Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Prior-less derivation of the astrophysical factor of Dwarf Spheroidal galaxies
Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC). Stockholm University, Faculty of Science, Department of Physics.ORCID iD: 0000-0003-0586-7634
2017 (English)Licentiate thesis, monograph (Other academic)
Abstract [en]

Dwarf spheroidal satellite galaxies (dSphs) of the Milky Way are considered ideal targets for particle Dark Matter (DM) identification. Indirect detection strategies entail examining dSphs in search for signals of annihilating or decaying DM, in the form of excess electrons or gamma- and X-ray photons above the astrophysical background. To robustly compare model predictions with the observed fluxes of such product particles, most analyses of astrophysical data - which are generally frequentist - rely on estimating the abundance of DM by calculating the so-called J-factor. This quantity is usually inferred from the kinematic properties of the stellar population of a dSph using Jeans equation, commonly by means of Bayesian techniques. Previous works have, therefore, combined different statistical methods when analysing astrophysical data from dSphs. In this thesis, I describe the development of a new, fully-frequentist approach for constructing profile likelihood curves for the J-factor of dSphs. I then use kinematic data from 20 dSphs to derive estimates of their maximum likelihood J-factor and its confidence intervals. The obtained J-factors and their uncertainties are in good agreement with previous, Bayesian-derived values. This technique is validated using a publicly available simulation suite, released by Gaia Challenge, by evaluating its coverage and bias. The results of these tests indicate that the method possess good statistical properties. The implications of these findings for DM searches are discussed, together with future improvements and extensions of this technique.

Place, publisher, year, edition, pages
Stockholm University, 2017.
Keywords [en]
dwarf galaxies; dark matter
National Category
Astronomy, Astrophysics and Cosmology
Research subject
Physics
Identifiers
URN: urn:nbn:se:su:diva-148183OAI: oai:DiVA.org:su-148183DiVA, id: diva2:1150025
Presentation
2017-11-09, 15:12 (English)
Opponent
Supervisors
Available from: 2018-02-16 Created: 2017-10-17 Last updated: 2018-02-16Bibliographically approved

Open Access in DiVA

No full text in DiVA

Search in DiVA

By author/editor
chiappo, andrea
By organisation
The Oskar Klein Centre for Cosmo Particle Physics (OKC)Department of Physics
Astronomy, Astrophysics and Cosmology

Search outside of DiVA

GoogleGoogle Scholar

urn-nbn

Altmetric score

urn-nbn
Total: 4 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf