MAX MILLENNIUM COORDINATED OBSERVING
Goals | Ground Based Observatories |
Space Based Observatories | Target | Scheduling
||REGION LIKELY TO PRODUCE GREAT
Richard Canfield (firstname.lastname@example.org)
Montana State University
William Marquette (email@example.com)
||Version 6: 26 February 2015
||This plan describes context and flare observations from
ground-based and space-based instruments and observatories appropriate
to solar active regions that are likely to produce (1) flares with
either nuclear-line or high-energy gamma-ray emission that extends
above 50 MeV,
which are typically of GOES X (and high M) class, and are associated
with fast and wide CMEs, or (2) very large flares, with GOES
classification > X5, with or without such gamma-ray emission.
describes the circumstances under which the
Max Millennium Chief Observer will declare a Great Flare Watch.
Goal: To obtain multi-wavelength imaging and spectroscopic observations
before, during and after gamma-ray solar flares, which will be the
source of the most valuable and unique
spectra and images from RHESSI.
Approach: In a manner appropriate to each instrument, observatory,
and spacecraft, to observe, if at all possible,
the active region identified in
the Great Flare Watch message from the Max Millennium Chief Observer
to the Max Millennium Message
of the Day list.
The scientific goal of this program is to understand
energy release, particle acceleration, and particle and energy transport
in those flares that produce gamma-ray lines.
Key questions are:
Co-temporal data from ground and space-based observatories are crucial
to answering these questions.
What is the partition of energy between ions and electrons?
Where are ions accelerated, and what are the physical conditions
(temperature, density, velocity and magnetic fields) there?
What are the abundances of accelerated particles and the ambient
atmosphere at the Sun?
What mechanisms accelerate both electrons and ions to high energies so
rapidly and efficiently?
What mechanisms transport high-energy ions
away from the acceleration site?
What are the characteristic signatures of flares
that have potentially hazardous radiation effects?
What is the relationship between ion acceleration and CMEs?
The MM Chief Observer will choose an active region for this
observing program when either of the following criterion is met:
Active region has produced a flare that is
large (typically GOES X-class) and is associated with Fermi LAT nuclear-line or
high-energy gamma-ray emission, typically with a fast and broad CME (if
produced one such flare, it will probably produce at least one more).
Active region has an area > 1000
micro-hemispheres and is classified "beta-gamma-delta", and in addition has an
"Island Delta" sunspot configuration with the following
properties, of which the first three are most important:
- Within the common penumbra there is dominant umbra, usually of p
polarity, two or more surrounding umbrae of opposite polarity, and
additional surrounding umbrae of p polarity.
- The polarity structure is typically inverted, i.e., the westernmost umbra is f polarity.
- The umbrae making up the configuration emerge together, i.e., the
configuration does not form by merging or successive emergence of
- The common penumbra is surrounded by weaker flux whose polarity
is opposite that of the dominant umbra. The weaker flux is typically
the residual of a previous AR.
This is a target-of-opportunity plan. It will be called only when
there is a region on the disk or the limb that is likely to produce
a great flare, according to the criterion above.