1 / 51

Muonium – Physics of a Most Fundamental Atom Klaus Jungmann

Muonium (M). Muonium – Physics of a Most Fundamental Atom Klaus Jungmann Kernfysisch Versneller Instituut & Rijksuniversiteit Groningen Simple Atomic System Atomic Theory Fundamental Constants Fundamental Symmetries Search for New Physics Atomic Physics at Accelerators

bayle
Télécharger la présentation

Muonium – Physics of a Most Fundamental Atom Klaus Jungmann

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Muonium (M) Muonium – Physics of a Most Fundamental Atom Klaus Jungmann Kernfysisch Versneller Instituut & Rijksuniversiteit Groningen Simple Atomic System Atomic Theory Fundamental Constants Fundamental Symmetries Search for New Physics Atomic Physics at Accelerators Precision Measurements … Condensed Matter Physics Chemistry Low energy Muon Beams

  2. Muonium (M) What is it ? • “Muonium is the bound state of a • positive Muon and an Electron” • “point-like” particles • no (severe) strong interaction effects • calculable to required accuracy What is it good for ? • test of electromagnetic bound state theory • fundamental constants • tests of fundamental symmetries • search for New Physics • tool for condensed matter research • ……

  3. hydrogen-like atom but no strong interaction

  4. Discovery of Muonium 1960 Hyperfine Structure addressed as an Important Quantity From: V. Telegdi, in: “A Festschrift for Vernon W. Hughes”, 1990 Past of Muonium (Ground State Hyperfine Structure) There was stimulating competition

  5. . . . Theorists are confident that muonium HFS Can be calculated to 10 Hz, if needed (Eides, Pachucki,…)  magnetic moment mm , a

  6. The worlds most intense quasi continuous muon source - the Los Alamos Meson Physics Facility

  7. Solenoid Sm m+ e- Gated Detector m+in MW-Resonator/Kr target Muonium Hyperfine Structure Yale - Heidelberg - Los Alamos pulsedbeamessential freq. scan B scan old Muonium

  8. Results from LAMPF Muonium HFS Experiment measured: • n12 = 1 897 539 800(35) Hz ( 18 ppb) • n34 = 2 565 762 965(43) Hz ( 17 ppb) from Breit-Rabi equation: n12 +n34 • Dnexp = 4 463 302 765(53) Hz ( 12 ppb) • Dntheo = 4 463 302 563(520)(34)(<100) Hz (<120 ppb) n12 -n34 • mm/mp = 3.183 345 24(37) (120 ppb) alternatively derived: • mm/me = 206.768 277(24) (120 ppb) • a-1 = 137.036 0047(4 8) ( 35 ppb)

  9. CODATA 2002 a-1= 137.035 99X X (1) a-1= 137.035 999 9 (5)

  10. muonium and hydrogen hfs → proton structure

  11. Lepton Magnetic Anomalies in CPT and Lorentz Non - Invariant Models | | - m m - 0 0 18 CPT tests K K = £ r 10 K m 0 K - - | g g | | a a | - + - + - - 3 12 e e e e = = × × £ × r 1.2 10 2 10 e g a avg avg ? ? Are they comparable - Which one is appropriate • often quoted: • K0- K0 mass difference (10-18) • e- - e+ g- factors (2* 10-12) • We need an interaction • with a finite strength! Use common ground, e.g. energies Þ generic CPT and Lorentz violating DIRAC equation 1 n μ μ μ μν μ μ ν ψ - - - - + + = (i γ D m a γ b γ γ H σ ic γ D id γ γ D ) 0 μ μ μ 5 μν μν μν 5 2 º ¶ - iD i qA m μ μ a , b break CPT a , b , c , d , H break Lorentz Invariance μ μ μ μ μν μν μν Leptons in External Magnetic Field - + l l l = - » - Δω ω ω 4b a a a 3 - + l l - | E E | Δω h spin up spin down a = » r l - 2 l m c E l spin up 57 Bluhm , Kostelecky, Russell, Phys. Rev. D ,3932 (1998) For g - 2 Experiments : - | a a | ω h = × c - + l l r l 2 a m c avg l Dehmelt, Mittleman,Van Dyck, Schwinberg, hep - ph/9906262 Þ - - 21 24 £ × £ × r 1.2 10 r 3.5 10 electron muon μ e : : CPT– Violation Lorentz Invariance Violation • What is best CPT test ? • New Ansatz (Kostelecky) • K0  10-18 GeV/c2 • n  10-30 GeV/c2 • p  10-24 GeV/c2 • e-  10-27 GeV/c2 • Future: • Anti hydrogen  10-18 GeV/c2 What about Second Generation Leptons?

