Direct measurement of 4He(12C, 16O)γ reaction at KUTL.

A ¹²C+⁴He→¹⁶O+γ is regarded as the very important reaction to know the evolution of heavy stars. The cross section is, however, still unknown in spite of more than 40 years experiment in the world because of an existence of a resonance state of ¹⁶O at sub-threshold region. A cross section measurement with the direct detection of the produced ¹⁶O from E_cm = 2.4 downto 0.7 MeV have been planned at Kyushu University Tandem Laboratory(KUTL). Detection of the ¹⁶O is the most possible method at low energy, since a detection efficiency of the ¹⁶O is very high. The new windowless blow-in gas target was developed to achieve the pressure of 24 Torr. Many movable slit were installed in a recoil mass separator, so that the backgrounds generated by the ¹²C beam was eliminated effectively. The results of recent experiments at E_cm = 2.4 and 1.5 MeV are reported. [ABSTRACT FROM AUTHOR]