Hadronic EDMs from Dyson-Schwinger: Rho-Meson & Nucleon Mario - - PowerPoint PPT Presentation

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Hadronic EDMs from Dyson-Schwinger: Rho-Meson & Nucleon Mario - - PowerPoint PPT Presentation

Hadronic EDMs from Dyson-Schwinger: Rho-Meson & Nucleon Mario Pitschmann Institute of Atomic and Subatomic Physics, Vienna University of Technology January 22 nd , 2015 / ACFI Introduction Introduction Part A: The Theoretical Framework Part


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SLIDE 1

Hadronic EDMs from Dyson-Schwinger: Rho-Meson & Nucleon

Mario Pitschmann

Institute of Atomic and Subatomic Physics, Vienna University of Technology

January 22nd, 2015 / ACFI

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SLIDE 2

Introduction

Introduction Part A: The Theoretical Framework Part B: The ρ Meson Part C: The Nucleon

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SLIDE 3

Introduction: The Energy Scale & Effective EDM Operators for dim ≥ 4 at scale ∼ 1 GeV

Calculation of hadronic EDMs naturally splits into 2 parts

1

Calculation of Wilson coefficients by integrating out short distances

2

Switching from perturbative quark-gluon description to non-perturbative treatment – (much harder and larger uncertainties) Effective EDM Operators for dim ≥ 4 at scale ∼ 1 GeV L1GeV

M

= −i¯ Θ g2

s

32π2 Ga

µν ˜

Ga

µν

− i 2

  • q=u,d

dq ¯ qσµνγ5q Fµν − i 2 gs

  • q=u,d

˜ dq ¯ q 1 2λaσµνγ5q Ga

µν

+ i K Λ2 εij (¯ Qid)(¯ Qjγ5u) + · · ·

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SLIDE 4

Part A: The Theoretical Framework

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SLIDE 5
  • 1. Dyson-Schwinger Equations
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SLIDE 6

Dyson-Schwinger Equation

Non-perturbative continuum approach to any QFT A shift in the integration variable (ϕ(x) → ϕ(x) + λ(x)), does not change the path integral for suitable b.c., i.e.

  • D[ϕ] δ

δϕ f[ϕ] = 0 Application to the generating functional Z[J] yields

  • D[ϕ]
  • − δS

δϕ + J

  • e−S+
  • d4x Jϕ = 0

with the action S =

  • d4x L. This can be rewritten as
  • − δS

δϕ δ δJ

  • + J
  • Z[J] = 0
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SLIDE 7

Dyson-Schwinger Equation

In QCD the fermion propagator is obtained by derivation of

δS δ ¯ ψ(x) δ δ¯ η, − δ δη, δ δJµ

  • + η(x)
  • Z[η, ¯

η, J] = 0 with respect to η leading after several formal manipulations to the Gap Equation for the quark propagator SF(p)−1 = i/ p Z2 + mq(µ) Z4 + Z1

  • d4q

(2π)4 g2Dµν(k − p)γµ λi 2 SF(k)Γν(k, p)

= − −1 −1

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SLIDE 8

Dyson-Schwinger Equation

1

Gap equation contains the full vertex Γµ and full gluon propagator Dµν(k − p), each satisfies it’s own DSE

2

DSE for the full vertex Γµ contains the four-point vertex, which has it’s own DSE. . . = ⇒ DSE is an infinite tower of equations relating all correlation functions DSE are exact relations and are the quantum Euler-Lagrange equations for any QFT Perturbative Expansion yields standard perturbative QFT

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SLIDE 9
  • 2. Bethe-Salpeter Equations
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SLIDE 10

Bethe-Salpeter Equations

Bethe-Salpeter equation is the DSE describing a bound 2 body system Obtained by four derivatives of the generating functional and several formal manipulations Γ(k; P) =