  12. CPT and Lorentz Invariance from Muon Experiments Muonium: new interaction below 2* 10-23 GeV Muon g-2: new interaction below 4* 10-22 GeV (CERN) 15 times better expected from BNL V.W. Hughes et al., Phys.Rev. Lett. 87, 111804 (2001)

  13. Present Status of Muonium Ground State Hyperfine Structure • No Experimental Activities known at this time • Refinement of Theory going on • e.g. • Eides, Grotch, “Three-Loop Radiative-Recoil Corrections to Hyerfine Splitting in Muonium”, Phys.Rev.D67, 113003 (2003) and hep-ph/0412372 (2005) • Marciano, “Muonium Lifetime and Heavy Quark Decays”, hep-ph/0403071 (2004) • . . . • Exploitation of the Atom in Condensed Matter Science • e.g. • Ivanter et al. “On the anomalous muonium hyperfine structure in silicon” J.Phys.: Condens. Matter 15, 7419 (2003) • ….

  14. History of Muonium Ground State Hyperfine Splitting Measurements NEVIS CHICAGO-SREL LAMPF LAMPF latest experiment Quoted Uncertainty [kHz] Year

  15. Future Possibilities for Muonium Ground State Hyperfine Structure • LAMPF Experiment limited bySTATISTICS • more MUONS needed  factor > 100 over LAMPF – pulsed > 5*108m+/s below 28 MeV/c • new ACCELERATORS • J-PARC ? • Neutrino Factory ? • Eurisol ? • GSI ? • FNAL • ……..

  16. What other experiments besides the Ground State Hyperfine Structure are possible ?

  17. Gas Stop • Yields up to 100% foreign gas effects • Polarization up to 50% (B=0) • 100% (B>>1T) Kr, Ar m+ m++e-M • Beam Foil • Muonium in Vacuo keV energy • n=2 state populated • fast muonium m+ 50% m+e- 1% m+e-e- 0.01% m+ • SiO2 Powder • thermal Muonium in Vacuo M(2s) /M(1s) < 10-4 • Yields up to 12% • Polarization 39(9)% velocity 1.5 cm/ tm M m+ Methods of Muonium Production

  18. Completed Experiments on Muonium 1s-2s Interval • Pioneering effort at KEK • (Chu,Mills,Nagamine et al.) • Precision measurement at RAL • (Heidelberg – Oxford – Rutherford – Strathclyde – Siberia –Yale • Collaboration)

  19. m++ e-+ Ekin 0 -.25 Rm 2S 244 nm Energy 244 nm -Rm 1S m+ Detection m+ Laser Mirror m+e- Target Diagnostics m+in Muonium 1S-2S Experiment Heidelberg - Oxford - Rutherford - Sussex - Siberia - Yale

  20. The most intense pulsed muon source – ISIS at the Rutherford Appleton Laboratory

  21. m++ e-+ Ekin 0 -.25 Rm 2S 244 nm Energy 244 nm -Rm 1S m+ Detection m+ Laser Mirror m+e- Target Diagnostics m+in Muonium 1S-2S Experiment Heidelberg - Oxford - Rutherford - Sussex - Siberia - Yale

  22. Muonium 1s-2s At RAL 1987 -2000

  23. exp Dn 1s-2s = 2455 528 941.0(9.1)(3.7) MHz Dn 1s-2s = 2455 528 935.4(1.4) MHz mm+= 206.768 38 (17) me (0.8ppm) qm+= [ -1 -1.1 (2.1) 10-9 ] qe-(2.2 ppb) theo Results:

  24. Future Possibilities for Muonium 1s-2s Interval • No Precision Experiment Activities known at this time • Exploitation of Laser Spectroscopy to obtain • “Slow Muons” Condensed Matter Science • (K. Nagamine et al. @RAL) Y Matsuda et alJ. Phys. G: Nucl. Part. Phys.29, 2039 (2003)

  25. Future Possibilities for Muonium 1s-2s Interval • RAL Experiment limited bySTATISTICS • more MUONS needed • factor > 1000 over RAL – pulsed > 5*108m+/s below 28 MeV/c • would enable cw laser spectroscopy ! (precision !) • new ACCELERATORS • J-PARC ? • Neutrino Factory ? • Eurisol ? • GSI ? • . . . . .

