Browsing Institutt for teoretisk astrofysikk by Title

Now showing items 999-1018 of 1278

  • Radiation-pressure Waves and Multiphase Quasar Outflows 
    Mas Ribas, Lluis (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)
    We report on quasar outflow properties revealed by analyzing more than 60 composite outflow spectra built from ~60,000 C iv absorption troughs in the SDSS-III/BOSS DR12QBAL catalog. We assess the dependences of the equivalent ...
  • RADYN Simulations of Non-thermal and Thermal Models of Ellerman Bombs 
    Hong, Jie; Carlsson, Mats; Ding, M. D. (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)
    Ellerman bombs (EBs) are brightenings in the Hα line wings that are believed to be caused by magnetic reconnection in the lower atmosphere. To study the response and evolution of the chromospheric line profiles, we perform ...
  • RADYNVERSION: Learning to Invert a Solar Flare Atmosphere with Invertible Neural Networks 
    Osborne, Christopher M. J.; Armstrong, John A.; Fletcher, Lyndsay (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)
    During a solar flare, it is believed that reconnection takes place in the corona followed by fast energy transport to the chromosphere. The resulting intense heating strongly disturbs the chromospheric structure and induces ...
  • Rapid variations of Si IV spectra in a flare observed by interface region imaging spectrograph at a sub-second cadence 
    Lörinčík, Juraj; Polito, Vanessa; De Pontieu, Bart Walter; Yu, Sijie; Freij, Nabil (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
    We report on observations of highly-varying Si IV 1402.77 Å line profiles observed with the Interface Region Imaging Spectrograph (IRIS) during the M-class flare from 18 January 2022 at an unprecedented 0.8 s cadence. ...
  • Rates and delay times of Type Ia supernovae in the Dark Energy Survey 
    Wiseman, Philip; Sullivan, Mark; Smith, M.; Frohmaier, Christopher; Vincenzi, Maria; Graur, Or; Popovic, B.; Armstrong, P.; Brout, D.; Davis, Tamara M.; Galbany, Lluís; Hinton, Samuel R.; Kelsey, Lisa; Kessler, R.; Lidman, Chris; Möller, A.; Nichol, Robert C.; Rose, B.; Scolnic, Daniel; Toy, Michael D.; Zontou, Z.; Asorey, Jacobo; Carollo, Daniela; Glazebrook, K.; Lewis, Geraint F.; Tucker, B. E.; Abbott, Timothy M. C.; Aguena, Michel; Allam, Sahar; Andrade-Oliveira, F.; Annis, James; Bacon, D.; Bertin, Emmanuel; Brooks, D.; Buckley-Geer, Elizabeth; Burke, David L.; Carnero Rosell, Aurelio; Carrasco Kind, Matias; Carretero, Jorge; Costanzi, Matteo; da Costa, Luiz N.; Pereira, Maria Elidaiana da Silva; Desai, S.; Diehl, Herman T.; Doel, Peter; Everett, S.; Ferrero, Ismael; Flaugher, Brenna; Fosalba, Pablo; Frieman, Josh; García-Bellido, Juan; Gaztañaga, Enrique; Giannantonio, Tommaso; Gruen, Daniel; Gruendl, Robert A.; Gschwend, Julia; Gutierrez, G.; Hollowood, Devon L.; Honscheid, Klaus; Hoyle, B.; James, David J.; Krause, Elisabeth; Kuehn, Kyler; Kuropatkin, Nikolay; Maia, Marcio A. G.; Marshall, Jennifer L.; Martini, Paul; Menanteau, Felipe; Miquel, Ramon; Morgan, R.; Ogando, Ricardo L. C.; Palmese, Antonella; Paz-Chinchón, Francisco; Petravick, D.; Pieres, Adriano; Plazas Malagón, Andrés A.; Romer, A. K.; Sanchez, E.; Scarpine, Vic; Schubnell, M.; Serrano, Santiago; Sevilla-Noarbe, Ignacio; Soares-Santos, Marcelle; Suchyta, Eric; Swanson, Molly E. C.; Tarlé, Gregory; To, Chun-Hao; Varga, Tamas Norbert; Walker, Alistair R. (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
    We use a sample of 809 photometrically classified Type Ia supernovae (SNe Ia) discovered by the Dark Energy Survey (DES) along with 40 415 field galaxies to calculate the rate of SNe Ia per galaxy in the redshift range 0.2 ...
  • Rates and properties of Type Ia supernovae in galaxy clusters within the dark energy survey 
    Toy, M.; Wiseman, P.; Sullivan, M.; Frohmaier, C.; Graur, O.; Palmese, A.; Popovic, B.; Davis, T.M.; Galbany, L.; Kelsey, L.; Lidman, C.; Scolnic, D.; Allam, S.; Desai, S.; Abbott, T.M.C.; Aguena, M.; Alves, O.; Annis, J.; Bacon, D.; Bertin, E.; Brooks, D.; Burke, D.L.; Carnero Rosell, A.; Carrasco Kind, M.; Carretero, J.; Castander, F.J.; Conselice, C.; da Costa, L.N.; Pereira, M.E.S.; De Vicente, J.; Diehl, H.T.; Doel, P.; Everett, S.; Ferrero, Ismael; Frieman, J.; Gerdes, D.W.; Gruen, D.; Gruendl, R.A.; Gutierrez, G.; Hinton, S.R.; Hollowood, D.L.; Honscheid, K.; James, D.J.; Kuehn, K.; Kuropatkin, N.; Marshall, J.L.; Melchior, P.; Mena-Fernández, J.; Menanteau, F.; Miquel, R.; Pieres, A.; Plazas Malagón, A.A.; Romer, A.K.; Sanchez, E.; Scarpine, V.; Sevilla-Noarbe, I.; Smith, M.; Soares-Santos, M.; Suchyta, E.; Tarle, G.; To, C.; Weaverdyck, N. (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2023)
  • Reconnection brightenings in the quiet solar photosphere 
    Rouppe, Van Der Voort Luc; Rutten, Robert; Vissers, Gregal Joan Maria (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2016)
    We describe a new quiet-Sun phenomenon which we call quiet-Sun Ellerman-like brightenings (QSEB). QSEBs are similar to Ellerman bombs (EB) in some respects but differ significantly in others. EBs are transient brightenings ...
