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Oklo: case study in extracting information on fundamental - - PowerPoint PPT Presentation

Oklo: case study in extracting information on fundamental interactions from CN processes Edward Davis edward.davis@ku.edu.kw Kuwait University ACFI Workshop: Tests of Time-Reversal in Nuclear and Hadronic Processes (November 6 to 8,


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Oklo: case study in extracting information on fundamental interactions from CN processes

Edward Davis edward.davis@ku.edu.kw

Kuwait University ACFI Workshop: “Tests of Time-Reversal in Nuclear and Hadronic Processes” (November 6 to 8, 2014)

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SLIDE 2

Outline

Introduction What is Oklo? Why is Oklo interesting? Interpretation of Oklo Unified treatment Earlier estimate of sensitivity to quark mass Interpretation of Oklo within many-body chiral EFT model Ingredients of model Sensitivity to quark mass: approximations & results Comparisons with epithermal TRNI studies Analysis in epithermal regime Final result Final thoughts

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What is Oklo?

◮ Site (in Gabon) of natural fission reactors

◮ active ∼ 2 × 109 years ago ◮ characteristic distribution of isotopes (= natural abundances)

◮ SLOW neutron + HEAVY nucleus = SENSITIVE receiver

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SLIDE 4

Why is Oklo interesting?

◮ Bounds on shifts in resonances =

⇒ Most restrictive bound on ∆α = αthen − αnow

z ∆α/αnow ˙ α/α (yr−1) Atomic clock (Al+/Hg+) (−1.6 ± 2.3) × 10−17 Oklo (n + 149Sm) 0.16 (−1.0 → 0.7) × 10−8 (−4 → 5) × 10−18 Meteorites 0.43 (−0.25 ± 1.6) × 10−6 Quasar absorption (MM) 0.2 − 4.2 (−5.7 ± 1.1) × 10−6 Cosmic µwave background 103 −0.013 → 0.015 Big-bang nucleosynthesis 109 < 6 × 10−2 Adapted from ProgTheorPhys.126.993. [Oklo result: ModPhysLettA.27.1250232]

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SLIDE 5

Why is Oklo interesting?

◮ Bounds on shifts in resonances =

⇒ Most restrictive bound on ∆α = αthen − αnow

z ∆α/αnow ˙ α/α (yr−1) Atomic clock (Al+/Hg+) (−1.6 ± 2.3) × 10−17 Oklo (n + 149Sm) 0.16 (−1.0 → 0.7) × 10−8 (−4 → 5) × 10−18 Meteorites 0.43 (−0.25 ± 1.6) × 10−6 Quasar absorption (MM) 0.2 − 4.2 (−5.7 ± 1.1) × 10−6 Cosmic µwave background 103 −0.013 → 0.015 Big-bang nucleosynthesis 109 < 6 × 10−2 Adapted from ProgTheorPhys.126.993. [Oklo result: ModPhysLettA.27.1250232] ◮ Issue: influence of QCD parameters, specifically changes in light

quark mass mq ≡ 1

2 (mu + md)?

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SLIDE 6

Interpretation of Oklo: unified treatment

[IntJModPhysE.23.1430007] ◮ ∆Er ≡ Er(Oklo) − Er(now) = kq

∆Xq Xq + kα ∆α α

  • Xq =

mq ΛQCD

  • ◮ kq independent of mass number A!

◮ Conjecture based on study of p-shell nuclei/schematic CN model

[PhysRevC.79.034302/PhysRevD.67.063513]

◮ kq susceptible to nuclear matter analysis ◮ Order of magnitude estimate for kq?

Model dependent

kq ≃ +10 MeV

(Walecka model)

kq ≃ −40 MeV

(Chiral model)

(kα ≃ −1 MeV [NuclPhysB.480.37])

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SLIDE 7

Interpretation of Oklo: unified treatment

[IntJModPhysE.23.1430007] ◮ ∆Er ≡ Er(Oklo) − Er(now) = kq

∆Xq Xq + kα ∆α α

  • Xq =

mq ΛQCD

  • ◮ kq independent of mass number A!