  • d4q

(2π)4 K(q, k; P)SF

  • q + P

2

  • Γ(q; P)SF
  • q − P

2

  • Solutions for discrete set P2 yield mass spectra

=

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SLIDE 11

Rainbow-Ladder Truncation

A symmetry-preserving truncation of the infinite set of DSEs which respects relevant (global) symmetries of QCD is the rainbow-ladder truncation in combination with the impulse approximation

  • 1. In BSE kernel

K(p, p′; k, k′) → −Gℓ(q2)Dfree

µν (q)λa

2 γµ ⊗ λa 2 γν

  • 2. In gap equation

Z1g2Dµν(q)Γa

ν(k, p) → Gℓ(q2)Dfree µν (q)λa

2 γν R-LT is first term in systematic expansion of q¯ q scattering kernel K(p, p′; k, k′)

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SLIDE 12

Gluon Propagator

DSE and unquenched QCD lattice studies show that the Full gluon propagator Dab

µν(p) = δab Gℓ(p2)

p2

  • δµν − pµpν

p2

  • is IR finite, i.e.

lim

p2→0 Dab µν(p) = finite

  • the gluon has dynamically generated mass in the IR

EM Observables in the static limit (qµ → 0) probe gluon propagator for small transversed momenta = ⇒ Point-like vector ⊗ vector contact interaction g2Dab

µν(p) = δabδµν

4παIR m2

G

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SLIDE 13

Contact Interaction Model

This implies Non-renormalizable theory Introduce proper-time regularization

1

Λuv = 1/τuv cannot be removed but plays a dynamical role and sets the scale of all dimensioned quantities

2

Λir = 1/τir implements confinement by ensuring the absence of quark production tresholds

Scale mG, is set in agreement with observables In the static limit q2 → 0 results "indistinguishable" from any

  • ther however sophisticated DSE approach

For q2 M2

dressed deviations are expected from other

experimental values

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SLIDE 14

Part B:

1The ρ Meson

  • 1M. P

., C. Y. Seng, M. J. Ramsey-Musolf, C. D. Roberts, S. M. Schmidt and D. J. Wilson,

  • Phys. Rev. C 87 (2013) 015205
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SLIDE 15

The ρ Meson

"Per se" from an experimental point of view uninteresting Short lifetime (∼ 10−24 s) makes EDM measurements hard (or rather impossible) Simplest system possibly providing EDM and hence perfect prototype particle Results available in QCD sum rules and other techniques Profile

1

IG(JPC) = 1+(1−−)

2

m = 775.49 ± 0.34 MeV, Γ = 149.1 ± 0.8 MeV

3

Primary decay mode (∼ 100%): ρ → ππ

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SLIDE 16

The ρ-Meson in Impulse Approximation

Impulse Approximation

Γα Γβ Γµ

q k−+ k++ k−− p p′

Γ(u)

αµβ ∝

  • d4k

(2π)4 TrCD

  • Γρ(u)

β

S(k++)Γ(u)

µ S(k−+)Γρ(u) α

S(k−−)

  • EDM sources induce CP violating corrections to the

1

qγq vertex

2

Bethe-Salpeter amplitude

3

Propagator

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SLIDE 17

The Magnetic Moment

Results for M(0) in units e/(2mρ) DSE - CIM 2.11 DSE - RL RGI-improved 2.01 DSE - EF parametrisation 2.69 LF - CQM 2.14 LF - CQM 1.92 QCD sum rules 1.8 ± 0.3 point particle 2

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SLIDE 18

The Θ-Term

Only CP violating dimension 4 operator Leff = −i¯ Θ g2

s

32π2 Ga

µν ˜

Ga

µν

No suppression by heavy scale (strong CP problem) U(1)A anomaly allows to rotate it into complex mass for evaluation (effective propagator correction) DSE 0.7 × 10−3 e ¯ Θ/1 GeV QCD sum rules 4.4 × 10−3 e ¯ Θ/1 GeV

