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ミュオニウム超微細構造 の精密測定実験 ー イントロダクションー K.Shimomura (KEK). Muonium Energy Level. Fine Structure explained by Dirac. Classic Lamb Shift QED Tomonaga , Shwinger , Feynman . Not included QED weak hadronic correction. . . .
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ミュオニウム超微細構造 の精密測定実験 ーイントロダクションー K.Shimomura (KEK)
Muonium Energy Level Fine Structure explained by Dirac Classic Lamb Shift QED Tomonaga, Shwinger, Feynman Not included QED weak hadronic correction
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Test of CPT and Lorentz Invariance (V. W. Hughs et al., Phys. Rev. Lett. 87, 111804 (2001). Effective Lagragean predicts sidereal time change of muonium frequency.
q ⇒ Why Muonium HFSmeasurement is so important? • g-2 E821(BNL) 0.5ppm 3s deviation • -measurement of the deviation of muon spin direction(ws) • and muon momentum direction(wc)wa∝(g-2)/2=am • -The ratio to proton NMR frequency is important! • mm/mpaccuracy from direct measurement 0.12ppm • W. Liu et al., Phys. Rev. Lett. 82, 711 (1999). aman independentprecisemuon mass measurement is required From g-2 strage ring From Muonium HFS
Muonium Hamiltonian • ImmuonspinJelectron spin • mmBmuon Bohr magneton meBelectron Bohr magneton • g’mgyromagnetic ratio of electron in bound muonim • gJgyromagnetic ratio of muon in bound muonim • Dnground state muonium hyperfine constant
Old Muonium Method Delay time gate shows more sharp resonance !
Results of Los Alamos Experiment • n12=1897539800(35)Hz (18ppb), n34=2565762965(43)Hz (17ppb) • Dn=4463302765(53)Hz (12ppb), mm/mp=3.18334513(39) (120ppb) Combine the pervious results • Dn=4463302776(51)Hz (12ppb), mm/mp=3.18334524(37) (120ppb) (93% Error comes from statistical error) Muon mass determination Where, gm=2(1+am) am=0.01165923(8.5) (gmerror 4ppb) meB/mp=1.521032202(15) (1ppb) mm/me=206.768277(24) (120ppb)
How to improve the accuracy of mm/mp? • Comparison between theoretical and experimental value of Dn where,recoil term 800kHz(120ppm) and so on are included. R∞=10973731.568639(91)m-1(0.09ppt) (Cs atomic beam interferometory) a-1=137.03599958(52) (3.8ppb) (from electron g-2) mm/me=206.7682670(55) (27ppb), mm/mp=3.183345396(94) (30ppb) This value is used for the determination of g-2.
Statics at Los Alamos Experiment • Beam intensitya few ×107/s • Beam structureQuasi DC • 4msON 10ms OFF • Therefore actual beam intensity107/s • 1 run 10s×120step • Total1270run (magnetic field scan 200run, Micro wavescan1070 run) • Total Muon 1013
Expectes Statics at J-PARC MUSE Beam Intensity @H Line1 ×108/s Beam structurePulsed TotalBeam Time 200 days Total Muon~2.0×1015 200times statics ! This is ideal ! Beam Intensity @D2 0.9×107/s @0.3MW(next few years) 3.0×107/s @1MW(goal) 50days run makes 15 times higher statics.
Summary Dn=4463302776(51)Hz (12ppb),mm/mp=3.18334524(37) (120ppb) ・old muonium method ←Pulsed muon beam is ideal ! ・Total muon1013statiscal error is dominant(93%) → If we will get100 times muon, one order improvement is possible ! ・Muonium is formed at Kr gas →Intense low energy (<4MeV)beam is requiered ! →only possible @J-PARC/MUSE!!