Catálogo de publicaciones - revistas

<jats:title>ABSTRACT</jats:title> <jats:p>Transition region explosive events (EEs) have been observed with slit spectrographs since at least 1975, most commonly in lines of C <jats:sc>iv</jats:sc> (1548 Å, 1550 Å) and Si <jats:sc>iv</jats:sc> (1393 Å, 1402 Å). We report what we believe to be the first observation of a transition region EE in He <jats:sc>ii</jats:sc> 304 Å. With the <jats:italic>Multi-Order Solar EUV Spectrograph</jats:italic> (<jats:italic>MOSES</jats:italic>) sounding rocket, a novel slitless imaging spectrograph, we are able to see the spatial structure of the event. We observe a bright core expelling two jets that are distinctly non-collinear, in directions that are not anti-parallel. The jets have sky-plane velocities of order 75 km s<jats:sup>−1</jats:sup> and line-of-sight velocities of +75 km s<jats:sup>−1</jats:sup> (blue) and −30 km s<jats:sup>−1</jats:sup> (red). The core is a region of high non-thermal Doppler broadening, characteristic of EEs, with maximal broadening 380 km s<jats:sup>−1</jats:sup> FWHM. It is possible to resolve the core broadening into red and blue line-of-sight components of maximum Doppler velocities +160 km s<jats:sup>−1</jats:sup> and −220 km s<jats:sup>−1</jats:sup>. The event lasts more than 150 s. Its properties correspond to the larger, long-lived, and more energetic EEs observed in other wavelengths.</jats:p>