◮ Conjecture based on study of p-shell nuclei/schematic CN model

[PhysRevC.79.034302/PhysRevD.67.063513]

◮ kq susceptible to nuclear matter analysis ◮ Order of magnitude estimate for kq?

Model dependent

kq ≃ +10 MeV

(Walecka model)

kq ≃ −40 MeV

(Chiral model)

(kα ≃ −1 MeV [NuclPhysB.480.37])

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SLIDE 8

Interpretation of Oklo: Walecka model estimate of kq

[PhysRevC.79.034302] ◮ Shift δEr (due to δXq) CN

− − − →

model

Depth U0 of nuclear mean-field δEr U0 ≈ − δmN mN + 2δr0 r0 + δU0 U0

  • Independent of A

(R = r0A

1 3 )

◮ Walecka model estimate of U0-term implies (Ignore δr0)

δEr U0 ≈ 7.50δmS mS −5.50δmV mV −δmN mN ≡

  • 7.50K q

S − 5.50K q V − K q N

δXq Xq

◮ Uncertain microscopic interpretation of scalar S and vector V

bosons − → No first principles calculation of K q

S , K q V ◮ In PhysRevC.79.34302,

K q

S , K q V chosen such that kq ∼ +10 MeV

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SLIDE 9

Interpretation of Oklo: Walecka model estimate of kq

[PhysRevC.79.034302] ◮ Shift δEr (due to δXq) CN

− − − →

model

Depth U0 of nuclear mean-field δEr U0 ≈ − δmN mN + 2δr0 r0 + δU0 U0

  • Independent of A

(R = r0A

1 3 )

◮ Walecka model estimate of U0-term implies (Ignore δr0)

δEr U0 ≈ 7.50δmS mS −5.50δmV mV −δmN mN ≡

  • 7.50K q

S − 5.50K q V − K q N

δXq Xq

◮ Uncertain microscopic interpretation of scalar S and vector V

bosons − → No first principles calculation of K q

S , K q V ◮ In PhysRevC.79.34302,

K q

S , K q V chosen such that kq ∼ +10 MeV

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SLIDE 10

Interpretation of Oklo: Walecka model estimate of kq

[PhysRevC.79.034302] ◮ Shift δEr (due to δXq) CN

− − − →

model

Depth U0 of nuclear mean-field δEr U0 ≈ − δmN mN + 2δr0 r0 + δU0 U0

  • Independent of A

(R = r0A

1 3 )

◮ Walecka model estimate of U0-term implies (Ignore δr0)

δEr U0 ≈ 7.50δmS mS −5.50δmV mV −δmN mN ≡

  • 7.50K q

S − 5.50K q V − K q N

δXq Xq

◮ Uncertain microscopic interpretation of scalar S and vector V

bosons − → No first principles calculation of K q

S , K q V ◮ In PhysRevC.79.34302,

K q

S , K q V chosen such that kq ∼ +10 MeV

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SLIDE 11

Interpretation of Oklo within many-body chiral EFT model

◮ Plausible paradigm relating U0 to QCD?

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SLIDE 12

Interpretation of Oklo within many-body chiral EFT model

◮ Plausible paradigm relating U0 to QCD?

“M¨ unchen” model Ingredients Nuclear property Large scalar & vector self-energies Spin-orbit interaction Chiral πN∆-dynamics + Pauli-blocking Binding & saturation

NuclPhysA.750.259 NuclPhysA.770.1

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SLIDE 13

Interpretation of Oklo within many-body chiral EFT model

◮ Plausible paradigm relating U0 to QCD?

“M¨ unchen” model

◮ Calculation of U for symmetric nuclear matter

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SLIDE 14

Interpretation of Oklo within many-body chiral EFT model

◮ Plausible paradigm relating U0 to QCD?

