WHOLE SUN MONTH WORKING GROUPS

The scientific goals of Whole Sun Month (WSM) are organized below into five working groups. We have listed the observational inputs that could be made available with the name of the contact for the data (see mailing list for addresses). We have also listed specific modeling projects that were proposed during the WSM workshop. If you are interested in working on any of these projects, or have ideas for other projects supporting the working group goals, please contact Doug Biesecker or Sarah Gibson The names in parentheses after some of the modeling projects are people who have already expressed a definite interest in working on the project (this does not exclude others from collaborating with them). Projects with no names are ones that came up in discussion, but which have no definite participants as yet.

1) Morphology of 3-d corona

Overall goal: Determine the 3-d morphology of the WSM corona- i.e., where and what shape are the streamers, where are the coronal hole boundaries and how do they vary with height.

Observational inputs:

LASCO pB and Brightness images (Biesecker)

red line/green line C1 images (Korendyke)

UVCS OVI and Ly-alpha daily images (Kohl)

CDS streamer/coronal hole boundaries (Fludra)

SUMER streamer/coronal hole boundaries (Hassler)

MDI photospheric field (Hoeksema)

Kitt Peak chromospheric field (Bromage,JHarvey)

Sac Peak red line/green line coronal images (Altrock,Biesecker)

Mauna Loa pB (Gibson,Lecinski)

Yohkoh East+West offset images (Alexander)

SWAN full sky maps of Lyman-alpha (Summanen)

Specific modeling projects leading to overall goal:

Use pB to model f corona, subtract from Brightness images, increase 3-d resolution (Biesecker)

Use lower coronal observations to trace streamers down from corona at limb; see how they project on disk

Extrapolate photospheric field to estimate where field lines are open/closed (Hoeksema, Zhao)

Map coronal hole boundaries from lower coronal observations through upper coronal observations (possibly also down through chromospheric field observations to photospheric field) (Gibson, Hoeksema, Bromage, del Zanna)

Study polar plume morphology (Kopp, DeForest)

Use polarized Brightness (pB), Brightness, and polarization together to gain information about the 3-d structure along the line of sight (they have different scattering kernals.)

Compare white light structures and red line/green line structures to Ly-alpha and OVI structures in upper corona, as well as to lower coronal structures seen in emission (Giordano, Korendyke)

Calculate analytic representation of 3-d structures of corona (Guhathakurta, Biesecker, Gibson)

Correlate SWAN full sky Lyman-alpha maps with coronal images (poss. also in situ obs) (Summanen)

*** Note - in all of these studies we will keep in mind the different quantities (various densities, temperatures) to which the different observations are sensitive, affecting how the "global" morphology appears to them.***

2) "Solar minimum" streamer/hole modeling

Overall goal: determine maps of density, temperature, magnetic field, and velocity in the region 1 - 3 Rsun. As this is a formidable task, we will focus on a subset of the data.

Specifically, we will model three features:

2) the SE quadrant streamer, roughly centered on day 233 (Aug 20)

3) the North coronal hole, centered on day 237 (Aug 24).

This analysis will also serve as cross-calibration between instruments.

Observational inputs:

Mauna Loa pB (Gibson,Lecinski)

UVCS pB (Romoli)

LASCO C1 red, green line observations (Korendyke)

UVCS line intensities and profiles (Kohl, Antonucci)

CDS line intensities and profiles (Fludra)

SUMER line intensities and profiles (Hassler)

EIT line intensities (Thompson)

MDI photospheric field (Hoeksema)

YOHKOH line intensities (Alexander)

Sac Peak red, green line observations (Altrock,Biesecker)

Specific modeling projects leading to overall goal:

Calculate physical parameters using UVCS (Giordano, Romoli)

Calculate physical parameters using CDS (Fludra)

Calculate physical parameters using YOHKOH (Alexander)

Calculate physical parameters using SUMER (Hassler)

Calculate 2-d Ne maps from pB using V de Hulst inversions (Guhathakurta, Bagenal)

Calculate 2-d maps of Ne, B, T using magnetostatic models (use UVCS outflow velocities to test static assumption). (Bagenal, Gibson)

Calculate filling factors (Fineschi)

Compare pB to Lyman alpha (where outflow is low)

Calculate temperature from hydrostatic density models. (Guhathakurta)

Calculate temperature from ionization balance.

Calculate temperature from Ulysses charge states (uses density structures in streamer and coronal hole plus ion velocity profiles from UVCS) (Ko, Strachan)

Study velocity distribution in streamers, holes and plumes (Kohl, Antonucci)

Calculate coronal magnetic field from photospheric field extrapolations. (Hoeksema)

3) Detailed study of an equatorial coronal hole: the "elephant's trunk"

(or "tusk")

Overall goal: Study the evolution, morphology and physical properties of the WSM equatorial coronal hole

Observational inputs:

CDS coronal hole boundary study (Fludra,Bromage,Del Zanna)

SUMER full sun images that include elephant's trunk (Hassler)

MDI photospheric field (Hoeksema)

Kitt Peak chromospheric field (Bromage,JHarvey)

Yohkoh images including elephants trunk (Alexander)

UVCS limb passages of elephant's trunk

Specific modeling projects leading to overall goal:

Study the morphology of the eq. coronal hole (del Zanna, Hassler, Bromage)

Study the evolution of the eq. coronal hole boundaries (Bromage)

Possibly study dynamical changes in UVCS observations as trunk passes beneath the limbs (Antonucci, Giordano)

4) MHD wind extrapolations along flux tubes

Overall goal: Use the magnetic topology determined from modeled coronal field and morphological observations of coronal hole boundaries and plumes to determine appropriate flux tubes along which to evolve a wind. Use data products of working group 2 to establish boundary conditions. Compare the predictions of these wind models to in situ observations.

Observational inputs:

CELIAS solar wind parameters and composition Galvin

WIND MFI magnetometer data Lepping/Szabo

WIND SWI particle data Steinberg

ULYSSES magnetometer data Forsyth

ULYSSES SWOOPS particle data Riley

Specific modeling projects leading to overall goal:

Model wind along flux tubes at coronal hole boundary and at poles. Use data products of Working group 2 (i.e. densities, temperatures) as boundary conditions.

Compare to UVCS velocities and dynamics.

Compare model predictions of solar wind parameters to in situ observations.

5) Structural connection between corona and in situ observations.

Overall goal: Identify specific coronal structures that match structures observed in the solar wind.

Observational inputs:

MDI heliospheric current sheet predictions Hoeksema

CELIAS solar wind parameters and composition Galvin

WIND MFI magnetometer data Lepping/Szabo

WIND SWI particle data Steinberg

ULYSSES magnetometer data Forsyth

ULYSSES SWOOPS particle data Riley

Specific modeling projects leading to overall goal:

Connect coronal holes (particularly the elephant's trunk) with in situ manifestations. (Lazarus, Steinberg)

Possibly use WSM morphology to study magnetic cloud event of August 7, 1996. (Lepping)