Now showing items 1-20 of 302

  • Tremblay, G. R.; Gladders, M. D.; Baum, S. A.; O'Dea, C. P.; Bayliss, M. B.; Cooke, K. C.; Dahle, Håkon; Davis, T. A.; Florian, M.; Rigby, J. R.; Sharon, K.; Soto, E; Wuyts, E (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2014)
    New Hubble Space Telescope ultraviolet and optical imaging of the strong-lensing galaxy cluster SDSS J1531+3414 (z = 0.335) reveals two centrally dominant elliptical galaxies participating in an ongoing major merger. The ...
  • Mendes Domingos Pereira, Tiago; Rouppe, Van Der Voort Luc; Carlsson, Mats (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 ...
  • Mikkelsen, Kristin (Doctoral thesis / Doktoravhandling, 2014)
  • Fantaye, Yabebal Tadesse; Marinucci, Domenico; Hansen, Frode Kristian; Maino, Davide (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 ...
  • Pettersen, Bjørn Ragnvald (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    We present unpublished observations of Comet Donati 1858 V recently recovered in an old storage facility at the University Observatory in Oslo.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 ...
  • Sivertsen, Sofie Vike (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 ...
  • Hoftuft, Jostein (Master thesis / Masteroppgave, 2009)
    The cosmic microwave background (CMB) radiation at 2.7 K is the leftover radiation from the Big Bang. By studying this radiation we can extract much information about the universe we live in. CMB experiments over the last ...
  • Sommer, Natalia Eiré (Master thesis / Masteroppgave, 2016)
  • Jimenez, Jose Beltran; Golovnev, A.; Karčiauskas, Mindaugas; Koivisto, Tomi Sebastian (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2012)
    The bimetric variational principle is a subtle reinterpretation of general relativity that assumes the spacetime connection to be generated by an independent metric. Unlike the so-called Palatini formalism that promotes ...
  • Rigby, J. R.; Bayliss, M. B.; Gladders, M. D.; Sharon, K.; Wuyts, E; Dahle, Håkon; Johnson, T.; Peña-Guerrero, M. (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2015)
    We measure [C iii] 1907, C iii] 1909 Å emission lines in 11 gravitationally lensed star-forming galaxies at z ~ 1.6–3, finding much lower equivalent widths than previously reported for fainter lensed galaxies. While it is ...
  • Leenaarts, Jorrit; Golding, Thomas Peter; Carlsson, Mats; Libbrecht, Tine; Joshi, Jayant (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2016)
    Context. The He i 1083 nm is a powerful diagnostic for inferring properties of the upper solar chromosphere, in particular for the magnetic field. The basic formation of the line in one-dimensional models is well understood, ...
  • Ninive, Per Harald (Master thesis / Masteroppgave, 2009)
    En mulig forklaring på at universet gikk inn i en fase av akselerert ekspansjon for 5-6 milliarder år siden, er at energitettheten i universet inneholder et bidrag fra et dynamisk skalarfelt. Problemet med denne forklaringen ...
  • Winther, Hans Arnold (Master thesis / Masteroppgave, 2010)
    We investigate scalar-field theories with a field-dependent coupling to matter and show the existence of a chameleon mechanism. The thin-shell solutions for a spherical body are found, and used to investigate the consequences ...
  • Zhang, B; David, L. P.; Jones, C.; Andrade-Santos, F.; O'Sullivan, E.; Dahle, Håkon; Nulsen, P. E. J.; Clarke, T. E.; Pointecouteau, E; Pratt, G. W.; Arnaud, M.; Vrtilek, J. M.; Ji, L.; van Weeren, R. J.; Kraft, R. P.; Kong, X. (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2015)
    We present Chandra and XMM-Newton observations of PLCK G036.7+14.9 from the Chandra–Planck Legacy Program. The high resolution X-ray observations reveal two close (~72'' = 193 kpc in projection) subclusters, G036N and ...
  • Drews, Ainar (Master thesis / Masteroppgave, 2014)
    In this thesis chromospheric features called Penumbral Microjets (PMJs) are investigated in a sunspot. Observations of high resolution in space, time and wavelength from the Swedish 1-meter Solar Telescope (SST) are used ...
  • Archontis, Vasilis; Hansteen, Viggo (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2014)
    We report on the formation of small solar flares produced by patchy magnetic reconnection between interacting magnetic loops. A three-dimensional (3D) magnetohydrodynamic (MHD) numerical experiment was performed, where a ...
  • Bull, Philip James; Wehus, Ingunn Kathrine; Eriksen, Hans Kristian Kamfjord; Ferreira, Pedro G.; Fuskeland, Unni; Górski, Krzysztof M.; Jewell, J. B. (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2015)
    In addition to primary fluctuations, cosmic microwave background (CMB) temperature maps contain a wealth of additional information in the form of secondary anisotropies. However, secondary effects that can be identified ...
  • Rubio da Costa, Fatima; Liu, Wei; Petrosian, Vahe; Carlsson, Mats (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2015)
    Solar flares involve complex processes that are coupled and span a wide range of temporal, spatial, and energy scales. Modeling such processes self-consistently has been a challenge in the past. Here we present results ...
  • Riemer-Sørensen, Signe; Parkinson, D.; Davis, T. M. (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2014)
    We present the strongest current cosmological upper limit on the neutrino mass of ∑mν<0.18  eV (95% confidence). It is obtained by adding observations of the large-scale matter power spectrum from the WiggleZ Dark Energy ...