“M¨ unchen” model

◮ Calculation of U for symmetric nuclear matter

Long range interactions

In-medium χPT to 3 loops

(1 & 2 π exchange, 1 & 2 virtual ∆ excitation)

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SLIDE 15

Interpretation of Oklo within many-body chiral EFT model

◮ Plausible paradigm relating U0 to QCD?

“M¨ unchen” model

◮ Calculation of U for symmetric nuclear matter

Long range interactions

In-medium χPT to 3 loops

(1 & 2 π exchange, 1 & 2 virtual ∆ excitation)

∆(1232) degree of freedom

Appropriate (∆ − N mass ≃ kFermi) Ensures model phenomenologically satisfactory

NuclPhysA.750.259

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SLIDE 16

Interpretation of Oklo within many-body chiral EFT model

◮ Plausible paradigm relating U0 to QCD?

“M¨ unchen” model

◮ Calculation of U for symmetric nuclear matter

Long range interactions

In-medium χPT to 3 loops

(1 & 2 π exchange, 1 & 2 virtual ∆ excitation)

∆(1232) degree of freedom

Appropriate (∆ − N mass ≃ kFermi) Ensures model phenomenologically satisfactory

Short range interactions

2 contact-terms Strengths fitted directly to nuclear matter properties

NuclPhysA.750.259

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Sensitivity to quark mass: approximations & results

Long & intermediate range interaction terms → ˜ U0 =

i

U0i

˜ U0 mN = π 4 MπgA 2πFπ 4 (9 + 6u2) tan−1 u − 9u

  • Twice iterated 1π-exchange (2 medium insertions)

+ . . . (u =

kF Mπ )

◮ In terms of hadronic parameters P (i.e. Mπ, Fπ, gA, mN & ∆)

δ ˜ U0 U0 = 1 U0 δ ˜ U0 δmq δmq =

  • P,i

U0i U0 P U0i δU0i δP

  • =K P

U0i

mq P δP δmq

  • =K q

P

  • δmq

mq

◮ Discard all but P = mπ term: K q

Mπ ≈ 1 2 ≫ other K q P’s

  • Berengut et al. (2013)

◮ Result: δ ˜

U0 U0 = −0.28δmq mq = ⇒ kq ∼ 10 MeV (!)

Same as PhysRevC.79.034302 but with controlled approximations

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SLIDE 18

Sensitivity to quark mass: approximations & results

Long & intermediate range interaction terms → ˜ U0 =

i

U0i

˜ U0 mN = π 4 MπgA 2πFπ 4 (9 + 6u2) tan−1 u − 9u

  • Twice iterated 1π-exchange (2 medium insertions)

+ . . . (u =

kF Mπ )

◮ In terms of hadronic parameters P (i.e. Mπ, Fπ, gA, mN & ∆)

δ ˜ U0 U0 = 1 U0 δ ˜ U0 δmq δmq =

  • P,i

U0i U0 P U0i δU0i δP

  • =K P

U0i

mq P δP δmq

  • =K q

P

  • δmq

mq

◮ Discard all but P = mπ term: K q

Mπ ≈ 1 2 ≫ other K q P’s

  • Berengut et al. (2013)

◮ Result: δ ˜

U0 U0 = −0.28δmq mq = ⇒ kq ∼ 10 MeV (!)

Same as PhysRevC.79.034302 but with controlled approximations

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SLIDE 19

Sensitivity to quark mass: approximations & results

Long & intermediate range interaction terms → ˜ U0 =

i

U0i

˜ U0 mN = π 4 MπgA 2πFπ 4 (9 + 6u2) tan−1 u − 9u

  • Twice iterated 1π-exchange (2 medium insertions)

+ . . . (u =

kF Mπ )

◮ In terms of hadronic parameters P (i.e. Mπ, Fπ, gA, mN & ∆)

δ ˜ U0 U0 = 1 U0 δ ˜ U0 δmq δmq =

  • P,i

U0i U0 P U0i δU0i δP

  • =K P

U0i

mq P δP δmq

  • =K q

P

  • δmq

mq

◮ Discard all but P = mπ term: K q

Mπ ≈ 1 2 ≫ other K q P’s

  • Berengut et al. (2013)

◮ Result: δ ˜

U0 U0 = −0.28δmq mq = ⇒ kq ∼ 10 MeV (!)

