Now showing items 201-220 of 518

• (Master thesis / Masteroppgave, 2016)
If dark matter, after it has become non-relativistic, scatters elastically with a relativistic heat bath particle, then the resulting pressure leads to acoustic oscillations that suppress the growth of overdensities in the ...
• (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)
• (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)
SDSS J2222+2745 is a galaxy cluster at z = 0.49, strongly lensing a quasar at z = 2.805 into six widely separated images. In recent Hubble Space Telescope imaging of the field, we identify additional multiply lensed galaxies ...
• (Master thesis / Masteroppgave, 2015)
In 2013 a new metric called TARDIS was introduced. This metric was published by Tippet and Tsang, and described a time machine. This thesis uses numerical methods to explore properties of this new metric. We start by ...
• (Master thesis / Masteroppgave, 2019)
• (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)
We present detailed characteristics of linear polarization features (LPFs) in the quiet-Sun photosphere from high-resolution observations obtained with SUNRISE/IMaX. We explore differently treated data with various noise ...
• (Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)
We consider two stable Interacting Dark Matter-Dark Energy models and confront them against current Cosmic Microwave Background data from the Planck satellite. We then generate luminosity distance measurements from Script ...
• (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2014)
Cosmological local observables are at best statistically determined by the fundamental theory describing inflation. When the scalar inflaton is coupled uniformly to a collection of subdominant massless gauge vectors, ...
• (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)
With a total integration time of 168 h and a narrowband filter tuned to Lyα emission from z = 8.8, the UltraVISTA survey has set out to find some of the most distant galaxies, on the verge of the epoch of reionization. ...
• (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)
Direct collapse black holes forming in pristine, atomically cooling haloes at z ≈ 10–20 may act as the seeds of supermassive black holes (BHs) at high redshifts. In order to create a massive BH seed, the host halo needs ...
• (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)
• (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)
• (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2016)
The escape of ionizing Lyman continuum (LyC) photons requires the existence of low-NH I sightlines, which also promote escape of Lyα. We use a suite of 2500 Lyα Monte-Carlo radiative transfer simulations through models of ...
• (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)
We introduce Project MegaSaura: the Magellan Evolution of Galaxies Spectroscopic and Ultraviolet Reference Atlas. MegaSaura comprises medium-resolution, rest-frame ultraviolet spectroscopy of N = 15 bright gravitationally ...
• (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)
We stack the rest-frame ultraviolet spectra of N = 14 highly magnified gravitationally lensed galaxies at redshifts $1.6\lt z\lt 3.6$. The resulting new composite spans $900\lt {\lambda }_{\mathrm{rest}}\lt 3000$ Å, with ...
• (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)
Context: Umbral flashes (UF) and running penumbral waves (RPWs) in sunspot chromospheres leave a dramatic imprint in the intensity profile of the Ca II 8542 Å line. Recent studies have focussed on also explaining the ...
• (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2015)
Analytical models are presented for currents along vertical magnetic field lines due to slow bulk electron motion in plasmas subject to a gravitational force. It is demonstrated that a general feature of this problem is a ...
• (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2015)
Rapid magnetic up fl ows in the quiet-Sun photosphere were recently uncovered from both SUNRISE / IMaX and Hinode / SOT observations. Here, we study magnetic up flow events ( MUEs ) from high-quality, high- ( spatial, ...
• (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)