J-PARC \u30cf\u30c9\u30ed\u30f3\u5b9f\u9a13\u65bd\u8a2d\u306b\u304a\u3044\u3066\u5b9f\u65bd\u3057\u305f\u30b0\u30b6\u30a4\u30cf\u30a4\u30d1\u30fc\u6838\u5206\u5149\u5b9f\u9a13 (E70 \u5b9f\u9a13) \u306e\u30c7\u30fc\u30bf\u53d6\u5f97\u3092\u5b8c\u4e86\u3057\u307e\u3057\u305f\u3002<\/p>\n\n\n\n
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\u5730\u4e0a\u306b\u5b58\u5728\u3059\u308b\u7269\u8cea\u306e\u539f\u5b50\u6838\u306f\u7d20\u7c92\u5b50\u3067\u3042\u308b\u30a2\u30c3\u30d7\u30af\u30a9\u30fc\u30af (u)\u3001\u30c0\u30a6\u30f3\u30af\u30a9\u30fc\u30af (d) \u306e\u7d44\u307f\u5408\u308f\u305b\u3067\u6210\u308b\u6838\u5b50\u3067\u69cb\u6210\u3055\u308c\u307e\u3059 (\u967d\u5b50 = uud\u3001\u4e2d\u6027\u5b50 = udd)\u3002\u672c\u5b9f\u9a13\u7814\u7a76\u3067\u306f\u3001\u30b9\u30c8\u30ec\u30f3\u30b8\u30af\u30a9\u30fc\u30af\u3092 2 \u3064\u542b\u3080\u30d0\u30ea\u30aa\u30f3\u3067\u3042\u308b\u30b0\u30b6\u30a4\u7c92\u5b50 (ssd) \u3092\u539f\u5b50\u6838\u306b\u675f\u7e1b\u3055\u305b\u305f\u7279\u6b8a\u306a\u539f\u5b50\u6838\u30fb\u30b0\u30b6\u30a4\u30cf\u30a4\u30d1\u30fc\u6838\u3092\u9ad8\u30a8\u30cd\u30eb\u30ae\u30fc\u30d3\u30fc\u30e0\u3067\u4eba\u5de5\u7684\u306b\u751f\u6210\u3057\u307e\u3059\u3002\u305d\u3057\u3066\u3001\u305d\u306e\u8cea\u91cf\u3092\u7cbe\u5bc6\u306b\u6e2c\u5b9a\u3059\u308b\u3053\u3068\u3067\u3001\u30b0\u30b6\u30a4\u7c92\u5b50\u3068\u6838\u5b50\u306e\u9593\u306b\u50cd\u304f\u5f37\u3044\u76f8\u4e92\u4f5c\u7528 (\u039eN \u76f8\u4e92\u4f5c\u7528) \u306b\u95a2\u3059\u308b\u65b0\u305f\u306a\u77e5\u898b\u3092\u5f97\u308b\u3053\u3068\u3092\u76ee\u7684\u3068\u3057\u3066\u3044\u307e\u3059\u3002\u30b0\u30b6\u30a4\u30cf\u30a4\u30d1\u30fc\u6838\u306f\u5199\u771f\u4e7e\u677f\u3092\u7528\u3044\u305f\u5b9f\u9a13\u306b\u3088\u308a\u6570\u4f8b\u306e\u89b3\u6e2c\u4f8b\u304c\u3042\u308b\u306e\u307f\u3067\u3042\u308b\u3053\u3068\u304b\u3089\u3001\u039eN \u76f8\u4e92\u4f5c\u7528\u306e\u5f37\u3055\u3084\u30b9\u30d4\u30f3\u4f9d\u5b58\u6027\u7b49\u306e\u8a73\u7d30\u306a\u6027\u8cea\u306f\u660e\u3089\u304b\u306b\u3055\u308c\u3066\u3044\u307e\u305b\u3093\u3002J-PARC E70 \u306f\u3001\u30b0\u30b6\u30a4\u30cf\u30a4\u30d1\u30fc\u6838\u306e\u675f\u7e1b\u4e8b\u8c61\u3092 100 \u30a4\u30d9\u30f3\u30c8\u4ee5\u4e0a\u306e\u9ad8\u7d71\u8a08\u3067\u3001\u304b\u3064 2 MeV (\u534a\u5024\u5168\u5e45) \u3068\u3044\u3063\u305f\u9ad8\u30a8\u30cd\u30eb\u30ae\u30fc\u5206\u89e3\u80fd\u3067\u89b3\u6e2c\u3059\u308b\u3053\u3068\u76ee\u6307\u3057\u305f\u5b9f\u9a13\u7814\u7a76\u3067\u3059\u3002<\/p>\n\n\n\n
<\/p>\n\n\n\n
