Search for a massless particle beyond the Standard Model in the Σ +→𝑝 + invisibledecay

M. Ablikima;M. N. Achasovd;3;P. Adlarson cc;O. Afedulidis c;X. C. Ai ch;R. Aliberti al;A. Amoroso bz;cb;Q. An bw;bi 1;Y. Bai bh;O. Bakina am;I. Balossino ae;Y. Ban aw;8;H. -R. Bao bo;V. Batozskaya a;au;K. Begzsuren ai;N. Berger al;M. Berlowskiau;M. Bertaniab;D. Bettoni ae;F. Bianchi bz;cb;E. Bianco bz;cb;A. Bortone bz;cb;I. Boyko am;R. A. Briere e;A. Brueggemann bt;H. Caicd;X. Cai a;bi;A. Calcaterra ab;G. F. Cao a;bo;N. Cao a;bo;S. A. Cetin bm;J. F. Chang a;bi;G. R. Che at;G. Chelkov am;2;C. Chen at;C. H. Chen i;Chao Chen bf;G. Chen a;H. S. Chen a;bo;H. Y. Chent;M. L. Chena;bi bo;S. J. Chen as;S. L. Chen av;S. M. Chen bl;T. Chen a;bo;X. R. Chen ah;bo;X. T. Chen a;bo;Y. B. Chen a;bi;Y. Q. Chen ak;Z. J. Chen y;9;Z. Y. Chen a;bo;S. K. Choi j;G. Cibinetto ae;F. Cossio cb;J. J. Cui ba;H. L. Dai a;bi;J. P. Dai cf;A. Dbeyssi r;R. E. de Boer c;D. Dedovich am;C. Q. Deng bx;Z. Y. Deng a;A. Denig al;I. Denysenko am;M. Destefanisbz;cb;F. De Mori bz;cb;B. Ding br;a;X. X. Ding aw;8;Y. Ding ak;Y. Ding aq;J. Dong a;bi;L. Y. Dong a;bo;M. Y. Donga;bi bo;X. Dong cd;M. C. Dua;S. X. Du ch;Z. H. Duan as;P. Egorov am;2;Y. H. Fan av;J. Fang a;bi;J. Fang bj;S. S. Fang a;bo;W. X. Fanga;Y. Fang a;Y. Q. Fang a;bi;R. Farinelli;L. Fava;F. Feldbauer c;G. Felici ab;C. Q. Feng bw;bi;J. H. Feng bj;Y. T. Feng bw;bi;M. Fritschc;C. D. Fu a;J. L. Fu bo;Y. W. Fu a;bo;H. Gao bo;X. B. Gao ar;Y. N. Gao aw;8;Yang Gao bw;bi;S. Garbolino cb;I. Garzia ae;af;L. Ge ch;P. T. Ge cd;Z. W. Ge as;C. Geng bj;E. M. Gersabeck bs;A. Gilman bu;K. Goetzen m;L. Gong aq;W. X. Gonga;bi;W. Gradlal;S. Gramigna ae;af;M. Grecobz;cb;M. H. Gua;bi;Y. T. Gu o;C. Y. Guan a;bo;Z. L. Guan v;A. Q. Guo ah;bo;L. B. Guo ar;M. J. Guoba;R. P. Guo az;Y. P. Guo l;7;A. Guskov am;2;J. Gutierrez aa;K. L. Han bo;T. T. Han a;X. Q. Hao s;F. A. Harris bq;K. K. He bf;K. L. He a;bo;F. H. Heinsius c;C. H. Heinz al;Y. K. Heng a;bi bo;C. Herold bk;T. Holtmann

2024-01-01