Same as PhysRevC.79.034302 but with controlled approximations

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SLIDE 20

Sensitivity to quark mass: approximations & results

Long & intermediate range interaction terms → ˜ U0 =

i

U0i

˜ U0 mN = π 4 MπgA 2πFπ 4 (9 + 6u2) tan−1 u − 9u

  • Twice iterated 1π-exchange (2 medium insertions)

+ . . . (u =

kF Mπ )

◮ In terms of hadronic parameters P (i.e. Mπ, Fπ, gA, mN & ∆)

δ ˜ U0 U0 = 1 U0 δ ˜ U0 δmq δmq =

  • P,i

U0i U0 P U0i δU0i δP

  • =K P

U0i

mq P δP δmq

  • =K q

P

  • δmq

mq

◮ Discard all but P = mπ term: K q

Mπ ≈ 1 2 ≫ other K q P’s

  • Berengut et al. (2013)

◮ Result: δ ˜

U0 U0 = −0.28δmq mq = ⇒ kq ∼ 10 MeV (!)

Same as PhysRevC.79.034302 but with controlled approximations

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SLIDE 21

Sensitivity to quark mass: approximations & results

2-body contact interaction (of strength B3)

◮ Source of largest term in U0!

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SLIDE 22

Sensitivity to quark mass: approximations & results

2-body contact interaction (of strength B3)

◮ Source of largest term in U0! ◮ Contributes to part of U0 linear in density ρ

3π 2mN

mN B3 + 15

16π2

gA 2πFπ 4 m2

NMπ

  • ρ→0

− − − → V (1S0)

low−k(0,0)+V (3S1) low−k(0,0)

ρ

[Vlow−k : Bogner, Kuo, Schwenk (2003)]

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SLIDE 23

Sensitivity to quark mass: approximations & results

2-body contact interaction (of strength B3)

◮ Source of largest term in U0! ◮ Contributes to part of U0 linear in density ρ

3π 2mN

mN B3 + 15

16π2

gA 2πFπ 4 m2

NMπ

  • ρ→0

− − − → V (1S0)

low−k(0,0)+V (3S1) low−k(0,0)

ρ

[Vlow−k : Bogner, Kuo, Schwenk (2003)]

◮ Working assumption: mq-dependence of Vlow−k negligible

K q

B3 = 0.52K q Mπ

= ⇒ δU0B3 U0 = +1.1δmq mq = ⇒ kq ≃ −40 MeV

Less controlled but still plausible?

(More details: DOI 10.1007/s00601-014-0909-0)

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SLIDE 24

Comparisons with epithermal TRNI studies

◮ Oklo (in summary):

Reactor data

Reactor

− − − − →

model

∆Er bound

“CN”

− − − →

model

δU0

χEFT

− − − →

model

δmq

◮ Epithermal TRNI:

Reaction data

Reaction

− − − − − →

model

s| VPT|p

  • =Vsp

bound

CN

− − − →

model

RMS Vsp

  • Average over p’s

?

− − − →

◮ All not well with Random Matrix Theory (RMT)?

◮ “Anomalous fluctuations of s-wave reduced neutron widths of 192,194Pt

resonances” PhysRevLett.105.072502

◮ “Neutron resonance data exclude Random Matrix Theory” FortschrPhys.61.80 ◮ “Uncertainties in the analysis of neutron resonance data” arxiv:1209.2439

by Shriner, Weidenm¨ uller and Mitchell

Abstract ends with “. . . our results confirm the earlier conclusion that the NDE disagrees significantly from RMT predictions”.

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SLIDE 25

Comparisons with epithermal TRNI studies

◮ Oklo (in summary):

Reactor data

Reactor

− − − − →

model

∆Er bound

“CN”

− − − →

model

δU0

χEFT

− − − →

model

δmq

◮ Epithermal TRNI:

Reaction data

Reaction

− − − − − →

model

s| VPT|p

  • =Vsp

bound

CN

− − − →

model

RMS Vsp

  • Average over p’s

?

