WHI WG 4: Transients

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WHI WG 4 Transients Tracing CMEs from Sun to
Earth and Beyond Group coordinator David Webb

• Science Goals
•  
• Origins/Initiation of CMEs (incl. Active
  regions/ Filaments/ Prominences)
• Multi-spectral analyses
• 3D viewpoints over large distances
• CMEs against relatively simple background
• Development evolution of current sheet (April
  9)
• Context within global evolution

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WHI WG 4 Participants in Session
Samaiyah Farid Toni Galvin Holly Gilbert Nat
Gopalswamy Jack Gosling Bernie Jackson Terry
Kucera Simon Plunkett Barbara Thompson Terry
Onsager Craig DeForest Dave Webb Jon Linker Scott
McIntosh From WG5 Deborah Haber Pat McIntosh
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WHI CMEs

• Discussed March 25, April 26-29, April 9
  related events April 4-7
• - All have good STEREO, SOHO coverage
• Mar 25 Apr 26 CMEs both fast CMEs with shocks
  (Type IIs)
• arcades, dimmings EUV waves
• - several ongoing studies papers already
• Apr 9 event is slower CME, erupting prom.,
  current sheet evolution
• - also ongoing studies papers
• - 2 - 3 earlier EPs, CMEs in same region
• Need a matrix of data and projects on events
• Need to identify source regions for all WHI CMEs
• Context of erupting regions within global
  evolution

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989 988 987
(992)
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CME in STEREO EUVISimon Plunkett
Running difference EUVI 171 Å
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CME in STEREO COR1
Running difference COR1 total brightness
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CME in STEREO COR2
Running difference COR2 total brightness
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CME in STEREO HI
Running difference HI1-A total brightness
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CME Height vs Time Profile

• Elongation of CME leading edge in STEREO-A
  converted to radial distance (height) assuming
  radial propagation from flare site.
• A. Thernisien doing 3D forward modeling CME
  direction of propagation within 5? of the radial
  from AR 989.
• V. Kunkel - Height, speed, and acceleration
  profiles compare well with J. Chens flux rope
  model.
• Initial rapid acceleration is followed by
  deceleration and propagation at approximately
  constant speed.
• Comparison with model best when CME is close to
  Sun.

Courtesy V. Kunkel
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Metric type II Bursts start when LASCO CME is
below the Occulting DiskNat Gopalswamy
No Type II at this time (1848)
Type II ended at 1900
Height of EIT eruption at 1848 UT 1.1 Ro
Height of LASCO CME at 1931 UT 5.79 Ro
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WAVES Type II
9 MHz ? 4.5 MHz ? 2.5x105 cm-3
CME height 5.79 Ro at 193136 UT
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Metric type II 1852 1900
1931 (WAVES type II end)
C3
From LASCO
C2
m t II Strt 4.0Ro
m t II End 3.5Ro
EIT 1.1 Ro
COR1 1.43 Ro
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Post-WHI CME 26-29 April 2008 Our only Sun-1
AU Connection Event?

• Arcade, dimming, EIT wave, type II (m), halo CME
  ST-B, LASCO
• Near Sun-center for
• STEREO-B Earth
• Small SEP at ST- B on 26 April MC at ST-B on
  29 April

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EUV Wave and COR1 CME when Type II Burst is in
ProgressN. Gopalswamy
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STEREO B Shock/MC A- Nothing
B- SEP A- Nothing
26 April
29 April
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April 26 CME tracked from Sun to STEREO-B incl.
with HI2A SMEI
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Mar. 25 Apr. 26 Studies

• Compare two events for waves, shocks, CME
  shapes, speeds, densities, esp. for blob and CME
  loop
• - Mar. event tracked to 40 deg. in HIs.
• - Apr. event tracked to STEREO-B in HIs and
  SMEI.
• - ENLIL IP model with cone or 3D construct as
  CME.
• Gopal paper for STEREO S.P. issue on CME Type
  II assoc.
• Alysha Reinart study arcades dimmings in 2
  events.
• Toni Galvin lead study of possible ejecta in
  ST-B in-situ data.
• - Fe charge states suggest CIR-type interface
• - Farrugia model flux rope signatures
• - Compare HI SMEI densities with in-situ

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Discussed next by Samaiya Farid
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CMS POTENTIAL FIELD
CMS/XRT..good match
CMS/STEREO
CMS/XRT..not so good match
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Post-erruption Inflow Velocities
Chevron Vertex Projected Downflow Speed
40,60,100 km/s
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Ongoing studies of April 9 event

• 1. The heating of the prominence using
  EIS/UVCS/EUVI and comparing w/ various models
  Miralles, Raymond, Landi, DeLuca, Stenborg
• 2. The pre-event configuration of the prominence
  and comparison of the April 5 and 9 events.
  Angelos will also provide to Aad observations of
  3 similar events at other times and will lead a
  SECCHI observational paper on oblique eruptions.
  -- van Ballegooijen, Su, Vourlidas, Stenborg
• 3. The forward modeling of the current sheet
  geometry and comparisons w/ LASCO/SECCHI/etc.
  Vourlidas, Kasper, Patsourakos, Webb, Stenborg
  STEREO Solar Physics Issue?
• 4. The size and energetics of the CME and
  prominence, comparison w/ flxurope models.
  Vourlidas, van Ballegooijen, Su, Reeves, Raymond,
  Forbes
• 5. Dynamics of the current sheet McKenzie,
  Savage, Reeves, Kasper, Webb, Forbes, Narukage,
  (Landi, if the EIS data is useful)
• 6. Modeling of the emission in the current sheet
  Ko, Webb, Landi, Vourlidas, Raymond, Reeves,
  Kasper

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• 2-3 CME/EP earlier related events April 4-7.
• Terry Kucera- CDS rasters of Apr. 9 prom. EIS,
  SUMER data?
• - Bill Thompson study of 3D reconsruction of
  prom. Eruption, EUVI
• Scott McIntosh Studies of Hinode EIS, Trace,
  etc. data on complexity
• of structures, dimmings, line widths
• - Effect on evolution of CMEs, in-situ
  effects, etc.
• - Difficulties for modelers!
• Discussion of global evolution in AR area with
  WG5
• - Deborah Haber on MDI helioseismological
  flows as f(depth)
• will do both for events and globally
• - Pat McIntosh comparison of these with
  changes in synoptic charts
• inconclusive
• - Possible vortex before Apr. 5-9 events
• - Flows also before Apr. 26 event

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D. Haber MDI flows CR 2068