CME Initiation: The Matrix Reloaded

David Alexander, Rice University

Klimchuk Matrix (2000)

Model Multi-polar

Flux Rope

Sheared NL

Converg. Flow

Recon. Timing

Recon. Location

Mass Distrib.

Breakout Y NR Y NR at/before above NR

Flux Rope NR Y Y Y1 after1 below NR

NR2 at/after2

Tether Cutting

NR NR Y NR at/before below NR

Flux Injection

NR Y NR NR NR NR NR

Mass Loading

NR NR NR NR NR NR cavityand/or

prominence

What are the key observations that can discriminate among the models?

Pre-event solar atmospherePre-event solar atmosphere CME AccelerationCME Acceleration

Vector BChromospheric fieldPhotospheric flowsMagnetic morphologyEmerging/canceling fluxRole of reconnectionRole of flares Role of filamentsMagnetic complexityHelicity evolutionFluxrope formationTriggering phenomena …

Accurate H-T and V-T profilesLocation of peak accelerationRole of solar windRelationship to magnetic cloudsInteraction with IP medium Flare vs. prominence divideRole of helicity (expulsion?)Changes in magnetic topologyEruption of sheared core fieldTiming/location of reconnectionProduction of shocksWave activity …

Modeling

Initial + boundary conditionsPhysical assumptionsDriving mechanismambient conditions

ReconnectionHeating, Cooling

Particle accelerationShock formation

…

Ultimate challenge: determine key observational/modeling overlaps and utilize these to provide most appropriate I.C.s and most useful comparisons of model outputs

Understanding the CME process observationallyUnderstanding the CME process observationally

Pre-event solar atmospherePre-event solar atmosphere CME AccelerationCME Acceleration

Observational needs: high cadence vector B high cadence continuum H filament obs. (inc. Doppler)

Modeling needs: include reconnection physics (particles?) inc. observed field configurations and evolution investigate role of emerging/canceling flux incorporate flow fields track helicity ….

Observational needs: high cadence low-to-high coronal multi-

wavelength observations stereoscopically derived morphology and

velocity evolution

Modeling needs: specify factors which determine acceleration identify correct boundary conditions how do models distinguish between fast and slow events identify model discriminators in the data

How do we define a realistic challenge and how do we meet it?How do we define a realistic challenge and how do we meet it?3 approaches:

- wait until spatial, temporal resolution and source region complexity can be incorporated

- Tackle in detail an individual event (e.g. 1997 May 12)

- select 2-3 common phenomena which can be realistically incorporated into the ‘generic’ models

e.g. kinking,

failed-partial-full eruption, reformation of pre-eruption configuration

Non-starter

Providing great insight and driving model development

Broader application to common processes describing events

Example template of dialog matrix: models

The Matrix ReloadedModel M1 (2.5D) M2 (3D) … …

Basic BC

Basic Geom. Arcade Fluxrope multipolarBasic concept

Driving force shear Loss of

equilibrium Reconnection

above

B field Y (vector) YH / He 1083 dynamics

EUV/X-ray Y (morphology)

M

Coronagraph Y YSolar Wind ?

Particles NR

Assumptions/challenges

Sensitivity tests

Observational needs

Shear profile

Definition

of Model

Observational

input/comparison

Improving

models

Example template of dialog matrix: observations

The Matrix ReloadedObservation Magnetic Field Coronal

(EUV/X-ray)Coronagraph Solar Wind …

f-o-v/resolution

cadence

morphology

dynamics

Energy release

…

Pre-eruption

Post-eruption

Flow maps

Topology

Assumptions/challenges

coalignment

Control groups

…

Observational

characteristics

Relationship

to model

parameters

Improving

observations

Dialog template would have additional fields for

• Definitions and nomenclature

• Brief discussions • Physical quantities: input data/ parameters, output observables, methods for direct comparisons• Specify the metric and basis for comparisons

• Key references

• Point-counterpoint• Emphasis on specific argument and evidence; new observations needed to resolve issues