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Teilchenphysik – ohne Beschleuniger und Kosmologie

Teilchenphysik – ohne Beschleuniger und Kosmologie. 31.5.07 Sommersemester 2007. 2. CP-Verletzung. H.W. Wilschut. P. C. T. matter. anti-matter. time   t ime. mirror image. Time reversal violation can be measured at low energies.

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Teilchenphysik – ohne Beschleuniger und Kosmologie

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  1. Teilchenphysik – ohne Beschleunigerund Kosmologie 31.5.07 Sommersemester 2007

  2. 2. CP-Verletzung

  3. H.W. Wilschut P C T matter anti-matter time  time mirror image Time reversal violation can be measured at low energies 3. Symmetries and the World according to Escher identical to start start anti-particle particle e+ e-

  4. BABAR 2001

  5. + - + - 3. Prinzip: CP-Verletzung spin P - (P - known) elementary particle + EDM + T (CP big deal) - CP ↔ T S. Paul, TUM

  6. ILL: the EDM experiment

  7. 50 pT Final Sussex-RAL-ILL result use of 199Hg co-magnetometer d(199Hg) < 8.7 × 10-28ecm (C.A. Baker et al. PRL 97(2006) 131801) | dn | < 2.9 x 10-26ecm (90% CL)

  8. EDM: PSI F overall = 100

  9. The PNPI experiment EDM • Polarize neutrons || B0 while filling the bottle • Apply B(wt)  B0 to get neutron spin  to B0 • Wait for a time T (~100 s): spin precesses about B0 • Apply B(wt) to get neutron spin || to B0; if w wL  = (w -wL )T • Analyze polarization: P = P0 cos()

  10. Improvements Mainly performed by the group at PNPI (V. Lobashev et al.): official collaboration agreement with TUM • higher degree of polarization – triple polarizers: a = 0.75 • higher electric field E - new material (CERAN): E = 10 kV/cm • more neutrons N- FRM II + UCN source, more efficient neutron guides • longer storage time T - better coating, better stability of B0: T 150 s • Systematic errors: stable B0 (3fT!) - 3He magnetometer with SQIDs (W. Heil, Mainz), better shielding, polarization and analysis with the same arrangement

  11. Überblick zur die Sensitivität von Neutronexperimenten • EDM: Energy: E ~0.000 000 000 000 000 000 000 1eV = 10-22 eV • n-Ladung: Impuls: p/p ~ 10-11(Winkelauflösung von 1Å auf 10m) • Feinstrukturkonstante /~ 10-8(Messung von: nvn) • Quark-Mischung  Vud ~ 7 x10-4 • Lebensdauer / ~ 10-3 • Gravitation und QM g/g ~ 10-2

  12. EDM Strong CP problem • Axion als pseudoskalares Teilchen

  13. Axion limits 2007 Baeßler et al. Westphal, Baeßler, H.A. PVLAS arXiv:hep-ph/0703108 UCN other limits

  14. 2. Prinzip: Mischung der Quarks • -Zerfall: ~ GF2 • n-Zerfall:~ 0.95. GF2 = cos2C. GF2 • K-Zerfall: :~ 0.05. GF2 = sin2C. GF2 Quarkmischung ist Rotation im Flavour-Raum (Null-Summe) CKM-Matrix ist unitär!

  15. Unitarity Check: The Quark Mixing CKM Matrix Parametrization: 3 angles, and a phase A, ,  are real

  16. Unitarity Check II: PDG:  = 59°  13°,  = 24°  4°

  17. Unitarity Check II Vud= 1 - 2/2 • dsf From A. Buras, Munich

  18. Unitarity check Vub 0.00001% Vus 5% Mixing of quarks = rotation in flavor-space: Test in first row: |Vud|2 + |Vus|2 + |Vub|2 ≈ cos2θ + sin2θ + 0 < 1 ? : Cabibbo Vud 95%

  19. Situation 1995 - 2004

  20. The PDG feels it has the right to redefine anything it wants • 1994: • The “centimeters” on the ruler on p. 227 of the booklet • are 0.97 cm long, because: • The booklet were returned from the printer at 0.25 times • the speed of light • A theorist is in charge of the PDG • The PDG feels it has the right to redefine anything it wants • There is a general decline of standards • There was an international conspiracy • It was a congressionally mandated cost-saving measure • PDG gives you more cm/inch than anyone else Is there a general decline of standards?

  21. Vus • Kaon semileptonic decays • K+p0l+nl • K0Lp-l+nlsul+nl D = (2.12±0.08%), d = -2.0% for K+ and 0.5% for K0 • I+ = 0.1605 ± 0.0009, I0 = 0.1561 ± 0.0008 • G+ = (2.56 ± 0.033)10-15 MeV, G0=(4.937 ± 0.053)10-15 MeV • f(0) = 0.961 ± 0.008, f(0) = 0.963 ± 0.004  Vus = 0.2196 ± 0.0017exp ± 0.0018th = 0.2196 ± 0.0026 (PDG 2002)

  22. Some news in 2005: Vus b

  23. CKM unitarity summary • Phase of consolidation • Achievements: • New K results • New A result • Halving of the theoretical error in radiative corrections • Continue to measure lifetime and correlation coefficients until limited by theory • Lifetime • Formfactors

  24. Neutronlebensdauer • Methode: UCN in Flaschen • Präzision / ~ 10-3 ~ 99.99 % elastische Reflexion ~ 0.01% inelastische Reflexion in meV-Bereich ~0.001% Absorption 885.7 ± 0.7 sec  878.5 ± 0.8 sec TUM TUM: magnetische Speicherung: keine Verluste

  25. 2 values 878.5 ± 0.8 sec Serebrov et al. 885.7 ± 0.7 sec PDG 2005  = 2 x 10-6

  26. Neutrons and Big Bang Nucleo Synthesis • Problem 1s after Big Bang: • What does a gas of n and p, when the universe expands and the temperature drops? • Inputs: • neutron lifetime  • Cross sections • neutrino cross-sections   1/ • nuclear physics 0.1 – 1 MeV (measured!) • Outputs: H, D, He, Li • number of particle families N • density  of (ordinary) matter in universe

  27. In more detail (1+ 3gA2) • Weak reaction rate n + e+  p + e n + e  p + e • Hubble expansion rate • Equating gives freeze out temp. • Free neutron beta-decay Neutron lifetime PDG 2006 Serebrov et al. 2005 Yp=0.2463(6) Yp=0.2479(6) astro-ph/0408523 v2

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