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In this study, we consider chromospheric heating models for 55 Cancri inconjunction with observations. The theoretical models, previously discussed inPaper I, are self-consistent, nonlinear and time-dependent ab-initiocomputations encompassing the generation, propagation, and dissipation ofwaves. Our focus is the consideration of both acoustic waves and longitudinalflux tube waves amounting to two-component chromosphere models. 55 Cancri, aK-type orange dwarf, is a star of low activity, as expected by its age, whichalso implies a relatively small magnetic filling factor. The Ca II K fluxes arecomputed (multi-ray treatment) assuming partial redistribution andtime-dependent ionization. The theoretical Ca II H+K fluxes are subsequentlycompared with observations. It is found that for stages of lowest chromosphericactivity the observed Ca II fluxes are akin, though not identical, to thoseobtained by acoustic heating, but agreement can be obtained if low levels ofmagnetic heating - consistent with the assumed photospheric magnetic fillingfactor - are considered as an additional component; this idea is in alignmentwith previous proposals conveyed in the literature.

Chromospheric Activity in 55 Cancri: II. Theoretical Wave Studies versus Observations