− − − →

◮ All not well with Random Matrix Theory (RMT)?

◮ “Anomalous fluctuations of s-wave reduced neutron widths of 192,194Pt

resonances” PhysRevLett.105.072502

◮ “Neutron resonance data exclude Random Matrix Theory” FortschrPhys.61.80 ◮ “Uncertainties in the analysis of neutron resonance data” arxiv:1209.2439

by Shriner, Weidenm¨ uller and Mitchell

Abstract ends with “. . . our results confirm the earlier conclusion that the NDE disagrees significantly from RMT predictions”.

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SLIDE 26

Comparisons with epithermal TRNI studies

◮ Oklo (in summary):

Reactor data

Reactor

− − − − →

model

∆Er bound

“CN”

− − − →

model

δU0

χEFT

− − − →

model

δmq

◮ Epithermal TRNI:

Reaction data

Reaction

− − − − − →

model

s| VPT|p

  • =Vsp

bound

CN

− − − →

model

RMS Vsp

  • Average over p’s

?

− − − →

◮ All not well with Random Matrix Theory (RMT)?

◮ “Anomalous fluctuations of s-wave reduced neutron widths of 192,194Pt

resonances” PhysRevLett.105.072502

◮ “Neutron resonance data exclude Random Matrix Theory” FortschrPhys.61.80 ◮ “Uncertainties in the analysis of neutron resonance data” arxiv:1209.2439

by Shriner, Weidenm¨ uller and Mitchell

Abstract ends with “. . . our results confirm the earlier conclusion that the NDE disagrees significantly from RMT predictions”.

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SLIDE 27

Analysis in epithermal regime

Reaction data

2-level

− − − − →

model

Vsp and Ep (Already know Es’s) ◮ Invoke Eigenstate Thermalization Hypothesis

  • Nature.452.854

? ← → Chaotic |ψ

Eigenstate expectation values “almost do not fluctuate at all between eigenstates that are close in energy” Consequence: for any weights wα in small energy window ∆E

  • α

wαψα| O|ψα = 1 N∆E

  • α

ψα| O|ψα = Oµcan

◮ Introduce fig leaf average

(Weight ws ∝ 1 (Ep − Es)2 maybe)

σ2

p =

  • s

wsVpsVsp

  • Average over s

ET-like

− − − − − − →

hypothesis

1 NPsC

  • s

VpsVsp ≈ 1 NPsC p| V 2

|p NPsC: number of principle s-wave components of V|p

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SLIDE 28

Analysis in epithermal regime

Reaction data

2-level

− − − − →

model

Vsp and Ep (Already know Es’s) ◮ Invoke Eigenstate Thermalization Hypothesis

  • Nature.452.854

? ← → Chaotic |ψ

Eigenstate expectation values “almost do not fluctuate at all between eigenstates that are close in energy” Consequence: for any weights wα in small energy window ∆E

  • α

wαψα| O|ψα = 1 N∆E

  • α

ψα| O|ψα = Oµcan

◮ Introduce fig leaf average

(Weight ws ∝ 1 (Ep − Es)2 maybe)

σ2

p =

  • s

wsVpsVsp

  • Average over s

ET-like

− − − − − − →

hypothesis

1 NPsC

  • s

VpsVsp ≈ 1 NPsC p| V 2

|p NPsC: number of principle s-wave components of V|p

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SLIDE 29

Analysis in epithermal regime

Reaction data

2-level

− − − − →

model

Vsp and Ep (Already know Es’s) ◮ Invoke Eigenstate Thermalization Hypothesis

  • Nature.452.854

? ← → Chaotic |ψ

Eigenstate expectation values “almost do not fluctuate at all between eigenstates that are close in energy” Consequence: for any weights wα in small energy window ∆E

  • α

wαψα| O|ψα = 1 N∆E

  • α

ψα| O|ψα = Oµcan

◮ Introduce fig leaf average

(Weight ws ∝ 1 (Ep − Es)2 maybe)

σ2

p =

  • s

wsVpsVsp

  • Average over s

ET-like

− − − − − − →

hypothesis

1 NPsC

  • s

VpsVsp ≈ 1 NPsC p| V 2

|p NPsC: number of principle s-wave components of V|p

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SLIDE 30

Analysis in epithermal regime: final result

◮ Use ETH on σ2 p!