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SLIDE 19

The Θ-Term

Only CP violating dimension 4 operator Leff = −i¯ Θ g2

s

32π2 Ga

µν ˜

Ga

µν

No suppression by heavy scale (strong CP problem) U(1)A anomaly allows to rotate it into complex mass for evaluation (effective propagator correction) DSE 0.7 × 10−3 e ¯ Θ/1 GeV QCD sum rules 4.4 × 10−3 e ¯ Θ/1 GeV

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SLIDE 20

The Θ-Term

Only CP violating dimension 4 operator Leff = −i¯ Θ g2

s

32π2 Ga

µν ˜

Ga

µν

No suppression by heavy scale (strong CP problem) U(1)A anomaly allows to rotate it into complex mass for evaluation (effective propagator correction) DSE 0.7 × 10−3 e ¯ Θ/1 GeV QCD sum rules 4.4 × 10−3 e ¯ Θ/1 GeV

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SLIDE 21

The Θ-Term

Only CP violating dimension 4 operator Leff = −i¯ Θ g2

s

32π2 Ga

µν ˜

Ga

µν

No suppression by heavy scale (strong CP problem) U(1)A anomaly allows to rotate it into complex mass for evaluation (effective propagator correction) DSE 0.7 × 10−3 e ¯ Θ/1 GeV QCD sum rules 4.4 × 10−3 e ¯ Θ/1 GeV

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SLIDE 22

The Θ-Term

Only CP violating dimension 4 operator Leff = −i¯ Θ g2

s

32π2 Ga

µν ˜

Ga

µν

No suppression by heavy scale (strong CP problem) U(1)A anomaly allows to rotate it into complex mass for evaluation (effective propagator correction) DSE 0.7 × 10−3 e ¯ Θ/1 GeV QCD sum rules 4.4 × 10−3 e ¯ Θ/1 GeV

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SLIDE 23

The Θ-Term

Only CP violating dimension 4 operator Leff = −i¯ Θ g2

s

32π2 Ga

µν ˜

Ga

µν

No suppression by heavy scale (strong CP problem) U(1)A anomaly allows to rotate it into complex mass for evaluation (effective propagator correction) DSE 0.7 × 10−3 e ¯ Θ/1 GeV QCD sum rules 4.4 × 10−3 e ¯ Θ/1 GeV

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SLIDE 24

The Quark-EDM

The intrinsic EDM of a quark itself Leff = − i 2

  • q=u,d

dq ¯ qσµνγ5q Fµν Effective qγq vertex correction DSE - CIM 0.79 (du − dd) DSE 0.72 (du − dd) Bag Model 0.83 (du − dd) QCD sum rules 0.51 (du − dd) Non-relativistic quark model 1.00 (du − dd)

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SLIDE 25

The Chromo-EDM

The Intrinsic Chromo-EDM of a quark itself Leff = − i 2 gs

  • q=u,d

˜ dq ¯ q 1 2λaσµνγ5q Ga

µν

Effective qγq vertex correction DSE - qγq −0.07 e˜ d− − 0.20 e˜ d+ DSE - BSA −0.12 e˜ d− + 0.11 e˜ d+ DSE - Propagator 1.35 e˜ d− − 0.60 e˜ d+ DSE 1.16 e˜ d− − 0.69 e˜ d+ QCD sum rules −0.13 e˜ d−

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SLIDE 26

The Chromo-EDM

The Intrinsic Chromo-EDM of a quark itself Leff = − i 2 gs

  • q=u,d

˜ dq ¯ q 1 2λaσµνγ5q Ga

µν

Effective qγq vertex correction DSE - qγq −0.07 e˜ d− − 0.20 e˜ d+ DSE - BSA −0.12 e˜ d− + 0.11 e˜ d+ DSE - Propagator 1.35 e˜ d− − 0.60 e˜ d+ DSE 1.16 e˜ d− − 0.69 e˜ d+ QCD sum rules −0.13 e˜ d−