  26. m g-2 hadronic contribution weak contribution New Physics QED QED mm, a, gm mm m+e- DnHFS, n=1 m+e- Dn1S-2S QED mm mm a QED corrections weak contribution mm QED corrections

  27. wa wammc wp = am = mm wa emB - wp mp Fundamental Constants of Interest to g-2 Theory: * need a for muon ! * hadronic and weak corrections *various experimental sources of a<better 100ppb>need constants at very moderate *a no concern for (g-2)meven with recent correctionsaccuracy Experiment: * wa and B (wp) measured in (g-2)m experiment <better 0.35 and 0.1 ppm> * c is a defined quantity <“infinite” accuracy> *mm (mm) is measured in muonium spectroscopy (hfs) <better 120 ppb> NEW 2000 *em is measured in muonium spectroscopy (1s -2s) <better 1.2 ppb> NEW 1999 *mp in water known >> probe shape dependence<< <better 26 ppb> *m3He to mp in water >> gas has no shape effect << <better 4.5 ppb> being improved

  28. Any New Effort to improve significantly on the Muon Magnetic Anomaly will need better constants ! Where should they come from, if not from Muonium Spectroscopy ? 

  29. Did first Search for Conversion Amato et al. Phys.Rev.Lett. 21, 1709 (1968) Predicted M-M Conversion 1957- Named System “Muonium” ? Muonium – Antimuonium Conversion up to Now

  30. The most intense continuos source of muons – the Cyclotron Facility at the Paul Scherrer Institut

  31. Present Activities concerning Muonium – Antimuonium Conversion • No Experimental Activities known at this time • Theory is proposing lots of models • e.g. • Clark, Love “Muonium-Antimuonium Oscillations and Massive Majorana Neutrinos”, hep-ph/0307264 (2003) • Gusso, Pires, Pires, Rodrigues da Silva “Minimal 3-3-1 Model, lepton Mixing and Muonium- Antimuonium Conversion”, hep-ph/0208062 (2002) • Cvetic,Dib, Kim, Kim, “Muonium-Antimuonium Conversion in models with heavy neutrinos”, hep-ph/0504126 (2005) • Applequist, Christensen, Piai, Schrock “ Flavour-Changing Processes in Extended Technicolor”, Phys. Rev.D70, 093919 (2004) • ….

  32. Future Possibilities for Muonium – Antimuonium Searches • PSI Experiment limited bySTATISTICS • more MUONS needed  factor > 1000 over PSI – pulsed > 1*109m+/s below 28 MeV/c • new ACCELERATORS • J-PARC ? • Neutrino Factory ? • Eurisol ? • GSI ? • FNAL • . . . . .

  33. P(M)  sin2 [const * (GMM/GF)*t]*exp[-lm*t] • Background  exp(- nlm*t) ; n-fold coincidence detection • For GMM << GF M gains over Background • P(M) / Background  t2 * exp[+(n-1)* lm*t] Old Muonium for Muonium-Antimuonium Conversion ?  Pulsed ACCELERATOR

  34. There is not only Muonium Spectroscopy waiting for a push by Intense Muon Beams

  35. Muon Physics Possibilities at Any High Power Proton Driver i.e.  4 MW Muon Experiments Possible at a CERN Neutrino Factory - Expected Improvements

  36. Muon Physics Possibilities at Any High Power Proton Driver i.e.  4 MW < < < < K Jungmann 18-Apr-2001

  37. J-PARC is one Possibility • There are others • as well: • Neutrino Factory ? • Muon Collider ? • GSI ? • ….

More Related