Teilchenphysik

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Teilchenphysik ohne Beschleuniger und
Kosmologie

31.5.07 Sommersemester 2007
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2. CP-Verletzung
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3. Symmetries and the World according to Escher
H.W. Wilschut
identical to start
start
anti-particle particle e e-
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BABAR 2001
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3. Prinzip CP-Verletzung
spin
P
-
(P - known)
elementary particle

EDM

T
(CP big deal)
-
CP ? T
S. Paul, TUM
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ILL the EDM experiment
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Final Sussex-RAL-ILL result
use of 199Hg co-magnetometer d(199Hg) lt 8.7
10-28 ecm
(C.A. Baker et al. PRL 97(2006) 131801)
dn lt 2.9 x 10-26 ecm (90 CL)
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EDM PSI
F overall 100
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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(?)

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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

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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 x 10-4
• Lebensdauer ? ?/? 10-3
• Gravitation und QM ? g/g 10-2

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EDM Strong CP problem

• Axion als pseudoskalares Teilchen

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Axion limits 2007
Baeßler et al. Westphal, Baeßler, H.A.
PVLAS
arXivhep-ph/0703108
UCN
other limits
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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!
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Unitarity Check The Quark Mixing CKM Matrix
Parametrization 3 angles, and a phase
A, ?, ? are real
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Unitarity Check II

PDG ? 59 ? 13, ? 24 ? 4
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Unitarity Check II
Vud 1 - ??2/2

• dsf

From A. Buras, Munich
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Unitarity check
0.00001
Vub
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Vus

• Mixing of quarks
• rotation in flavor-space
• Test in first row
• Vud2 Vus2 Vub2
• cos2? sin2? 0 lt 1 ?
• ? Cabibbo

Vud
95
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Situation 1995 - 2004
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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?
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Vus

• Kaon semileptonic decays
• K?p0lnl
• K0L?p-lnl s?ulnl
• D (2.120.08), 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)
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Some news in 2005 Vus
b
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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

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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
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2 values 878.5 0.8 sec Serebrov et al. 885.7
0.7 sec PDG 2005
? 2 x 10-6
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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

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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