γ-ray spectroscopy in Λ hypernuclei

The present status of hypernuclear γ-ray spectroscopy with Hyperball is summarized. We observed two γ transitions of 16ΛO(1−→1−,0−) and obtained the strength of the ΛN tensor force. In 10B(K−,π−γ) data, we did not observe the spin-flip M1 transition of 10ΛB(2−→1−), but γ rays from hyperfragments such as 7ΛLi(7/2+→5/2+) and 9ΛBe(3/2+→1/2+) were observed. In 11B(π+,K+γ) data, we observed six γ transitions of 11ΛB. We also attempted an inclusive γ-ray measurement with a stopped K− beam.