TRACE - derived temperature and emission measure pro les alonglong - lived coronal loops : the role of lamentation

نویسندگان

  • F. Reale
  • G. Peres
چکیده

In a recent letter (ApJ 517, L155) Lenz et al. have shown the evidence of uniform temperature along steady long coronal loops observed by TRACE in two diierent pass-bands (171 A and 195 A lters). We propose that such an evidence can be explained by the sub-arcsecond structuring of the loops across the magnetic eld lines. In this perspective , we present a model of a bundle of six thin parallel hydrostatic laments with temperature stratiication dictated by detailed energy balance and with temperatures at their apex ranging between 0.8 and 5 MK. If analyzed as a single loop, the bundle would appear isothermal along most of its length.

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تاریخ انتشار 2008