Now showing items 166-185 of 523

  • Cheung, Mark C. M.; De Pontieu, Bart Walter; Tarbell, Theodore D.; Fu, Y.; Tian, H.; Testa, Paola; Reeves, K. K.; Martinez-Sykora, Juan; Boerner, P.; Wulser, J. P.; Lemen, J.; Title, Alan M.; Hurlburt, N.; Kleint, L.; Kankelborg, C.; Jaeggli, S.; Golub, L.; McKillop, S.; Saar, S.; Carlsson, Mats; Hansteen, Viggo (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2015)
    We report on observations of recurrent jets by instruments on board the Interface Region Imaging Spectrograph, Solar Dynamics Observatory (SDO), and Hinode spacecraft. Over a 4 hr period on 2013 July 21, recurrent coronal ...
  • de Jorge Henriques, Vasco Manuel; Mathioudakis, M.; Socas-Navarro, H.; de la Cruz Rodriguez, Jaime (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)
    We perform non-LTE inversions in a large set of umbral flashes, including the dark fibrils visible within them, and in the quiescent umbra by using the inversion code NICOLE on a set of full Stokes high-resolution Ca ii ...
  • Smith, Brent M.; Windhorst, Rogier A.; Jansen, Rolf A.; Cohen, Seth H.; Jiang, Linhua; Dijkstra, Mark; Koekemoer, Anton M.; Bielby, Richard; Inoue, Akio K.; MacKenty, John W.; O'Connell, Robert W.; Silk, Joseph I. (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)
    We present observations of escaping Lyman Continuum (LyC) radiation from 34 massive star-forming galaxies (SFGs) and 12 weak AGN with reliably measured spectroscopic redshifts at $z\simeq 2.3\mbox{--}4.1$. We analyzed ...
  • Hammami, Amir; Llinares, Claudio; Mota, David; Winther, Hans Arnold (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2015)
    In this paper, we present the first results from implementing two scalar–tensor modified gravity theories, the symmetron and the Hu–Sawicki f(R)-gravity model, into a hydrodynamic N-body code with dark matter particles and ...
  • Kowalski, Adam F.; Allred, Joel C.; Uitenbroek, Han; Tremblay, Pier-Emmanuel; Brown, Stephen; Carlsson, Mats; Osten, R. A.; Wisniewski, John P.; Hawley, Suzanne L. (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)
    The broadening of the hydrogen lines during flares is thought to result from increased charge (electron, proton) density in the flare chromosphere. However, disagreements between theory and modeling prescriptions have ...
  • Golding, Thomas Peter (Master thesis / Masteroppgave, 2010)
    The solar chromosphere is a region where the thermodynamics are out of equilibrium, and realistic values of temperature and electron densities here are difficult to obtain. Hydrogen, being the most abundant element in solar ...
  • Capparelli, Vincenzo; Zuccarello, Francesca; Romano, Paolo; Simões, Paulo J. A.; Fletcher, Lyndsay; Kuridze, D.; Mathioudakis, M.; Keys, Peter H.; Cauzzi, Gianna; Carlsson, Mats (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)
  • Kuridze, D.; Mathioudakis, M.; Simoes, P. J. A.; Rouppe, Van Der Voort Luc; Carlsson, Mats; Jafarzadeh, Shahin; Allred, J. C.; Kowalski, Adam F.; Kennedy, M; Fletcher, L.; Graham, D.; Keenan, F. P. (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2015)
    The asymmetries observed in the line profiles of solar flares can provide important diagnostics of the properties and dynamics of the flaring atmosphere. In this paper the evolution of the Hα and Ca ii λ8542 lines are ...
  • Engvold, Oddbjørn (Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)
    The IAU promotes astronomy as a tool to strengthen science education of young people in developing regions through its International Schools for Young Astronomers (ISYA) and a Teaching for Astronomy Development (TAD) ...
  • Kanella, Charalambos; Gudiksen, Boris Vilhelm (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)
    Context. The solar coronal heating problem has been an open question in the science community since 1939. One of the proposed models for the transport and release of mechanical energy generated in the sub-photospheric ...
