From http luchins comwhatweretheythinkinginsanelybadscience Stephen L Olsen Seoul

From: http: //luchins. com/what-were-they-thinking/insanely-bad-science/ Stephen L. Olsen Seoul National University

2008 Nobel Physics Prize Kobayashi & Maskawa explained CP violation within the framework of the Standard Model, but required that the Model be extended to three doublets of quarks. These predicted, hypothetical new quarks have recently appeared in physics experiments. As late as 2001, the two particle detectors Ba. Bar at Stanford, USA and Belle at Tsukuba, Japan, both detected CP violations independently of each other. The results were exactly as Kobayashi and Maskawa had predicted almost three decades earlier. Kobayashi Maskawa

Thread of this talk CP violation What is it? three doublets of quarks Why three? B mesons (Ba. Bar & Belle experiments) Why B mesons? Stockholm

CP Violations Differences between matter & antimatter e- e+ P+ hydrogen P- Different? antihydrogen

Dilemma Laws of physics are very symmetric between matter & antimatter Nature is very asymmetric between matter & antimatter no antimatter here

Big-Bang Cosmology Then: a“no-hair” Universe matter = antimatter Now: people Only mass, electric charge & angular momentum no antipeople

Where are the antipeople? Need to study violations of “CP” symmetry

P = Parity (x, y, z) (-x, -y, -z) Field (& rules) of football are parity symmetric Rules of baseball are not parity symmetric

Parity violation in physics -a nano history-

Parity Conservation in QM 1924: Atomic Wave functions are either even or odd. Laporte rule: dipole transitions connect even odd (& not even or odd) Otto Laporte 1902 -1971 1927: Nature is Parity symmetric Laporte rule = Parity conservation Eugene Wigner 1902 -1995

q-t puzzle 1949 1947 cloud chamber q+ photographic emulsion p+ q+ t + p +p +p - p +p 0 mt = 970 me (495 Me. V) mq ≈ mp/2 R. Brown et al. , Nature 163, 47, 82 (1949) G. D. Rochester & C. C. Butler, Nature 160, 855 (1947) p has odd parity: P(p) = -p P(q ) =+ q q has even parity same mass, same lifetime, opposite P P(t ) = -t t has odd parity

Lee and Yang Phys Rev 104, 254 (1956) T. D. Lee C. N. Yang The q+ and t+ are the same particle, and its decays violate Parity. (now known as the K+ meson)

Parity violation discovered _ Co 60 Ni 60 e- n more electrons are emitted opposite to the nuclear spin direction than along it J J WU, Chien Shiung 1912 -97 C. S. Wu et al. , Phys. Rev. 105 (1957), 1415. The mirror image, where electrons are emitted parallel to the spin, doesn’t occur in Nature.

1957 Nobel Prize Yang, Chen-Ning Lee, Tsung-Dao WU, Chien Shiung

P-violations in m- & m+ decay _ decays: e- emission opposite to spin direction preferred m- e -n n m + e o i v is C e + m d e t la tor ra pe o e l rtic a le c i t Par ip Ant R L Garwin, L M Lederman and M Weinrich Phys. Rev. 105, 1415 (1957 ) _ decays: e+ emission parallel to spin direction preferred m+ e +n n

C x P in m decay at e d Mirrored antimatter case does occur in Nature ol d Vi o Vi e lat CP m P C e sy r t e m m s i y e+ K O + m “charg conjug e ate” mirror

CP in the neutral K meson system “Flavor” eigenstates CP (Hamiltonian? ) eigenstates d s s d Short life-time KShort Vio Long life-time KLong P C e lat

Christenson-Cronin-Fitch-Turlay Experiment (1964) Search for long-lived neutral kaon p+p- p+ Long-lived neutral Kaons p-

Long-lived neutral K p+p(~2 parts in 103) Small CP violation (2 x 10 -3) is seen J. H. Christenson et al. , PRL 13 (1964), 138.

1980 Nobel Prize No prizes for Christenson or Turlay

Incorporating CPV into QM

It‘s difficult to generate matter-antimatter differences in QM antiparticle process Particle process amplitude = A A’ Ti m e(t rev -t) ersa l amplitude = CPT theorem: A & A‘ |A|2 2 |A’| = can differ at most by a complex phase

In QM, processes are |Amp|2 A +f |A CP -f |2 = |A’|2 CP A’ Still no matter-antimatter difference (even though there is a CPV phase)

Phase measurement needs interference (a second way to get to the same final state) A A +X +f X |A + X|2 = | A’ +X|2 CP -f CP A’ + X A’ Still no matter-antimatter difference (even though there is a CPV phase & an interfering process)

