Essays about: "interstellar medium"

Showing result 6 - 10 of 12 essays containing the words interstellar medium.

  1. 6. Investigating Gas Turbulence in Galactic Discs

    University essay from Lunds universitet/Astronomi - Genomgår omorganisation

    Author : Timmy Ejdetjärn; [2019]
    Keywords : galaxies; gas; turbulence; interstellar medium; star formation; feedback; gravitational instability; local; high redshift; Physics and Astronomy;

    Abstract : The interstellar medium of both local and distant disc galaxies is observed to be supersonically turbulent and the turbulent motion of the gas is thought to be important for galaxy formation and evolution, particularly as a key ingredient for star formation. Consequently, this generates a striking relation between the star formation rate (SFR) and gas velocity dispersion ($\sigma_{\rm g}$; a measurement on the level of turbulence). READ MORE

  2. 7. The impact of turbulence on supernovae shockwaves

    University essay from Lunds universitet/Astronomi - Genomgår omorganisation

    Author : Loke Lönnblad Ohlin; [2018]
    Keywords : astrophysics; astronomy; supernovae; shockwaves; interstellar medium; massive stars; turbulence; molecular clouds; Physics and Astronomy;

    Abstract : The momentum and energy injection from supernovae is one of the main feedback modes, and is therefore key to the understanding of galaxy evolution and star formation. However, due to low resolution, large scale galaxy simulations often have issues with accurately modelling supernovae, and therefore rely on sub-grid models. READ MORE

  3. 8. Nucleosynthesis in accretion disks around black holes

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

    Author : Neige Frankel; [2017]
    Keywords : accretion disk; Nucleosynthesis; black hole; high energy; white dwarf tidal disruption; Physics and Astronomy;

    Abstract : Nucleosynthesis is the mechanism which produces new elements in nuclear reactions. Nuclear reaction rates are highly temperature dependant, and nuclear reactions take place in very hot environments. Current theories predict that the light elements such as hydrogen and helium were produced during the Big Bang. READ MORE

  4. 9. Forbidden oxygen in the Milky Way disk

    University essay from Lunds universitet/Astronomi - Genomgår omorganisation

    Author : Asma Sahli; [2017]
    Keywords : Physics and Astronomy;

    Abstract : Oxygen is produced inside massive stars and dispersed into the interstellar medium mainly through type II supernovae explosions. This element, which is the third most abundant one in the Universe, plays an important role in tracing the Galactic chemical history and evolution. READ MORE

  5. 10. Mapping the present-day chemical abundance structure of the Solar neighbourhood: O & Si

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

    Author : Kristiina Verro; [2017]
    Keywords : astrophysics; stellar spectroscopy; abundance analysis; solar neighbourhood; massive stars; Galaxy; Physics and Astronomy;

    Abstract : Context. Large scale chemical abundance gradients in the Galactic disks, small-scale abundance structures, and the mean chemical abundance values in the Solar vicinity, are important constraints to Galactic chemo-dynamical formation and evolution models. READ MORE