Essays about: "dark matter halos"

Showing result 1 - 5 of 8 essays containing the words dark matter halos.

  1. 1. Void Evolution and Cosmic Star Formation

    University essay from Uppsala universitet/Institutionen för fysik och astronomi

    Author : Joel Wasserman; [2023]
    Keywords : Void; Void Evolution; Cosmic Void; Star Formation Rate; Star Formation History; Cosmic Star Formation; Cosmology; Spherical Evolution Model; SvdW; Vdn; Excursion Set Theory; Excursion Set Formalism; Astrophysics; Astronomy; Cosmic Web; Matter Transfer; Tomrum; Tomrumsutveckling; Kosmiska Tomrum; Stjärnbildningshastighet; Stjärnbildningshistorik; Kosmisk stjärnbildning; Kosmologi; Sfärisk Evolutionsmodell; SvdW; Vdn; Exkursionsset teori; Exkursionsset Formalism; Astrofysik; Astronomi; Kosmiska Spindelnätet; Masstransport;

    Abstract : The rate at which stars have formed throughout the history of theuniverse is not constant, it started out slow, increased until around redshift ∼ 2 when it reversed and became slower again. The reason for this behaviour is still being investigated with various models and simulations usually based upon dark matter halos. READ MORE

  2. 2. Starbursts at Cosmic Dawn : Formation of Globular Clusters, Ultra-Faint Dwarfs, and Population III star clusters at z > 6

    University essay from Stockholms universitet/Institutionen för astronomi

    Author : Olof Nebrin; [2022]
    Keywords : Cosmology; Galaxy Formation; Globular Clusters; First Stars; Dark Matter; Cosmic Dawn; Reionization; Ultra-Faint Dwarfs;

    Abstract : In the standard model of cosmology (ΛCDM) the first stars, star clusters, and galaxies are expected to have formed in short bursts of star formation in low-mass dark matter halos at high redshifts (). Up to this point, attempts to predict the properties and abundances of these luminous objects have made use of numerically expensive cosmological simulations. READ MORE

  3. 3. The spatial distribution of dark matter in the Universe

    University essay from Lunds universitet/Astronomi - Genomgår omorganisation

    Author : Tamina Lund; [2020]
    Keywords : dark matter halos; NFW profile; curve fitting; Bayesian inference; least Squares; data uncertainties; Physics and Astronomy;

    Abstract : It was previously found that the density profile of dark matter halos is well-fit by a universal, smooth function over a vast range of masses and redshifts, named the Navarro-Frenk-White (NFW) profile after its discoverers. Despite its impressive goodness of fit, the NFW model remains an approximation of the density profile of realistic halos. READ MORE

  4. 4. An introduction to some ordinary differential equations governing stellar structures

    University essay from Lunds universitet/Matematik (naturvetenskapliga fakulteten)

    Author : Yani di Giovanni; [2019]
    Keywords : Mathematics and Statistics;

    Abstract : The Lane-Emden equation is a non-linear differential equation governing the equilibrium of polytropic stationary self-gravitating, spherically symmetric star models; $${\frac {1}{\xi ^{2}}}{\frac {d}{d\xi }}\left({\xi ^{2}{\frac {d\theta }{d\xi }}}\right)+\theta ^{n}=0.$$ In the isothermal cases we have the Chandrasekhar equation: $${\frac {1}{\xi ^{2}}}{\frac {d}{d\xi }}\left({\xi ^{2}{\frac {d\psi}{d\xi }}}\right)-e^{-\psi}=0$$ After having derived these models, we will go through all cases for which analytic solutions are achievable. READ MORE

  5. 5. Radial migration of stars, measured in N-body simulations

    University essay from Lunds universitet/Astronomi - Genomgår omorganisation; Lunds universitet/Institutionen för astronomi och teoretisk fysik - Genomgår omorganisation

    Author : Daniel Mikkola; [2017]
    Keywords : N-body; simulations; galaxies; radial migration; stars; Physics and Astronomy;

    Abstract : The purpose of Galactic archaeology is determining the history of the Milky Way (MW) Galaxy. To do this one uses observational data from stellar populations in terms of properties such as kinematics, chemistry, ages, and evolution. READ MORE