Issues and status of “basic divertor and SOL physics” from papers and discussions

⁴⁸Ca, the lightest double beta decay candidate, has been until now the only one simple enough to be treated exactly in the nuclear shell model. Thus, theββ(2ν) half-life measurement, reported here, provides a unique test of the nuclear physics involved in theββ matrix element calculation. Enriched⁴⁸Ca sources of two different thicknesses have been exposed in a time projection chamber, and yieldT ₁ ^2/2ν =(4.3 _−1.1 ^+2.4 stat.] ± 1.4syst.]) × 10¹⁹ years, compatible with the shell model calculations. The consequences of this result for the shell model calculation of theββ(2ν) rate are briefly discussed. Presented by P. Vogel at the Workshop on calculation of double-beta-decay matrix elements (MEDEX’97), Prague, May 27–31, 1997. This work was funded by the US Department of Energy under contracts DE-FG03-01ER40679 and DE-FG03-88ER40397.