X must have a “common” phase same phase for particle & antiparticle A +f -f X CP d A+X |A + X|2 = | A’ +X|2 Finally an matter-antimatter difference CP A’ + X A’

Matter-antimatter differences in QM • Amplitude needs a complex phase – Opposite sign for matter & antimatter • Need an interfering amplitude – Competing process same final state • Interfering amplitude needs a “common” phase – Same sign for matter & antimatter

Incorporating a CPV phase into the Standard Model for Particle Physics

Quark mixing In the late 1973, there were 3 known quarks (u, d, s): K & M were convinced of the existence of a 4 th quark: the hypothesized “charmed” quark (c): q= 2/3 q=-1/3 c

In the Weak Int. the s & d quarks mix Mass (& flavor) eigenstates Weak-interaction eigenstates quark-flavor-mixing Matrix

The weak interaction quark doublets The CPV KLong p+p- decays correspond to this transition d KLong s b d p u d + p u Incorporate CP violation by making b complex?

: Not so simple a 2 x 2 matrix has 8 parameters unitarity: 4 quark fields: # of irreducible parameters: 4 conditions 3 free phases 1 Cabibbo 1 st proposed quark flavor-mixing in 1963 Phys. Rev. Lett. 10: 531 -533, 1963 Cabibbo angle N. Cabibbo

A complex phase cannot be included in a 4 -quark mixing matrix

Kobayashi-Maskawa paper (1973) Prog. of Theor. Phys. Vol. 49 Feb. 2, 1973 3 “Euler” angles 1 CP-violating phase 4 irreducible parameters

a 3 x 3 matrix has 18 parameters unitarity: 6 quark fields: # of irreducible parameters: 9 conditions 5 free phases 4

Why were K&M so sure of the c quark? In 1972, they both were in Nagoya, where Kiyoshi Niu was on the Expt’l Particle Physics Faculty 2 mm K. Niu 2009: m. D=1. 87 Ge. V, m. Lc=2. 29 Ge. V

History November 1974: Charmed (4 th) quark “discovered” @ Brookhaven & SLAC J/ = c c 1976 Nobel prize M(e+e-) pp J/ + X; J/ e+e. Phys. Rev. Lett. 33: 1404 -1406, 1974. Ecm(e+e-) e+e- hadrons Phys. Rev. Lett. 33: 1406 -1408, 1974 Sam Ting Burt Richter Kiyoshi Niu

More History November 1977: Bottom (5 th) quark discovered @ Fermilab = bb February 1995: Top (5 th) quark discovered @ Fermilab ℓ+ n _ _ pp t t X _ bc Phys. Rev. Lett. 39: 252 -255, 1977. CDF: Phys. Rev. Lett. 74: 2626 -2631, 1995 D 0: Phys. Rev. Lett. 74: 2632 -2637, 1995

Now there are 6 quarks as required by Kobayashi-Maskawa CPV mechanism Mass (& flavor) eigenstates Weak-interaction eigenstates Related by a 3 x 3 mixing matrix

Cabibbo-Kobayashi-Maskawa 6 -quark mixing matrix CKM hierarchy V≈1 Nearly (but not exactly) diagonal d s b u V≈0. 2 c V≈0. 04 t V≈0. 004

The KM phases are in the corners 3 1 t Vtd b d W+ Vub u W+

The experimental challenge * Vub b u W+ Measure a complex phase for b u Vtd t d W+ or in t d or, even better, both

Use B mesons i. e. mesons containing the b- (5 th) quark B 0 = d b 0 0 B /B B 0 = b d similar to 0 0 K /K

Why B mesons? _ 1) B 0 mixing is strong 2 ps B 0 N(B) + N(B) B 0 ---------------- _ _ N(B) – N(B) B 0 ei mt _ B 0 _ _ B 0 If you start with a B 0, it changes to a B 0 (& vice versa) with a ¼-period (1/ m≈2 ps) that is comparable to the B 0 lifetime (≈1. 5 ps) 2) b quarks are sensitive to CPV phases - they probe the corners of the CKM matrix

Sanda, Bigi , Carter technique for 1 _ Interfere B f. CP with B B f. CP Vcb J/ B 0 KS + mixing provides the “common” phase V*td B 0 ei mt Vtb J/ Vcb 2 V* td sin 2 1 B 0 Vtb td V*td KS Phys. Rev. D 23: 1567, 1981 Nucl. Phys. B 193: 85, 1981

What do we measure? B 0 & _0 B in an quan “entang tum state led” e “Flavor-tag” _ decay (B 0 or B 0 ? ) J/ e Asymmetric energies KS z B-B B+B (tags) sin 2 1 more B tags t=0 t t z/cbg This is for f. CP=+1; for f. CP=-1, the asymmetry is opposite f. CP

The Belle experiment at KEK

KEK laboratory in Japan Tsukuba Mountain KEKB Collider KEK laboratory

elle A magnetic spectrometer based on a huge superconducting solenoid

_ Find B 0(B 0? ) J/ KS decays p p - 0 0 B (B ? ) J/ Ks event m m- Tracking chamber only

Check the other tracks to see if the accompanying meson is a B 0 or a B 0 ? ? ? ?

