First High-resolution Spectroscopic Observations of an Erupting Prominence Within a Coronal Mass Ejection by the Interface Region Imaging Spectrograph (IRIS)
arXiv:1502.04738 · doi:10.1088/0004-637X/803/2/85
Abstract
Spectroscopic observations of prominence eruptions associated with coronal mass ejections (CMEs), although relatively rare, can provide valuable plasma and 3D geometry diagnostics. We report the first observations by the Interface Region Imaging Spectrograph (IRIS) mission of a spectacular fast CME/prominence eruption associated with an equivalent X1.6 flare on 2014 May 9. The maximum plane-of-sky and Doppler velocities of the eruption are 1200 and 460 km/s, respectively. There are two eruption components separated by ~200 km/s in Doppler velocity: a primary, bright component and a secondary, faint component, suggesting a hollow, rather than solid, cone-shaped distribution of material. The eruption involves a left-handed helical structure undergoing counter-clockwise (viewed top-down) unwinding motion. There is a temporal evolution from upward eruption to downward fallback with less-than-free-fall speeds and decreasing nonthermal line widths. We find a wide range of Mg II k/h line intensity ratios (less than ~2 expected for optically-thin thermal emission): the lowest ever-reported median value of 1.17 found in the fallback material and a comparably high value of 1.63 in nearby coronal rain and intermediate values of 1.53 and 1.41 in the two eruption components. The fallback material exhibits a strong () linear correlation between the k/h ratio and the Doppler velocity as well as the line intensity. We demonstrate that Doppler dimming of scattered chromospheric emission by the erupted material can potentially explain such characteristics.
arXiv comment12 pages, 6 figures, accepted by ApJ (Feb 15, 2015)
References in corpus (22)
- The Interface Region Imaging Spectrograph (IRIS)
- Physics of Solar Prominences: II - Magnetic Structure and Dynamics
- Physics of Solar Prominences: I - Spectral Diagnostics and Non-LTE Modelling
- Observing the fine structure of loops through high resolution spectroscopic observations of coronal rain with the CRISP instrument at the Swedish Solar Telescope
- Advances in Observing Various Coronal EUV Waves in the SDO Era and Their Seismological Applications (Invited Review)
- The formation of IRIS diagnostics I. A quintessential model atom of Mg II and general formation properties of the Mg II h&k lines
- Double Coronal Hard and Soft X-ray Source Observed by RHESSI: Evidence for Magnetic Reconnection and Particle Acceleration in Solar Flares
- Coronal rain as a marker for coronal heating mechanisms
- The formation of IRIS diagnostics. III. Near-ultraviolet Spectra and Images
- What can we learn about solar coronal mass ejections, coronal dimmings, and Extreme-Ultraviolet jets through spectroscopic observations?
- An Intriguing Chromospheric Jet Observed by Hinode: I. Fine Structure Kinematics and Evidence of Unwinding Twists
- Far UV Spectra of Fast Coronal Mass Ejections Associated with X-class Flares
- Chromospheric Jet and Growing "Loop" Observed by Hinode: New Evidence of Fan-Spine Magnetic Topology Resulting From Flux Emergence
- Multidimensional modeling of coronal rain dynamics
- Open questions on prominences from coordinated observations by IRIS, Hinode, SDO/AIA, THEMIS, and the Meudon/MSDP
- Tangled Magnetic Fields in Solar Prominences
- Soft X-ray Fluxes of Major Flares Far Behind the Limb as Estimated Using STEREO EUV Images
- Observations of Coronal Mass Ejections with the Coronal Multichannel Polarimeter
- UVCS/SoHO Catalog of Coronal Mass Ejections from 1996 to 2005: Spectroscopic Proprieties
- Kinematics and helicity evolution of a loop-like eruptive prominence
- Effect of motions in prominences on the helium resonance lines in the extreme ultraviolet
- Plasma diagnostic in eruptive prominences from SDO/AIA observations at 304 Å
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- Transition Region and Chromospheric Signatures of Impulsive Heating Events. I. Observations
- Magnetic field in atypical prominence structures: Bubble, tornado and eruption
- Stellar coronal mass ejections II. Constraints from spectroscopic observations
- Helical motions of fine-structure prominence threads observed by Hinode and IRIS
- Density Fluctuations in a Polar Coronal Hole
- Solar prominence diagnostics from non-LTE modelling of Mgii h&k line profiles
- Two-dimensional simulations of coronal rain dynamics. I. Model with vertical magnetic field and an unbounded atmosphere
- Modelling of Mg II lines in solar prominences
- High-resolution Observations of a Flux Rope with the Interface Region Imaging Spectrograph
- Relation of coronal rain originating from coronal condensations to interchange magnetic reconnection
- Statistical analysis of UV spectra of a quiescent prominence observed by IRIS
- Comparing UV/EUV line parameters and magnetic field in a quiescent prominence with tornadoes
- Three-dimensional velocity fields of the solar filament eruptions detected by CHASE
- Rapid Rotation of an Erupting Prominence and the Associated Coronal Mass Ejection on 13 May 2013
- Revisiting the formation mechanism for coronal rain from previous studies
- Fast Magnetosonic Waves and Flows in a Solar Prominence Foot: Observations and Modeling
- From eruption to post-flare rain: a 2.5D MHD model
- Spectral evolution of an eruptive polar crown prominence with IRIS observations
- A new view of the solar interface region from the Interface Region Imaging Spectrograph (IRIS)