Spring-8 Result y K M=1.54±0.01GeV T<25 MeV Gaussian significance 4.6o KK n 0+ n(p) d→KKnp >N Cuts:noφ→K+K no recoil p (yn only) p (yn only Missing mass for n 0 145151551.61.651.71.7518 PRL91,012002(2003 MMc(GeV/c2)
Spring-8 Result M = 1.540.01 GeV G < 25 MeV Gaussian significance 4.6s Q+ Q+ + d → K- K+ n p Cuts: no f→K+Kno recoil p (n only) Missing mass for n PRL 91, 012002 (2003)
CLASJLAB Results Yd口pk+k-n yponktK- T 35 40 30 30 25 25 g20 (nK)(Gev/c 15 10 15 1.6 18 19 2.2 24 M(Kn)[Gev/c1 M(nk)(GeV/c) M=1542±5Mev M=1555±10MeV [<21 Mev [<26 Mev 5.2σ 78σ Phys.Rev.Le9g1,(2003)252001 Phys.Rev.Le92,(2004)032001
M = 155510 MeV G < 26 MeV 7.8 s CLAS/JLAB Results Phys.Rev.Lett.91, (2003) 252001 M = 15425 MeV G< 21 MeV 5.2 s d p K+ K- n p n K+ K- p + Phys. Rev. Lett. 92, (2004) 032001
Many Experiments Confirm @+ Experiments Results Mass Width (Mev) (Mev) (=N3/√Nb) SPring8 1540105 G25 4.61 DIANA 15392“few g 8 4.4 CLAS 154225 FWhM= 21 5305 SAPHIR 154042 G<25 4.8 ITEP(N) 15335 G<20 6.7 HERMES 1526 2 2 G<13 5.60.5 KN elastic G< few Mev! One theory 1530 Mev G<15 MeV (CQsM) I=0S=+1JP=2+
Many Experiments Confirm Q+ Experiments Results Mass Width (MeV) (Mev) SPring8 DIANA CLAS SAPHIR ITEP (n) HERMES KN elastic 1540 10 5 G 25 4.6 1 1539 2 “few” G 8 4.4 1542 2 5 FWhM= 21 5.3 0.5 1540 4 2 G < 25 4.8 1533 5 G < 20 6.7 1526 2 2 G < 13 5.6 0.5 G < few MeV ! One theory (cQSM) 1530 MeV G<15 MeV I=0 S=+1 JP=½+ ( / ) s = N N s b
Many experiments with null results Noticeably(biased list CDF p+p Very high Energy HERA-B p+A sqrt(s)42 Gev BES Babar e++e collisions ALEPH DELPHI
Many Experiments with Null Results Noticeably (biased list) CDF p + p Very High Energy HERA-B p + A sqrt(s) 42 GeV BES BaBar e + + e- collisions ALEPH DELPHI
Possible t photo-Production reactions CLASJLAB LEPS/SPring-8 p K K K d /KK n Exclusive channels T K N Not Solid Physical Picture P K
Possible Q+ Photo-Production Reactions Q+ Q + CLAS/JLAB LEPS/SPring-8 Exclusive Channels ! Not Solid Physical Picture!