Subject: Re: [Nessc] Oct 10 NESSC Meeting Summary
From: "Steven R. Cranmer" <[email-masked]>
To: [email-masked]
Date: Wed, 11 Oct 2006 12:02:29 -0400 (EDT)
List-Id: New England Space Science Consortium <nessc.bu-ast.bu.edu>

Hello,

> George then raised the possibility of a joint
> paper on the commonality of eruptive magnetic processes as
> a useful step toward IHY and a general application of heliospheric
> physics to astrophysics.

Sorry to come late to the game, but there are also several interesting
ideas about "plasmoids" regarding coronal heating and solar wind
acceleration.  The first regards the so-called "blobs" seen by
LASCO/SOHO at the tips of helmet streamers.  Wang et al.'s (2000,
JGR, 105, 25133) review paper covers the various theoretical
interpretations in terms of plasmoid buoyancy, reconnection, etc.
(see also Fisk & Schwadron 2001, ApJ, 560, 425 for more on
interchange reconnection).  These blobs are believed to act as
tracers of the solar wind acceleration, but not to carry the
majority of the mass flux.

There are also some old ideas about the diamagnetic acceleration
of buoyant plasmoids as helping to provide substantial momentum
to the overall solar wind.  Low-density plasmoids are pinched
off like "melon seeds" and help to "drag up" the surrounding
higher-density plasma.  I think they are supposed to gradually
come into gas pressure equilibrium with the surrounding plasma
(or break up via Kelvin-Helmholz instabilities?) and thus would
not be distinguishable in the in-situ heliosphere.
Schl\"uter (1957, IAU Symp. 4, 356) originally suggested this,
even prior to the continuous solar wind being known about, and
Pneuman (1986, Sp Sci Rev, 43, 105) picked up on it.  (For more
recent references, see section 4.3 of Cranmer 2002, Sp Sci Rev,
101, 229).

These also relate to models and observations of X-ray jets from the
tips of cuspy coronal field configurations (e.g., Yokoyama & Shibata
1996, PASJ, 48, 353), or to the UV jets that are sometimes seen
coming from polar plumes in coronal holes.

Anyway, if these additional topics would be useful to include
in a review paper, I'd be glad to do a bit of writing. (It's possible,
though, that the narrative focus might be best served by a SMALL list
of topics -- too many might weaken it...)

Steve
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