On the origin of solar white-light flares

Using the Hα line intensity as a constraint, we study the role of a chromospheric condensation and the role of nonthermal effects in producing the continuum enhancement of white-light flares. Within an acceptable range of Hα line intensities and electron energy flux, it is shown that neither a chromospheric condensation nor non-thermal effects alone can directly explain the observed continuum enhancement. The hybrid role of both chromospheric condensation and non-thermal effects can only lead to a Balmer jump, but still not to a significant continuum intensity increase between 4000 and 7000 Å. A possible picture is discussed, that is, the Balmer jump is directly produced by the association of a chromospheric condensation and of non-thermal effects, while the continuum enhancement between 4000 and 7000 Å is indirectly produced by the condensation and the non-thermal effects via radiative heating to the deeper photospheric layers.