29 Joseph L. Hart , Alen Alexanderian , Pierre A. Gremaud

We present a fast and accurate method to select an optimal set of parameters in semi-analytic models of galaxy formation and evolution (SAMs). Our approach compares the results of a model against a set of observables applying a stochastic…

Variance-based global sensitivity analysis (GSA) can provide a wealth of information when applied to complex models. A well-known Achilles' heel of this approach is its computational cost which often renders it unfeasible in practice. An…

Numerical Analysis · Mathematics 2026-01-08 John Darges , Alen Alexanderian , Pierre Gremaud
‹ Prev 1 4 5 6 7 8 10 Next ›