SUMER, UVCS and LASCO Observations of Small-Scale Ejecta

TitreSUMER, UVCS and LASCO Observations of Small-Scale Ejecta
Type de publicationConference Paper
Year of Publication2004
AuteursTeriaca, L., Curdt W., and Poletto G.
ÉditeurLacoste, H.
Conference NameSOHO 13 Waves, Oscillations and Small-Scale Transients Events in the Solar Atmosphere: Joint View from SOHO and TRACE
Date PublishedJan

During the fall 2002 SOHO-Sun-Ulysses quadrature, coordinated SUMER/UVCS observations were carried out off the west limb. Data were acquired over six consecutive days in several lines formed in the 2 104 - 106 K temperature range. The center of the SUMER slit was placed around 1.13 R and oriented in the north south direction, while the UVCS slit was set tangent to the solar limb at altitudes ranging between 1.6 and 2.1 R. On 19 and 20 November SUMER observed repeated transient events characterized by a strong increase of the intensity of transition region and Hydrogen Lyman and lines with large line broadenings and line of sight velocities, while little if any variation is seen in lines formed around 106 K. The duration of these events varies between 10-15 minutes up to 1 hour. The SUMER events are associated to streamer-like outflows seen in LASCO images and, in the case of the larger 19 November event, with a small jet travelling at \~ 400 km/s across the LASCO C2 fiel of view.