σ2

p ≈

1 NPsC V 2

µcan ≈

1 NPsC V 2

can Canonical ensemble averages calculable within chiral model for nuclear matter! ◮ Discard fig leaf of average (Weighting such that σp ≈ |Vsp|)

|Vsp| ≈ 1 √NPsC V 2

  • 1

2 can

Parallels with PhysRevLett.70.4051 ◮ Issues:

◮ Order of magnitude of N

− 1

2

PsC?

∼ 10−3 or ∼ 1?

◮ Validity of ET-like hypothesis?

(V 2

sp’s all much the same?) ◮ Choice of

V?

(→ Final thoughts) Shell model studies of issue 1? Address issue 2 with EGOE(1+2)-π or tractable many-body system

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SLIDE 31

Analysis in epithermal regime: final result

◮ Use ETH on σ2 p!

σ2

p ≈

1 NPsC V 2

µcan ≈

1 NPsC V 2

can Canonical ensemble averages calculable within chiral model for nuclear matter! ◮ Discard fig leaf of average (Weighting such that σp ≈ |Vsp|)

|Vsp| ≈ 1 √NPsC V 2

  • 1

2 can

Parallels with PhysRevLett.70.4051 ◮ Issues:

◮ Order of magnitude of N

− 1

2

PsC?

∼ 10−3 or ∼ 1?

◮ Validity of ET-like hypothesis?

(V 2

sp’s all much the same?) ◮ Choice of

V?

(→ Final thoughts) Shell model studies of issue 1? Address issue 2 with EGOE(1+2)-π or tractable many-body system

slide-32
SLIDE 32

Analysis in epithermal regime: final result

◮ Use ETH on σ2 p!

σ2

p ≈

1 NPsC V 2

µcan ≈

1 NPsC V 2

can Canonical ensemble averages calculable within chiral model for nuclear matter! ◮ Discard fig leaf of average (Weighting such that σp ≈ |Vsp|)

|Vsp| ≈ 1 √NPsC V 2

  • 1

2 can

Parallels with PhysRevLett.70.4051 ◮ Issues:

◮ Order of magnitude of N

− 1

2

PsC?

∼ 10−3 or ∼ 1?

◮ Validity of ET-like hypothesis?

(V 2

sp’s all much the same?) ◮ Choice of

V?

(→ Final thoughts) Shell model studies of issue 1? Address issue 2 with EGOE(1+2)-π or tractable many-body system

slide-33
SLIDE 33

Final thoughts

“[I]s it possible to interpret the neutron data in terms of the elementary weak interaction and mesonic couplings? The problem is usually decomposed into two fairly independent parts. In a first step, the effective parity-violating nucleon-nucleon interaction is calculated from the elementary weak interaction by taking into account the nuclear medium surrounding the two interacting nucleons. In a second step, this effective interaction is propagated into the huge shell-model spaces typical for compound-nucleus states at neutron threshold ... it is possible to determine the rms matrix element v and the spreading width ... The spreading width is found to lie in the expected range of 10−6 eV.” (RevModPhys.71.445) Since the 1980’s, most PV calculations have been expressed in terms of the DDH parameters. More recently EFT descriptions, both with and without explicit pion degrees of freedom, have been adopted to ensure consistency between PC and PV interactions and currents. Finally, instead of using the Lagrangian directly, hybrid calculations use a potential derived from the EFT Lagrangian combined with models for the PC interactions. ... we attempt to create a dictionary, to the extent possible ... There are some inherent uncertainties involved, particularly when cutoffs and subtraction points in one scheme are not compatible with another, so some of these translations cannot be considered exact and should be interpreted carefully. (ProgPartNuclPhys.72.1)

