Sökning: "accretion rate"

Visar resultat 1 - 5 av 15 uppsatser innehållade orden accretion rate.

1. 1. Forming wide-orbit planets via pebble accretion

   Master-uppsats, Lunds universitet/Astrofysik; Lunds universitet/Fysiska institutionen

   Författare :Nerea Gurrutxaga; [2023]
   Nyckelord :Planet Formation; Pebble Accretion; Protoplanetary Disk; Wide-Orbit Planet; Physics and Astronomy;

   Sammanfattning : The possibility that detected substructures in protoplanetary disks, such as gaps, rings and cavities, are created by distant protoplanets has prompted an inquiry into the mechanism responsible for their formation. These wide-orbit young bodies are likely to form relatively rapidly in the outer regions of circumstellar disks. LÄS MER

3. 2. Colliding Galaxies in a (Nut)Shell

   Master-uppsats, Lunds universitet/Astronomi - Genomgår omorganisation; Lunds universitet/Fysiska institutionen

   Författare :Jonathan Petersson; [2022]
   Nyckelord :shell galaxies; simulations; starbursts; quenching; mergers; Physics and Astronomy;

   Sammanfattning : Galaxy interactions and mergers are natural recurring events in the current cosmological paradigm, events that often coincide with starbursts and enhanced star formation activity. To understand why that is, one can use idealised (non-cosmological) merger simulations, which provide freedom to recreate specific tidally distorted galaxies, and analysis of the time evolution and underlying physics of the star formation activity at a high spatial resolution. LÄS MER

4. 3. Lyman Continuum Radiation from Intermediate-Mass Black Holes : An Estimation of the Contribution of LyC Radiation from IMBHs in z~3 Galaxies

   Kandidat-uppsats, Uppsala universitet/Observationell astrofysik

   Författare :Marika Ljungberg; [2020]
   Nyckelord :intermediate-mass black holes; cosmic reionization; high-redshift galaxies;

   Sammanfattning : This thesis concerns the cosmic reionization of the intergalactic medium in the high redshift universe and, in particular, is a first approach to examine what role intermediate mass black holes (IMBHs) play in this cosmic age. Unexpectedly high values of hydrogen ionizing radiation, compared to current models, have been reported from galaxies at redshift ~3 (used as stand-ins for galaxies at the age of reionization), and thus these models need revision, potentially by adding effects of IMBH content in the galaxies. LÄS MER

5. 4. Analysis of Customer Behaviours on Customer Reviews and Ratings

   Magister-uppsats, KTH/Skolan för industriell teknik och management (ITM)

   Författare :Alkim Yetis; Erkut Kavak; [2020]
   Nyckelord :Customer reviews; e-commerce; customer behaviour; fashion industry; genderbased products; text-typed comments; content analysis; Kundrecensioner; e-handeln; kundbeteende; modebranschen; könsinriktade produkter; textskrivna kommentarer; innehållsanal;

   Sammanfattning : With the rapid accretion of online shopping, online customer reviews have become a very essential source. An interpretation of this essential source is not fulfilled with every aspect since online customer reviews consists of unstructured information. LÄS MER

7. 5. How did Jupiter form?

   Kandidat-uppsats, Lunds universitet/Astronomi - Genomgår omorganisation

   Författare :Calle Ahlgren; [2019]
   Nyckelord :Planet formation; Planet migration; Physics and Astronomy;

   Sammanfattning : Two relatively new concepts in planetary science are planetary migration; wherein the planets migrate through the protoplanetary disk as they form, and pebble accretion; wherein the planetesimals which become terrestrial planets and giant planet cores grow through the accretion of small pebbles. Planetary migration has become a generally accepted concept but there is still much to be learned even about how it affected the formation of our own solar system. LÄS MER