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SLIDE 27

The Chromo-EDM

The Intrinsic Chromo-EDM of a quark itself Leff = − i 2 gs

  • q=u,d

˜ dq ¯ q 1 2λaσµνγ5q Ga

µν

Effective qγq vertex correction DSE - qγq −0.07 e˜ d− − 0.20 e˜ d+ DSE - BSA −0.12 e˜ d− + 0.11 e˜ d+ DSE - Propagator 1.35 e˜ d− − 0.60 e˜ d+ DSE 1.16 e˜ d− − 0.69 e˜ d+ QCD sum rules −0.13 e˜ d−

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SLIDE 28

The Chromo-EDM

The Intrinsic Chromo-EDM of a quark itself Leff = − i 2 gs

  • q=u,d

˜ dq ¯ q 1 2λaσµνγ5q Ga

µν

Effective Bethe-Salpeter amplitude correction DSE - qγq −0.07 e˜ d− − 0.20 e˜ d+ DSE - BSA −0.12 e˜ d− + 0.11 e˜ d+ DSE - Propagator 1.35 e˜ d− − 0.60 e˜ d+ DSE 1.16 e˜ d− − 0.69 e˜ d+ QCD sum rules −0.13 e˜ d−

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SLIDE 29

The Chromo-EDM

The Intrinsic Chromo-EDM of a quark itself Leff = − i 2 gs

  • q=u,d

˜ dq ¯ q 1 2λaσµνγ5q Ga

µν

Effective Bethe-Salpeter amplitude correction DSE - qγq −0.07 e˜ d− − 0.20 e˜ d+ DSE - BSA −0.12 e˜ d− + 0.11 e˜ d+ DSE - Propagator 1.35 e˜ d− − 0.60 e˜ d+ DSE 1.16 e˜ d− − 0.69 e˜ d+ QCD sum rules −0.13 e˜ d−

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SLIDE 30

The Chromo-EDM

The Intrinsic Chromo-EDM of a quark itself Leff = − i 2 gs

  • q=u,d

˜ dq ¯ q 1 2λaσµνγ5q Ga

µν

Effective Bethe-Salpeter amplitude correction DSE - qγq −0.07 e˜ d− − 0.20 e˜ d+ DSE - BSA −0.12 e˜ d− + 0.11 e˜ d+ DSE - Propagator 1.35 e˜ d− − 0.60 e˜ d+ DSE 1.16 e˜ d− − 0.69 e˜ d+ QCD sum rules −0.13 e˜ d−

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SLIDE 31

The Chromo-EDM

The Intrinsic Chromo-EDM of a quark itself Leff = − i 2 gs

  • q=u,d

˜ dq ¯ q 1 2λaσµνγ5q Ga

µν

Effective Bethe-Salpeter amplitude correction DSE - qγq −0.07 e˜ d− − 0.20 e˜ d+ DSE - BSA −0.12 e˜ d− + 0.11 e˜ d+ DSE - Propagator 1.35 e˜ d− − 0.60 e˜ d+ DSE 1.16 e˜ d− − 0.69 e˜ d+ QCD sum rules −0.13 e˜ d−

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SLIDE 32

The Chromo-EDM

The Intrinsic Chromo-EDM of a quark itself Leff = − i 2 gs

  • q=u,d

˜ dq ¯ q 1 2λaσµνγ5q Ga

µν

Effective Bethe-Salpeter amplitude correction DSE - qγq −0.07 e˜ d− − 0.20 e˜ d+ DSE - BSA −0.12 e˜ d− + 0.11 e˜ d+ DSE - Propagator 1.35 e˜ d− − 0.60 e˜ d+ DSE 1.16 e˜ d− − 0.69 e˜ d+ QCD sum rules −0.13 e˜ d−

