  The detection of neutrinos from massive stellar collapses can teach us a lot
not only about source objects but also about microphysics working deep inside
them. In this study we discuss quantitatively the possibility to extract
information on the properties of dense and hot hadronic matter from neutrino
signals coming out of black-hole-forming collapses of non-rotational massive
stars. Based on our detailed numerical simulations we evaluate the event
numbers for SuperKamiokande with neutrino oscillations being fully taken into
account. We demonstrate that the event numbers from a Galactic event are large
enough not only to detect it but also to distinguish one hadronic equation of
state from another by our statistical method assuming the same progenitor model
and non-rotation. This means that the massive stellar collapse can be a unique
probe into hadron physics and will be a promising target of the nascent
neutrino astronomy.
