The formation of small-scale umbral brightenings in sunspot atmospheres

  title={The formation of small-scale umbral brightenings in sunspot atmospheres},
  author={Chris J. Nelson and Vasco M. J. Henriques and Mihalis Mathioudakis and Francis P. Keenan},
  journal={Astronomy and Astrophysics},
Sunspot atmospheres have been shown to be highly inhomogeneous hosting both quasi-stable and transient features, such as small-scale umbral brightenings (previously named "umbral micro-jets") and dark fibril-like events. Aims. We seek to understand the morphological properties and formation mechanisms of small-scale umbral brightenings (analogous to umbral micro-jets). In addition, we aim to understand whether links between these events and short dynamic fibrils, umbral flashes, and umbral dots… 

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