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SLIDE 33

The Chromo-EDM

The Intrinsic Chromo-EDM of a quark itself Leff = − i 2 gs

  • q=u,d

˜ dq ¯ q 1 2λaσµνγ5q Ga

µν

Effective Bethe-Salpeter amplitude correction DSE - qγq −0.07 e˜ d− − 0.20 e˜ d+ DSE - BSA −0.12 e˜ d− + 0.11 e˜ d+ DSE - Propagator 1.35 e˜ d− − 0.60 e˜ d+ DSE 1.16 e˜ d− − 0.69 e˜ d+ QCD sum rules −0.13 e˜ d−

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SLIDE 34

The Chromo-EDM

The Intrinsic Chromo-EDM of a quark itself Leff = − i 2 gs

  • q=u,d

˜ dq ¯ q 1 2λaσµνγ5q Ga

µν

Effective propagator correction DSE - qγq −0.07 e˜ d− − 0.20 e˜ d+ DSE - BSA −0.12 e˜ d− + 0.11 e˜ d+ DSE - Propagator 1.35 e˜ d− − 0.60 e˜ d+ DSE 1.16 e˜ d− − 0.69 e˜ d+ QCD sum rules −0.13 e˜ d−

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SLIDE 35

The Chromo-EDM

The Intrinsic Chromo-EDM of a quark itself Leff = − i 2 gs

  • q=u,d

˜ dq ¯ q 1 2λaσµνγ5q Ga

µν

Effective propagator correction DSE - qγq −0.07 e˜ d− − 0.20 e˜ d+ DSE - BSA −0.12 e˜ d− + 0.11 e˜ d+ DSE - Propagator 1.35 e˜ d− − 0.60 e˜ d+ DSE 1.16 e˜ d− − 0.69 e˜ d+ QCD sum rules −0.13 e˜ d−

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SLIDE 36

The Chromo-EDM

The Intrinsic Chromo-EDM of a quark itself Leff = − i 2 gs

  • q=u,d

˜ dq ¯ q 1 2λaσµνγ5q Ga

µν

Effective propagator correction DSE - qγq −0.07 e˜ d− − 0.20 e˜ d+ DSE - BSA −0.12 e˜ d− + 0.11 e˜ d+ DSE - Propagator 1.35 e˜ d− − 0.60 e˜ d+ DSE 1.16 e˜ d− − 0.69 e˜ d+ QCD sum rules −0.13 e˜ d−

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SLIDE 37

The Chromo-EDM

The Intrinsic Chromo-EDM of a quark itself Leff = − i 2 gs

  • q=u,d

˜ dq ¯ q 1 2λaσµνγ5q Ga

µν

Effective propagator correction DSE - qγq −0.07 e˜ d− − 0.20 e˜ d+ DSE - BSA −0.12 e˜ d− + 0.11 e˜ d+ DSE - Propagator 1.35 e˜ d− − 0.60 e˜ d+ DSE 1.16 e˜ d− − 0.69 e˜ d+ QCD sum rules −0.13 e˜ d−

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SLIDE 38

The Chromo-EDM

The Intrinsic Chromo-EDM of a quark itself Leff = − i 2 gs

  • q=u,d

˜ dq ¯ q 1 2λaσµνγ5q Ga

µν

Effective propagator correction DSE - qγq −0.07 e˜ d− − 0.20 e˜ d+ DSE - BSA −0.12 e˜ d− + 0.11 e˜ d+ DSE - Propagator 1.35 e˜ d− − 0.60 e˜ d+ DSE 1.16 e˜ d− − 0.69 e˜ d+ QCD sum rules −0.13 e˜ d−

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SLIDE 39

The Chromo-EDM

The Intrinsic Chromo-EDM of a quark itself Leff = − i 2 gs

  • q=u,d

˜ dq ¯ q 1 2λaσµνγ5q Ga

µν

Effective propagator correction DSE - qγq −0.07 e˜ d− − 0.20 e˜ d+ DSE - BSA −0.12 e˜ d− + 0.11 e˜ d+ DSE - Propagator 1.35 e˜ d− − 0.60 e˜ d+ DSE 1.16 e˜ d− − 0.69 e˜ d+ QCD sum rules −0.13 e˜ d−