\u3053\u306e\u4e16\u754c\u6700\u9ad8\u611f\u5ea6\u3067\u306e\u30b0\u30b6\u30a4\u30cf\u30a4\u30d1\u30fc\u6838\u6e2c\u5b9a\u306b\u306f\u3001\u7279\u306b\u4ee5\u4e0b\u306e 3 \u3064\u306e\u5b9f\u9a13\u8981\u7d20\u304c\u30ab\u30ae\u3068\u306a\u308a\u307e\u3059\uff1a<\/p>\n\n\n\n
\u672c\u7814\u7a76\u305f\u306e\u3081\u306b 10 \u5e74\u4ee5\u4e0a\u306e\u5e74\u6708\u3092\u304b\u3051\u3066\u7814\u7a76\u958b\u767a\u3068\u6e96\u5099\u3092\u9032\u3081\u3001\u4eca\u5e74\u3088\u308a\u7269\u7406\u30c7\u30fc\u30bf\u306e\u53d6\u5f97\u3092\u306f\u3058\u3081\u307e\u3057\u305f\u304c\u3001\u8a08\u753b\u3057\u3066\u3044\u305f\u91cf\u306e\u30c7\u30fc\u30bf\u306e\u53d6\u5f97\u3092\u5b8c\u4e86\u3057\u307e\u3057\u305f\u3002\u3053\u308c\u304b\u3089\u672c\u683c\u7684\u306b\u30c7\u30fc\u30bf\u89e3\u6790\u3092\u884c\u3044\u30011\uff5e2 \u5e74\u306e\u3046\u3061\u306b\u306f\u7d50\u679c\u3092\u307e\u3068\u3081\u3066\u516c\u8868\u3067\u304d\u308c\u3070\u3068\u8003\u3048\u3066\u3044\u307e\u3059\u3002<\/p>\n\n\n\n
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Data acquisition for the Xi hypernuclear spectroscopy experiment (E70 experiment) conducted at the J-PARC Hadron Experimental Facility has been completed. The nuclei of matter existing on Earth are composed of nucleons, which are combinations of the elementary particles up quarks (u) and down quarks (d) (proton = uud, neutron = udd). In this experimental study, we artificially produce a special nucleus called a Xi hypernucleus by binding a Xi particle (ssd), a baryon containing two strange quarks, to an atomic nucleus using a high-energy beam. The aim is to gain new insights into the strong interaction between Xi particles and nucleons (\u039eN interaction) by precisely measuring its mass. As there are only a few observed cases of Xi hypernuclei using photographic emulsion experiments, detailed properties such as the strength and spin dependence of the \u039eN interaction have not been clarified. J-PARC E70 is an experimental study aimed at observing Xi hypernuclear binding events with high statistics of over 100 events and high energy resolution of 2 MeV (full width at half maximum). <\/p>\n\n\n\n
For this measurement of Xi-hypernuclei with the world's highest sensitivity, the following three experimental elements are key:<\/p>\n\n\n\n
For this research, we have spent over 10 years on research, development, and preparation. This year, we began acquiring physical data and have completed the collection of the planned amount of data. From now on, we will conduct full-scale data analysis, and we hope to publish the results within 1-2 years.
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