DIRAC status + K - and K + -atoms + -atoms ( ) Run 2011 Future magnet level scheme, Stark effect and energy splitting measurement 1 Leonid Nemenov 21. October 2011 I Status of + K -atoms 2 Run , statistics with low and medium background ( of all statistics). Point-like production of all particles. The e + e background was not subtracted. Q Q relative momentum in the K c.m.s. A. Benelli, V. Yazkov Coulomb pairs Atomic pairs non-Coulomb pairs II Status of - K + -atoms 3 Run , statistics with low and medium background ( of all statistics). Point-like production of all particles. The e + e background was not subtracted. A. Benelli, V. Yazkov Q relative momentum in the K c.m.s. Coulomb pairs Atomic pairs non-Coulomb pairs III. The status of - K + and + K atoms 4 A. Benelli, V. Yazkov Run , statistics with low and medium background ( of all statistics). Point-like production of all particles. The e + e background was not subtracted. Q relative momentum in the K c.m.s. Coulomb pairs Atomic pairs non-Coulomb pairs IV Status + -atoms 5 Run , statistics with low and medium background ( of all statistics). Point-like production of all particles. The e + e background was not subtracted. Coulomb pairs Atomic pairs non-Coulomb pairs A. Benelli, V. Yazkov Coulomb pairs Atomic pairs non-Coulomb pairs V Status of 2011 run 6 Neodymium magnetic piece=70x60x5mm 3 : Gap=60mm; BL=0.01Tm Time of delivery to CERN: before 4 May 2011 y z x 150mm 90mm 60mm Tokyo Metropolitan University & Kyoto University Simulation of long-lived A 2 observation V. Yazkov Without magnetWith magnet after Be target 7 Coulomb peak of + 8 Shift because of magnet degradation ! Shift of Q y (June-August) + data 9 Q x distribution (B x =0) 10 F. Takeutchi, V. Yazkov Shift of Q y (June-August) e + e data Pairs generated after magnet Pairs generated on Be target before magnet F. Takeutchi, V. Yazkov 12 Shift of Q y (June-August) e + e data without central peak 12 e + e generated on Be target before magnet F. Takeutchi, V. Yazkov Shift of Q y (August-September) e + e data without central peak 13 F. Takeutchi, V. Yazkov VI STATUS OF THE FUTURE MAGNET Halbach configuration NdBFe or SmCo 60 x 60 bore B = 0.89 T The magnets cost about $. The fabrication time is about 65 days. Y. Iwashita 14 flat Y. Iwashita By along z-axis 15 V. Brekhovskikh Current Magnet Holder 16 The New Magnet Holder Y. Iwashita 17 A 2 Energy Levels J. Schweizer (P. L. 2oo4) For Coulomb potential E depends on n only. CONCLUSION: one parameter (2a 0 +a 2 ) allows to calculate all ns-np values. VII ENERGY SPLITTING MEASUREMENT 18 Coulomb bound state and strong & electromagnetic perturbation DGBT *) formula & numerical values: A) Energy shift contributions: ______ *) Deser, Goldberger, Baumann, Thirring, PR 96 (1954) 774. B) Decay width: with Remark S-wave scattering lengths are amplitudes at threshold: em shiftstrong shift vacuum polarization 19 and A 2 level scheme and 2s 2p energy splitting n=1 n=2 n= E n (keV) 1s 1s 2s 2s Stark mixing J. Schacher 20 E 2s-2p Values for energy shifts and lifetimes of + atom [J. Schweizer, PL B587 (2004) 33] *) J. Schacher 21 CERN, Geneva - Monday 26, September, 2011 M. Pentia nHnH H 10 8 s 2 s Decay length A 2 in L.S. cm for =16.1 2p p p p p p 46.8 * 226 8p 69.3 * 335 A 2 lifetime, , in np states * - extrapolated values 22 L. Afanasev; O. Gorchakov (DIPGEN) Atomic pairs from A 2 long-lived states breakup in 2m Pt. Long-lived A 2 yield and quantum numbers 23 24 Impact on atomic beam by external magnetic field B lab and Lorentz factor ++ See: L. Nemenov, V. Ovsiannikov, Physics Letters B 514 (2001) 247. . relative distance between + and in A 2 system . laboratory magnetic field electric field in A 2 system Lamb shift measurement with external magnetic field L. Nemenov, V. Ovsiannikov [PL B514 (2oo1) 247] F strength of electric field in A 2 c.m.s. m must be 0 B L B lab in lab system CONCLUSION: the lifetimes for long-lived states can be calculated using only one parameter E 2s -E 2p. The lifetime of A 2 in electric field 25 A 2 * (2p-state) lifetime versus electric field Atom-field interaction: with J. Schacher 26 will change => [weak-field limit] H=0.4 T H=0.6 T H=0.8 T H=1.0 T H=1.2 T H=1.4 T H=1.6 T H=0.0 T =1 N A =330 40 H=0.1 T =1 N A =330 (1-0.7%) 27 V. Brekhovskikh Magnetic Field T 28 2p3p4p5p6p7p8p n,% 10 -11,s L,cm n eff 10 -11,s L eff,cm NaNa N a eff Magnetic Field 1.0 T = 40% p3p4p5p6p7p8p n,% 10 -11,s L,cm n eff 10 -11,s L eff,cm NaNa N a eff Magnetic Field 1.0 T = 100% p3p4p5p6p7p8p n,% 10 -11,s L,cm n eff 10 -11,s L eff,cm NaNa N a eff Magnetic Field 1.0 T = 160% CERN, Geneva - Monday 26, September, 2011 V. Brekhovskikh 29 Reserve: 30 External magnetic and electric fields Atoms in a beam are influenced by external magnetic field and the relativistic Lorentz factor. 31 L. Nemenov, V. Ovsiannikov (P. L. 2oo1) F strength of electric field in A 2 c.m.s. m must be 0 B L in lab. syst. CONCLUSION: the lifetimes for long-lived states can be calculated using only one parameter E 2s -E 2p. The lifetime of A 2 in electric field 32 mmmmmmmmmm m