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SLIDE 40

The Effective 4-Quark Operator

The effective 4-quark operator L = i K Λ2 εij (¯ Qid)(¯ Qjγ5u) with ¯ Qi =

  • ¯

u ¯ d

  • No results obtained in other methods yet

Effective qγq vertex correction DSE - qγq −1.00 × 10−5 KeνH/Λ2 DSE - BSA −9.11 × 10−7 KeνH/Λ2 DSE - Propagator −6.91 × 10−6 KeνH/Λ2 DSE −1.79 × 10−5 KeνH/Λ2

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SLIDE 41

The Effective 4-Quark Operator

The effective 4-quark operator L = i K Λ2 εij (¯ Qid)(¯ Qjγ5u) with ¯ Qi =

  • ¯

u ¯ d

  • No results obtained in other methods yet

Effective qγq vertex correction DSE - qγq −1.00 × 10−5 KeνH/Λ2 DSE - BSA −9.11 × 10−7 KeνH/Λ2 DSE - Propagator −6.91 × 10−6 KeνH/Λ2 DSE −1.79 × 10−5 KeνH/Λ2

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SLIDE 42

The Effective 4-Quark Operator

The effective 4-quark operator L = i K Λ2 εij (¯ Qid)(¯ Qjγ5u) with ¯ Qi =

  • ¯

u ¯ d

  • No results obtained in other methods yet

Effective Bethe-Salpeter amplitude correction DSE - qγq −1.00 × 10−5 KeνH/Λ2 DSE - BSA −9.11 × 10−7 KeνH/Λ2 DSE - Propagator −6.91 × 10−6 KeνH/Λ2 DSE −1.79 × 10−5 KeνH/Λ2

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SLIDE 43

The Effective 4-Quark Operator

The effective 4-quark operator L = i K Λ2 εij (¯ Qid)(¯ Qjγ5u) with ¯ Qi =

  • ¯

u ¯ d

  • No results obtained in other methods yet

Effective Bethe-Salpeter amplitude correction DSE - qγq −1.00 × 10−5 KeνH/Λ2 DSE - BSA −9.11 × 10−7 KeνH/Λ2 DSE - Propagator −6.91 × 10−6 KeνH/Λ2 DSE −1.79 × 10−5 KeνH/Λ2

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SLIDE 44

The Effective 4-Quark Operator

The effective 4-quark operator L = i K Λ2 εij (¯ Qid)(¯ Qjγ5u) with ¯ Qi =

  • ¯

u ¯ d

  • No results obtained in other methods yet

Effective Bethe-Salpeter amplitude correction DSE - qγq −1.00 × 10−5 KeνH/Λ2 DSE - BSA −9.11 × 10−7 KeνH/Λ2 DSE - Propagator −6.91 × 10−6 KeνH/Λ2 DSE −1.79 × 10−5 KeνH/Λ2

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SLIDE 45

The Effective 4-Quark Operator

The effective 4-quark operator L = i K Λ2 εij (¯ Qid)(¯ Qjγ5u) with ¯ Qi =

  • ¯

u ¯ d

  • No results obtained in other methods yet

Effective Bethe-Salpeter amplitude correction DSE - qγq −1.00 × 10−5 KeνH/Λ2 DSE - BSA −9.11 × 10−7 KeνH/Λ2 DSE - Propagator −6.91 × 10−6 KeνH/Λ2 DSE −1.79 × 10−5 KeνH/Λ2

slide-46
SLIDE 46

The Effective 4-Quark Operator

The effective 4-quark operator L = i K Λ2 εij (¯ Qid)(¯ Qjγ5u) with ¯ Qi =

  • ¯

u ¯ d

  • No results obtained in other methods yet

Effective propagator correction DSE - qγq −1.00 × 10−5 KeνH/Λ2 DSE - BSA −9.11 × 10−7 KeνH/Λ2 DSE - Propagator −6.91 × 10−6 KeνH/Λ2 DSE −1.79 × 10−5 KeνH/Λ2

