Observation ofH Λ 4 Hyperhydrogen by Decay-Pion Spectroscopy in Electron Scattering
Physical Review Letters(2015)
摘要
At the Mainz Microtron MAMI, the first high-resolution pion spectroscopy from decays of strange systems was performed by electron scattering off a Be-9 target in order to study the ground-state masses of Lambda-hypernuclei. Positively charged kaons were detected by a short-orbit spectrometer with a broad momentum acceptance at zero degree forward angles with respect to the beam, efficiently tagging the production of strangeness in the target nucleus. In coincidence, negatively charged decay-pions were detected by two independent high-resolution spectrometers. About 10^3 pionic weak decays of hyperfragments and hyperons were observed. The pion momentum distribution shows a monochromatic peak at p_pi ~ 133 MeV/c, corresponding to the unique signature for the two-body decay of hyperhydrogen Lambda H-4 -> He-4 + pi-, stopped inside the target. Its binding energy was determined to be B_Lambda = 2.12 +- 0.01 (stat.) +- 0.09 (syst.) MeV with respect to the H-3 + Lambda mass.
更多查看译文
关键词
mathvariant=normal>λ</mmlmi></mmlmrow><mmlmrow><mmlmn>4</mmlmn></mmlmrow></mmlmmultiscripts></mmlmrow></mmlmath>hyperhydrogen,electron scattering,of<mmlmath xmlnsmml=http//wwww3org/1998/math/mathml,decay-pion
AI 理解论文
溯源树
样例
![](https://originalfileserver.aminer.cn/sys/aminer/pubs/mrt_preview.jpeg)
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要