Real-time notes from Locarno WG 2-4, Friday June 10 2005

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Introduction 

General problem
FIP enhancements and composition variable from flare to flare, according
  to the gamma rays
Trottet comment - there is some fraction from the corona in any case
Discussion of state of knowledge of interaction depth
Hurford-Share progress report on imaging 511 keV, a teaser
Discussion of FIP (Fletcher, Hudson, Lin)
Shih results in increasing FIP fraction in 3 flares
Phillips use of RESIK
CDS results from Young, Mason, Fletcher 
Dennis comment about Fe-feature access to FIP enhancement 
Gallagher comment about RESIK spectra ("Where is Janusz?")
Hudson comment about discrepancy between general FIP enhancement for
  gamma-rays, and naive ideas about particle propagation
Share discussion of pseudo-continuum resulting from very hard spectra (very
  extended at high energies)
Trottet comment about GeV region in big events (also Kocharov), CORONAS up
  to 100 MeV
Oct 28 CORONAS data show late phase with 100-MeV component, unlike BS 
  (Kuznetsov, Kurt et al. preprint)
Extensive debate about WLF origins, theoretical and observational (Dennis,
  Hudson, Share, Fletcher)
Should encourage getting WL observations understood - d'accord
Discussion of line shapes: Dennis and Hudson don't think the broad lines
  strongly exclude low temperatures
Narrow line from below the photosphere where ionization increases? 
  Johns-Krull suggestion of pressure ionization; Hudson suggestion of 
  Saha equilibrium and a check of Allen's Astrophysical Quantitities
January 20 long-duration 2.2 line (day/night modulation)
Fontenla idea (Dennis, MacKinnon shrug)

Hurford

Imaging of 511, intro and issues
Spectral overview
Optimizing S/N via light curve and spectral band: as wide and as long as
  possible
Grid 9
Expect 6.3 front s/n; 5.2 rear (nb independent) and can get centroids
Fluences are consistent mutually but much lower than Gerry's model
Imaged line fluence is 260+-100, or 35+-13% of prediction; five possible
  reasons for this 
Grid 6
Can't get consistent results, but could be structural
Future: can optimize spectral band better; can combine front and rear; can
  optimize imaging parameters