slide-47
SLIDE 47

The Effective 4-Quark Operator

The effective 4-quark operator L = i K Λ2 εij (¯ Qid)(¯ Qjγ5u) with ¯ Qi =

  • ¯

u ¯ d

  • No results obtained in other methods yet

Effective propagator correction DSE - qγq −1.00 × 10−5 KeνH/Λ2 DSE - BSA −9.11 × 10−7 KeνH/Λ2 DSE - Propagator −6.91 × 10−6 KeνH/Λ2 DSE −1.79 × 10−5 KeνH/Λ2

slide-48
SLIDE 48

The Effective 4-Quark Operator

The effective 4-quark operator L = i K Λ2 εij (¯ Qid)(¯ Qjγ5u) with ¯ Qi =

  • ¯

u ¯ d

  • No results obtained in other methods yet

Effective propagator correction DSE - qγq −1.00 × 10−5 KeνH/Λ2 DSE - BSA −9.11 × 10−7 KeνH/Λ2 DSE - Propagator −6.91 × 10−6 KeνH/Λ2 DSE −1.79 × 10−5 KeνH/Λ2

slide-49
SLIDE 49

Part C:

2The Nucleon

  • 2M. P

., C. Y. Seng, C. D. Roberts and S. M. Schmidt, arXiv:1411.2052 [nucl-th].

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SLIDE 50

Introduction

Nucleon’s tensor charge P(p, σ)|¯ qσµνq|P(p, σ) = δTq ¯ u(p, σ)σµνu(p, σ) (q = u, d, . . .) δTq = 1

−1

dx hq

1T(x) =

1 dx [hq

1T(x) − h¯ q 1T(x)]

h1T . . . transversity distribution measures the light-front number-density of quarks with transverse polarisation parallel to that of the proton minus that of quarks with antiparallel polarisation

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SLIDE 51

Introduction

Relation tensor charge to EDM dp ¯ u(p, σ)σµνγ5u(p, σ) =

  • q=u,d

dq P(p, σ)|¯ qσµνγ5q|P(p, σ) = 1 2 εµναβ

  • q=u,d

dq P(p, σ)|¯ qσαβq|P(p, σ) = 1 2 εµναβ ¯ u(p, σ)σαβu(p, σ)

  • q=u,d

dq δTq = ¯ u(p, σ)σµνγ5u(p, σ)

  • q=u,d

dq δTq Proton EDM: dp = du δTu + dd δTd Neutron EDM: dn = du δTd + dd δTu

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SLIDE 52

The Quark-EDM

ℓ + p p p −ℓ

0+

ℓ + p

Λ+(p)S(−p)

  • d4ℓ

(2π)4 S(u)(ℓ + p)σµνS(u)(ℓ + p)∆0+(−ℓ)S(p)Λ+(p) = N δTd Λ+(p)σµνΛ+(p) S(p) = s(p) 1D

  • s(p) = 0.8810
  • Λ+(p) =

1 2mN (−iγ · p + mN)

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SLIDE 53

The Quark-EDM

ℓ + p p p −ℓ

1+

ℓ + p α β

Λ+(p)Ai

α(−p)

  • d4ℓ

(2π)4 S(q)(ℓ + p)σµνS(q)(ℓ + p)∆1+

αβ(−ℓ)Ai β(p)Λ+(p)

= N δTq Λ+(p)σµνΛ+(p) Ai

µ(p) = ai 1(p) γ5γµ + ai 2(p) γ5ˆ

  • ˆ

p2 = −1, i = +, 0

  • a+

1 = −0.380, a+ 2 = −0.065, a0 1 = 0.270, a0 2 = 0.046

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SLIDE 54

The Quark-EDM

ℓ + p p p −ℓ ℓ + p

0+ 0+

Λ+(p)S(−p)

  • d4ℓ

(2π)4 ∆0+

αα′(ℓ + p)Λµν∆0+ β′β(ℓ + p)S(q)(−ℓ)S(p)Λ+(p)

= 0 "A spinless particle cannot have a vectorial/tensorial structure of any kind!"

