Now showing items 1-13 of 13

    • Bombs and flares at the surface and lower atmosphere of the Sun 

      Hansteen, V. H.; Archontis, V.; Pereira, T. M. D.; Carlsson, M.; Rouppe van der Voort, L.; Leenaarts, J. (2017-04-10) - Journal article
      A spectacular manifestation of solar activity is the appearance of transient brightenings in the far wings of the Hα line, known as Ellerman bombs (EBs). Recent observations obtained by the Interface Region Imaging ...
    • A cancellation nanoflare model for solar chromospheric and coronal heating 

      Priest, E. R.; Chitta, L. P.; Syntelis, P. (2018-08-01) - Journal article
      Nanoflare models for heating the solar corona usually assume magnetic braiding and reconnection as the source of the energy. However, recent observations at record spatial resolution from the SUNRISE balloon mission suggest ...
    • A fast and accurate method to capture the solar corona/transition region enthalpy exchange 

      Johnston, C. D.; Bradshaw, S. J. (2019-03-15) - Journal article
      The brightness of the emission from coronal loops in the solar atmosphere is strongly dependent on the temperature and density of the confined plasma. After a release of energy, these loops undergo a heating and upflow ...
    • Hα and EUV observations of a partial CME 

      Christian, Damian J.; Jess, David B.; Antolin, Patrick; Mathioudakis, Mihalis (2015-05-12) - Journal article
      We have obtained Hα high spatial and time resolution observations of the upper solar chromosphere and supplemented these with multi-wavelength observations from the Solar Dynamics Observatory (SDO) and the Hinode ...
    • The influence of the magnetic field on running penumbral waves in the solar chromosphere 

      Jess, David; Reznikova, V; Van Doorsselaere, Tom; Mackay, Duncan Hendry; Keys, Peter (2013-12-03) - Journal article
      We use images of high spatial and temporal resolution, obtained using both ground- and space-based instrumentation, to investigate the role magnetic field inclination angles play in the propagation characteristics of running ...
    • Magneto-static modeling from SUNRISE/IMaX : application to an active region observed with SUNRISE II 

      Wiegelmann, T.; Neukirch, Thomas; Nickeler, D. H.; Solanki, S. K.; Barthol, P.; Gandorfer, A.; Gizon, L.; Hirzberger, J.; Riethmüller, T. L.; Noort, M. van; Rodríguez, J. Blanco; Del Toro Iniesta, J. C.; Suárez, D. Orozco; Schmidt, W.; Pillet, V. Martínez; Knölker, M. (2017-03-22) - Journal article
      Magneto-static models may overcome some of the issues facing force-free magnetic field extrapolations. So far they have seen limited use and have faced problems when applied to quiet-Sun data. Here we present a first ...
    • Magneto-static modeling of the mixed plasma Beta solar atmosphere based on SUNRISE/IMaX data 

      Wiegelmann, Thomas; Neukirch, Thomas; Nickeler, Dieter; Solanki, Sami; Martinez Pillet, Valentin; Borrero, Juan Manule (2015-12) - Journal article
      Our aim is to model the 3D magnetic field structure of the upper solar atmosphere, including regions of non-negligible plasma beta. We use high-resolution photospheric magnetic field measurements from SUNRISE/IMaX as ...
    • A new approach for modelling chromospheric evaporation in response to enhanced coronal heating. I. The method 

      Johnston, Craig David; Hood, Alan William; Cargill, Peter; De Moortel, Ineke (2017-01) - Journal article
      We present a new computational approach that addresses the difficulty of obtaining the correct interaction between the solar corona and the transition region in response to rapid heating events. In the coupled corona, ...
    • Observations and numerical models of solar coronal heating associated with spicules 

      De Pontieu, Bart; De Moortel, Ineke; Martinez-Sykora, Juan; McIntosh, Scott (2017-08-18) - Journal article
      Spicules have been proposed as significant contributors to the mass and energy balance of the corona. While previous observations have provided a glimpse of short-lived transient brightenings in the corona that are associated ...
    • On the connection between propagating solar coronal disturbances and chromospheric footpoints 

      Bryans, Paul; McIntosh, Scott W.; De Moortel, Ineke; De Pontieu, Bart (2016-09) - Journal item
      The Interface Region Imaging Spectrograph (IRIS) provides an unparalleled opportunity to explore the (thermal) interface between the chromosphere, transition region, and the coronal plasma observed by the Atmospheric Imaging ...
    • Resonant absorption of transverse oscillations and associated heating in a solar prominence. I. Observational aspects 

      Okamoto, Takenori J.; Antolin, Patrick; De Pontieu, Bart; Uitenbroek, Han; Van Doorsselaere, Tom; Yokoyama, Takaaki (2015-08-11) - Journal article
      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. ...
    • Transverse wave induced Kelvin-Helmholtz rolls in spicules 

      Antolin, Patrick; Schmit, Don; Pereira, Tiago M. D.; De Pontieu, Bart; De Moortel, Ineke (2018-03-23) - Journal article
      In addition to their jet-like dynamic behaviour, spicules usually exhibit strong transverse speeds, multi-stranded structure and heating from chromospheric to transition region temperatures. In this work we first analyse ...
    • Validation of the magnetic energy vs. helicity scaling in solar magnetic structures 

      Tziotziou, K.; Moraitis, K.; Georgoulis, M.K.; Archontis, V. (2014-10) - Journal item
      Aims. We assess the validity of the free magnetic energy - relative magnetic helicity diagram for solar magnetic structures. Methods. We used two different methods of calculating the free magnetic energy and the relative ...