To foresee a solar flare neutrino signal we infer its upper and lower bound.
The upper bound was derived since a few years by general energy equipartition
arguments on observed solar particle flare. The lower bound, the most
compelling one for any guarantee neutrino signal, is derived by most recent
records of hard Gamma bump due to solar flare on January 2005 (by neutral pion
decay).The observed gamma flux reflects into a corresponding one for the
neutrinos, almost one to one. Therefore we obtain minimal bounds already at the
edge of present but quite within near future Megaton neutrino detectors. Such
detectors are considered mostly to reveal cosmic supernova background or rare
Local Group (few Mpc) Supernovas events. However Megaton or even inner ten
Megaton Ice Cube detector at ten GeV threshold may also reveal traces of solar
neutrino in hardest energy of solar flares. Icecube, marginally, too. Solar
neutrino flavors may shine light on neutrino mixing angles.Comment: 4 pages,4 figure