UVCS/SoHO Catalog of Coronal Mass Ejections from 1996 to 2005: Spectroscopic Proprieties

TL;DR

This paper presents a comprehensive catalog of 1059 ultraviolet spectra of CMEs observed by SoHO/UVCS from 1996 to 2005, providing valuable diagnostics of plasma parameters and linking UV and white-light observations.

Contribution

It introduces a systematic catalog of CME UV spectra, including detailed diagnostics and features, based on a large dataset covering nearly a full solar cycle, which was not previously available.

Findings

UV detection favors faster, more massive CMEs

Approximately 40% of events have plasma velocity measurements

Most common structure detected is cool prominence material

Abstract

Ultraviolet spectra of the extended solar corona have been routinely obtained by SoHO/UVCS since 1996. Sudden variations of spectral parameters are mainly due to the detection of Coronal Mass Ejections (CMEs) crossing the instrumental slit. We present a catalog of CME ultraviolet spectra based upon a systematic search of events in the LASCO CME catalog, and we discuss their statistical properties. Our catalog includes 1059 events through the end of 2005, covering nearly a full solar cycle. It is online available at the URL http://solarweb.oato.inaf.it/UVCS_CME and embedded in the online LASCO CME catalog (http://cdaw.gsfc.nasa.gov/CME_list). The emission lines observed provide diagnostics of CME plasma parameters, such as the light-of-sight velocity, density and temperature and allow to link the CME onset data to the extended corona white-light images. The catalog indicates whether there are clear signatures of features such as shock waves, current sheets, O VI flares, helical motions and which part of the CME structures (front, cavity or prominence material) are detected. The most common detected structure is the cool prominence material (in about 70% of the events). For each event, the catalog also contains movie, images, plots and information relevant to address detailed scientific investigations. The number of events detected in UV is about 1/10 of the LASCO CMEs, and about 1/4 of the halo events. We find that UVCS tends to detect faster, more massive and energetic CME than LASCO and for about 40% of the events events it has been possible to determine the plasma light-of-sight velocity.