Browsing Institutt for teoretisk astrofysikk by Title
Now showing items 56-75 of 1279
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(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)Abstract How filaments form and erupt are topics about which solar researchers have wondered for more than a century and they are still open to debate. We present observations of a filament formation, its failed eruption, ...
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(Master thesis / Masteroppgave, 2016)
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(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2023)The gravitational lens system PS J0147+4630 (Andromeda’s Parachute) consists of four quasar images ABCD and a lensing galaxy. We obtained r -band light curves of ABCD in the 2017−2022 period from monitoring with two 2 m ...
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(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2020)
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(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2023)We present Atacama Large Millimetre/submillimetre Array (ALMA) CO(1–0) observations of the nearby infrared luminous (LIRG) galaxy pair IRAS 05054+1718 (also known as CGCG 468-002), as well as a new analysis of X-ray data ...
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(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2016)Solar spicules are chromospheric fibrils that appear everywhere on the Sun, yet their origin is not understood. Using high resolution observations of spicules obtained with the Swedish 1 m Solar Telescope, we aim to ...
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(Doctoral thesis / Doktoravhandling, 2014)
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(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2015)The Gaussian kinematic formula (GKF) [R. J. Adler and J. E. Taylor, Random Fields and Geometry (Springer, New York, 2007).] is an extremely powerful tool allowing for explicit analytic predictions of expected values of ...
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(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2023)We present asevolution, a cosmological N-body code developed based on gevolution, which consistently solves for the (a)symmetron scalar field and metric potentials within the weak-field approximation. In asevolution, the ...
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(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)ABSTRACT Quantifying tensions – inconsistencies amongst measurements of cosmological parameters by different experiments – has emerged as a crucial part of modern cosmological data analysis. Statistically significant ...
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(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2015)We present unpublished observations of Comet Donati 1858 V recently recovered in an old storage facility at the University Observatory in Oslo. Carefully-made drawings reveal temporal changes in the appearance of this ...
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(Master thesis / Masteroppgave, 2011)The existence of dark matter is a well established fact both due to galaxy rotation curves and also due to the CMB temperature anisotropies and the matter power spectra. According to the $\Lambda$CDM model, the so called ...
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(Master thesis / Masteroppgave, 2022)This thesis aims to revive the data gathered by the Diffuse Infrared Background Experiment (DIRBE) aboard the COsmic Background Explorer (COBE ) satellite, and, through modernizing this dataset, make it available for future ...
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(Doctoral thesis / Doktoravhandling, 2019)Einstein's theory of general relativity is currently our best model for how gravity works. It can be used to predict motions of planets, the speed-up of clocks on GPS satellites, and gravitational waves. General relativity ...
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(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2023)The Laser Interferometer Space Antenna (LISA) will be a transformative experiment for gravitational wave astronomy, and, as such, it will offer unique opportunities to address many key astrophysical questions in a completely ...
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(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2024)Observations of the millimeter sky contain valuable information on a number of signals, including the blackbody cosmic microwave background (CMB), Galactic emissions, and the Compton-y distortion due to the thermal ...
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(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)The 2014 March 29 X1 solar flare (SOL20140329T17:48) produced bright continuum emission in the far- and near-ultraviolet (NUV) and highly asymmetric chromospheric emission lines, providing long-sought constraints on the ...
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(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)Active region moss—the upper transition region of hot loops—was observed exhibiting rapid intensity variability on timescales of order 15 s by Testa et al. in a short time series (~150 s) data set from Hi-C (High-resolution ...
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(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)Ellerman bombs are transient brightenings in the wings of Hα 6563 Å that pinpoint photospheric sites of magnetic reconnection in solar active regions. Their partial visibility in the 1600 Å and 1700 Å continua registered ...
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(Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)ABSTRACT Many astrophysical and terrestrial scenarios involving magnetic fields can be approached in axial geometry. Although the smoothed particle hydrodynamics (SPH) technique has been successfully extended to ...