Experimental study of neutrino absorption on carbon

The process of electron emission from {~}30 MeV neutrino absorption on carbon, ¹²C(νₑ,e^-{)}¹²$N, has been observed. The flux-weighted total cross section for the exclusive neutrino-induced nuclear transition $¹²C$(${{ν}}ₑ$,${e}^{{{-}}})¹²N(g.s.) is [1.05±{}0.10(stat)±{}0.10(syst)]×{}10^-41 cm². The measured cross section and angular distribution d{σ}/d{Ω} are in agreement with theoretical estimates. The inclusive νₑ ¹²C reaction rate, which accounted for the majority of all neutrino interactions observed in this experiment, was determined from a detailed fit of energy and angular distributions for the observed electrons. The inclusive ¹²C(νₑ,e^-)X cross section is measured to be [1.41±{}0.23(tot)]×{}10^-41 cm². An upper limit for the sum of the ¹³C(νₑ,e^-)X+²⁷Al(νₑ,e^-)X inclusive absorption cross sections is presented.