  • Reconstructing the inflaton potential 
    Huse, Tor Helge (Master thesis / Hovedoppgave, 2005)
    During inflation, the potential of the inflaton scalar field $\phi$, drives the exponential expansion of the Universe. The nature of the inflaton potential is presently unknown, but one hopes to learn more from observations ...
  • Recovering Thermodynamics from Spectral Profiles Observed by IRIS. (II). Improved Calculation of the Uncertainties Based on Monte Carlo Experiments 
    Sainz Dalda, Alberto; De Pontieu, Bart Walter (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2023)
    Abstract Observations by the Interface Region Imaging Spectrograph (IRIS) of the Mg ii h & k spectral lines have provided a new diagnostic window toward knowledge of the complex physical conditions in the ...
  • Recovering Thermodynamics from Spectral Profiles observed by IRIS: A Machine and Deep Learning Approach 
    Sainz Dalda, Alberto; de la Cruz Rodriguez, Jaime; De Pontieu, Bart Walter; Gošić, Milan (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)
    Inversion codes allow the reconstruction of a model atmosphere from observations. With the inclusion of optically thick lines that form in the solar chromosphere, such modeling is computationally very expensive because a ...
  • The Reduced Visibility of Lyman-alpha Flux from Galaxies at z > 6 due to Evolving Gas Kinematics 
    Barve, Christopher Backløf (Master thesis / Masteroppgave, 2016)
    Recent observations support a significantly reduced visibility of Lyman-α (Lyα) flux from galaxies at redshifts z > 6. This is surprising considering that the visibility of Lyα flux has been observed to increase up towards ...
  • Reflections on the photodissociation of CO in circumstellar envelopes 
    Groenewegen, Martin; Saberi, Maryam (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
    Carbon monoxide (CO) is the most abundant molecule after molecular hydrogen and is important for the chemistry in circumstellar envelopes around evolved stars. When modelling the strength and shape of molecular lines, the ...
  • Refuelled and shielded – the early evolution of tidal dwarf galaxies 
    Baumschlager, Bernhard; Hensler, Gerhard; Steyrleithner, Patrick; Recchi, Simone (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)
    We present, for the first time, numerical simulations of young tidal dwarf galaxies (TDGs), including a self-consistent treatment of the tidal arm in which they are embedded. Thereby, we do not rely on idealized initial ...
  • Releasing Scalar Fields: Cosmological Simulations of Scalar-Tensor Theories for Gravity Beyond the Static Approximation 
    Llinares, Claudio; Mota, David (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2013)
    Several extensions of general relativity and high energy physics include scalar fields as extra degrees of freedom. In the search for predictions in the nonlinear regime of cosmological evolution, the community makes use ...
  • Reply to: Signatures of sunspot oscillations and the case for chromospheric resonances 
    Jess, David B.; Snow, Ben; Fleck, Bernhard; Stangalini, Marco; Jafarzadeh, Shahin (Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2020)
  • Report - Institute of Theoretical Astrophysics 
    Unknown author (Series / Serietittel, 1950)
  • Resolving Clumpy versus Extended Lyα in Strongly Lensed, High-redshift Lyα Emitters 
    Navarre, Alexander; Khullar, Gourav; Bayliss, Matthew B.; Dahle, Håkon; Florian, Michael; Gladders, Michael; Kim, Keunho J.; Owens, M. Riley; Rigby, Jane; Roberson, Joshua; Sharon, Keren; Shibuya, Takatoshi; Walker, Ryan (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2024)
    We present six strongly gravitationally lensed Ly α emitters (LAEs) at z ∼ 4–5 with Hubble Space Telescope (HST) narrowband imaging isolating Lyα. Through complex radiative transfer Lyα encodes information about the spatial ...
  • Resonant absorption in expanding coronal magnetic flux tubes with uniform density 
    Howson, T. A.; de Moortel, Ineke; Antolin, Patrick; Van Doorsselaere, Tom; Wright, A. N. (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)
    Aims. We investigate the transfer of energy between a fundamental standing kink mode and azimuthal Alfvén waves within an expanding coronal magnetic flux tube. We consider the process of resonant absorption in a loop with ...
  • RESONANT ABSORPTION OF TRANSVERSE OSCILLATIONS AND ASSOCIATED HEATING IN A SOLAR PROMINENCE. I. OBSERVATIONAL ASPECTS 
    Okamoto, T. J.; Antolin, Patrick; De Pontieu, Bart Walter; Uitenbroek, Han; Van Doorsselaere, Tom; Yokoyama, T (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2015)
    Transverse magnetohydrodynamic waves have been shown to be ubiquitous in the solar atmosphere and can, in principle, carry sufficient energy to generate and maintain the Sun's million-degree outer atmosphere or corona. ...
  • Resonant line transfer in a fog: Using Lyman-alpha to probe tiny structures in atomic gas 
    Gronke, Max Balthasar; Dijkstra, Mark; McCourt, Michael; Peng Oh, S. (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2017)
    Motivated by observational and theoretical work that suggest very small-scale (≲ 1 pc) structure in the circumgalactic medium of galaxies and in other environments, we study Lyman-α (Lyα) radiative transfer in an extremely ...