  • Vanzella, E.; Balestra, I.; Gronke, Max Balthasar; Karman, W.; Caminha, G. B.; Dijkstra, Mark; Rosati, P.; De Barros, S.; Caputi, K.; Grillo, C.; Tozzi, P.; Meneghetti, M.; Mercurio, A.; Gilli, R. (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)
    We report the identification of extended Lyα nebulae at z ≃ 3.3 in the Hubble Ultra Deep Field (HUDF, ≃40 kpc × 80 kpc) and behind the Hubble Frontier Field galaxy cluster MACSJ0416 (≃40 kpc), spatially associated with ...
  • Klevas, J.; Kučinskas, A.; Wedemeyer, Sven; Ludwig, H.-G. (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)
    We use 3D magnetohydrodynamic CO5BOLD model atmospheres to study the interplay between magnetic fields and convection in the atmospheres of red giant stars. We find that vortex-like structures occur prominently in stars ...
  • Martinez-Sykora, Juan; De Moortel, Ineke; De Pontieu, Bart Walter; Hansteen, Viggo; Carlsson, Mats (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)
    The role of type II spicules in the corona has been a much debated topic in recent years. This paper aims to shed light on the impact of type II spicules in the corona using novel 2.5D radiative MHD simulations, including ...
  • Antolin, Patrick (Doctoral thesis / Doktoravhandling, 2012)
  • Toresen, Mikael (Master thesis / Masteroppgave, 2015)
    In this thesis we have implemented a basic radiative transfer code to model the radial Lyα scattering rate around the epoch when the first stars and galaxies start forming, and ionizing their surroundings. The model, builds ...
  • Svalheim, Trygve Leithe (Master thesis / Masteroppgave, 2018)
    The Planck satellite has provided a multitude of data images of the full microwave sky, or sky maps, since it saw first light in 2009. Its observations of the Cosmic Microwave Background (CMB) data has been paramount in ...
  • Sekse, Dan Henrik (Doctoral thesis / Doktoravhandling, 2013)
  • Ishikawa, R.; Trujillo Bueno, J.; Uitenbroek, Han; Kubo, M.; Tsuneta, S.; Goto, M.; Kano, R.; Narukage, N.; Bando, T.; Katsukawa, Y.; Ishikawa, S.; Giono, G.; Suematsu, Y.; Hara, H.; Shimizu, T.; Sakao, T.; Winebarger, A.; Kobayashi, K.; Cirtain, J.; Champey, P.; Auchère, F.; Stepan, Jiri; Belluzzi, L.; Asensio Ramos, A.; Manso Sainz, R.; De Pontieu, Bart Walter; Ichimoto, K.; Carlsson, Mats; Casini, R. (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)
    The Chromospheric Lyman-Alpha Spectro-Polarimeter is a sounding rocket experiment that has provided the first successful measurement of the linear polarization produced by scattering processes in the hydrogen Lyα line ...
  • Wulser, J. P.; Jaeggli, S.; De Pontieu, Bart Walter; Tarbell, T; Boerner, P.; Freeland, S.; Liu, W.; Timmons, R.; Brannon, S; Kankelborg, C.; Madsen, C; McKillop, S.; Prchlik, J; Saar, S.; Schanche, N; Testa, P; Bryans, P.; Wiesmann, Martin (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)
    The Interface Region Imaging Spectrograph (IRIS) is a NASA small explorer mission that provides high-resolution spectra and images of the Sun in the 133 – 141 nm and 278 – 283 nm wavelength bands. The IRIS data are archived ...
  • Pereira, Tiago Mendes Domingos; De Pontieu, Bart Walter; Carlsson, Mats; Hansteen, Viggo; Tarbell, T.D.; Lemen, J.; Title, A.; Boerner, P.; Hurlburt, N.; Wulser, J. P.; Martinez-Sykora, Juan; Kleint, L.; Golub, L.; McKillop, S.; Reeves, K. K.; Saar, S.; Testa, Paola; Tian, H; Jaeggli, S.; Kankelborg, C. (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2014)
    Solar spicules have eluded modelers and observers for decades. Since the discovery of the more energetic type II, spicules have become a heated topic but their contribution to the energy balance of the low solar atmosphere ...