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SLIDE 55

The Quark-EDM

ℓ + p p p −ℓ ℓ + p α β

1+ 1+

Λ+Ai

α(−p)

  • d4ℓ

(2π)4 ∆1+

αα′(ℓ + p)Λα′µνβ′∆1+ β′β(ℓ + p)S(q)(−ℓ)Ai β(p)Λ+

= N δTq Λ+(p)σµνΛ+(p) Ai

µ(p) = ai 1(p) γ5γµ + ai 2(p) γ5ˆ

  • ˆ

p2 = −1, i = +, 0

  • a+

1 = −0.380, a+ 2 = −0.065, a0 1 = 0.270, a0 2 = 0.046

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SLIDE 56

The Quark-EDM

ℓ + p p p −ℓ ℓ + p α

1+ 0+

Λ+(p)S(−p)

  • d4ℓ

(2π)4 ∆0+(ℓ + p)Λµνα∆1+

αβ(ℓ + p)S(u)(−ℓ)A0 β(p)Λ+(p)

= N δTd Λ+(p)σµνΛ+(p) S(p) = s(p) 1D

  • s(p) = 0.8810
  • A0

µ(p) = a0 1(p) γ5γµ + a0 2(p) γ5ˆ

  • a0

1 = 0.270, a0 2 = 0.046

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SLIDE 57

The Quark-EDM

ℓ + p p p −ℓ ℓ + p α

0+ 1+

Λ+(p)A0

α(−p)

  • d4ℓ

(2π)4 ∆1+

αβ(ℓ + p)Λβµν∆0+(ℓ + p)S(u)(−ℓ)S(p)Λ+(p)

= N δTd Λ+(p)σµνΛ+(p) S(p) = s(p) 1D

  • s(p) = 0.8810
  • A0

µ(p) = a0 1(p) γ5γµ + a0 2(p) γ5ˆ

  • a0

1 = 0.270, a0 2 = 0.046

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SLIDE 58

The Quark-EDM

The intrinsic EDM of a quark itself Leff = − i 2

  • q=u,d

dq ¯ qσµνγ5q Fµν ζH ≈ M δTu δTd Diagram 1 0.581 Diagram 2 −0.018 −0.036 Diagram 3 Diagram 4 0.292 0.059 Diagram 5+6 −0.164 −0.164 Total Result 0.691 −0.141 dp|ζH≈M = 0.69(10) du − 0.14(2) dd dn|ζH≈M = −0.14(2) du + 0.69(10) dd

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SLIDE 59

The Quark-EDM

Significance of δTu αIR reduced by 20% leads to δTu reduced by 20% with δTd practically unchanged = ⇒ δTu is a direct probe of DCSB Significance of δTd δTd is non-zero only due to Axial-vector correlations = ⇒ δTd is a probe of Axial-vector correlations δTu is increased by 11% in the absence of Axial-vector correlations = ⇒ δTu is suppressed by Axial-vector correlations

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SLIDE 60

The Quark-EDM

Flavour separation of the proton’s tensor charge

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SLIDE 61

Conclusion

Continuum approach to any QFT Originates at the QCD current quark/gluon level, i.e. all

  • perators are "implemented" at that level

"Rigid structure" – few model parameters Has been shown to work well in the CP conserving sector

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SLIDE 62

Collaboration

The results, expounded in this talk, were obtained in Collaboration with Craig D. Roberts – ANL Michael J. Ramsey-Musolf – UMass Amherst Chien-Yeah Seng – UMass Amherst

Thank You For Your Attention!