Check the other tracks to see if the The K in the remaining tracks means 0 the 0 accompanying meson is a B or a B 0 other meson is (probably) a B (not a B 0) p _ p B D K& _ B D K+ are dominant decay chains p K- p- p-

Determine the time sequence of the 2 decays Silicon micro-vertex detector k c + tra m m- tra Resolution ≈ 150 mm tracks from accompanying B meson B J/ KS decay occurs before the tag decay ck

Belle 2007 Make the plot & fit it PRL 98: 003802 (2007) B 0 tag ~7500 evts _ B 0 tag _ ~6500 evts B 0 tag CP=-1 CP=+1 sin 2 1 = 0. 681 ± 0. 025 1 = 21. 50 ± 1. 00 Similar results from the Ba. Bar experiment at SLAC Ba. Bar, Phys. Rev. Lett. 87: 091801, 2001 Belle, Phys. Rev. Lett. 87: 091802, 2001

Compare with KM theory constraints from other processes Ba. Bar & Belle measurement 1 | _ Vtd Vcb Nobel committee: “The results were exactly as Kobayashi and Maskawa had predicted…”

Stockholm, December 2008

Does this explain why there are no antipeople? No! Not by more than 10 orders-of-magnitude! CP violation in the early Universe due to the KM mechanism is too small

There must be another CPV source -one that’s not in the current Standard Model for particle physics- §Fourth generation of quarks? §New particles -- SUSY? , Technicolor? . . . §CPV in the neutrino sector? §…

How to find New Physics particles: 1) Produce them in very high energy collisions Go to CERN Join a 2000 physicist team LHC world’s highest energies Look for signs of NP particles buried in very complex events

Or 2) Look for effects of Virtual NP particles in B decays virtual heavy NP particles could contribute to the loop For example B K : V*tb , Y , x so-called “Penguin processes” Vts (also: h’, K K-, etc. )

Sensitivity structure of the CKM matrix suppresses FCNC SM b s “penguin” b * Vtb Vts s t * V V tb ts HSM Mt 2 0. 04 Mt 2 heaviest of all known particles X= heavy NP particle b g g X s |g |2 HNP MX 2 1 Te. V, the largest mass accessible at LHC For “generic” NP (i. e. g 1): MX ≈ 5 Mt can produce deviations from SM predictions O (1)

example: sin 2 f 1 with SM b s penguins Vtb& Vts: no SM CPV phases in B 0 Kf , … V* tb Vts Interfere with V* , h’, K+K- + Same measurement that we did for -except now the decays are much less common- , h’, K+K- B 0 K 0 … 1 td Vtd* B 0 J/ _ B 0 K , 1 SM prediction: sin 2 f 1 = sin 2 f 1 from B J/y K 0 penguin Any difference new particles in the loop

sin 2 f 1 from penguin ~200 evts ~200 evts 0 B → 0 K ~1400 evts sin 2 f 1 penguin =0. 67± 0. 22 & 0 K h’ ~2000 evts sin 2 f 1 penguin =0. 64± 0. 11 very near SM expectation of: sin 2 f 1 = 0. 681 ± 0. 025 Belle, PRL 98 : 003802 (2007) Ba. Bar, PRD 79, 052003 (2009) Ba. Bar, ar. Xiv 0808. 0700

No evidence yet for new heavy particles n SM Different penguin decay modes sin 2 1 No O(1) NP effects: MX > 1 Te. V ( g 2) tatio c e exp

What’s next? Super-KEKB & Belle II 50 x increase in data Make these error regions as small as this one sin 2 1 Sensitivity for new physics increases to 10 Te. V or higher well be e LHC h of th c a e r e h t yond

Summary 1927: Nature is Left-Right symmetric Parity is an important symmetry Laporte Wigner 1956: Weak Interactions violate Parity, but CP symmetry is preserved Yang Lee 1964: CP is violated too Cronin Fitch 1973: CP violations require 6 quark flavors Kobayashi Maskawa 20? ? : New non-SM CPV source found in B decays? ?