NEUTRINO2010, XXIV International Conference on Neutrino Physics and Astrophysics, Athens, GREECE

Proposed experiment to measure $\gamma$-rays in high resolution hadron beam experiments $O(p,p’)X$ and $O(^3He,t)X$ and the detection of $\gamma$-rays in $\nu-^{16}O$ reactions

Not scheduled

1m

Aithousa Mitropoulos

Speaker

Mr Takaaki Mori (Okayama University)

Description

The $\gamma$-rays produced from excited nuclei in neutral-current (NC) neutrino-oxygen (even charged-current (CC) $\nu-O$) interactions have not been measured at $E_{\nu}=10-100$ MeV. They are very important, since they will add extra signals or become unexpected background in Supernova neutrino detection. Neutrinos at $E_{\nu}=20-100$ MeV are expected to excite $1^-$ , $1^+$ and $2^-$ (giant resonances) in NC reactions $O(\nu, \nu’)O^*$, which decay to $^{15}N^*+p$ and $^{15}O^*+n$; the $\gamma$-rays are produced from $^{15}N^*$ and $^{15}O^*$. But, no previous experiments have checked such expectations. We show a proposed experiment to measure the $\gamma$-ray spectrum produced in the hadron beam experiments $O(p,p’)X$ ($\Delta T$=0,1) and $O(^3He,t)X$ ($\Delta T$=1) at RCNP(Osaka). They will give the information on the Fermi and Gamov-Teller transition strength from the ground state to the excited states of the oxygen, associated with the $\gamma$-ray production. Such experiment will further develop an initial measurement of the $\gamma$-ray spectrum in $O(p,2p)N$ reaction at RCNP (K.Kobayashi et al., nucl-ex/0604006).