Thank you for your attention

slide-34
SLIDE 34

Final thoughts

“[I]s it possible to interpret the neutron data in terms of the elementary weak interaction and mesonic couplings? The problem is usually decomposed into two fairly independent parts. In a first step, the effective parity-violating nucleon-nucleon interaction is calculated from the elementary weak interaction by taking into account the nuclear medium surrounding the two interacting nucleons. In a second step, this effective interaction is propagated into the huge shell-model spaces typical for compound-nucleus states at neutron threshold ... it is possible to determine the rms matrix element v and the spreading width ... The spreading width is found to lie in the expected range of 10−6 eV.” (RevModPhys.71.445) Since the 1980’s, most PV calculations have been expressed in terms of the DDH parameters. More recently EFT descriptions, both with and without explicit pion degrees of freedom, have been adopted to ensure consistency between PC and PV interactions and currents. Finally, instead of using the Lagrangian directly, hybrid calculations use a potential derived from the EFT Lagrangian combined with models for the PC interactions. ... we attempt to create a dictionary, to the extent possible ... There are some inherent uncertainties involved, particularly when cutoffs and subtraction points in one scheme are not compatible with another, so some of these translations cannot be considered exact and should be interpreted carefully. (ProgPartNuclPhys.72.1)

Thank you for your attention

slide-35
SLIDE 35

Final thoughts

“[I]s it possible to interpret the neutron data in terms of the elementary weak interaction and mesonic couplings? The problem is usually decomposed into two fairly independent parts. In a first step, the effective parity-violating nucleon-nucleon interaction is calculated from the elementary weak interaction by taking into account the nuclear medium surrounding the two interacting nucleons. In a second step, this effective interaction is propagated into the huge shell-model spaces typical for compound-nucleus states at neutron threshold ... it is possible to determine the rms matrix element v and the spreading width ... The spreading width is found to lie in the expected range of 10−6 eV.” (RevModPhys.71.445) Since the 1980’s, most PV calculations have been expressed in terms of the DDH parameters. More recently EFT descriptions, both with and without explicit pion degrees of freedom, have been adopted to ensure consistency between PC and PV interactions and currents. Finally, instead of using the Lagrangian directly, hybrid calculations use a potential derived from the EFT Lagrangian combined with models for the PC interactions. ... we attempt to create a dictionary, to the extent possible ... There are some inherent uncertainties involved, particularly when cutoffs and subtraction points in one scheme are not compatible with another, so some of these translations cannot be considered exact and should be interpreted carefully. (ProgPartNuclPhys.72.1)

Thank you for your attention

slide-36
SLIDE 36

Final thoughts

“[I]s it possible to interpret the neutron data in terms of the elementary weak interaction and mesonic couplings? The problem is usually decomposed into two fairly independent parts. In a first step, the effective parity-violating nucleon-nucleon interaction is calculated from the elementary weak interaction by taking into account the nuclear medium surrounding the two interacting nucleons. In a second step, this effective interaction is propagated into the huge shell-model spaces typical for compound-nucleus states at neutron threshold ... it is possible to determine the rms matrix element v and the spreading width ... The spreading width is found to lie in the expected range of 10−6 eV.” (RevModPhys.71.445) Since the 1980’s, most PV calculations have been expressed in terms of the DDH parameters. More recently EFT descriptions, both with and without explicit pion degrees of freedom, have been adopted to ensure consistency between PC and PV interactions and currents. Finally, instead of using the Lagrangian directly, hybrid calculations use a potential derived from the EFT Lagrangian combined with models for the PC interactions. ... we attempt to create a dictionary, to the extent possible ... There are some inherent uncertainties involved, particularly when cutoffs and subtraction points in one scheme are not compatible with another, so some of these translations cannot be considered exact and should be interpreted carefully. (ProgPartNuclPhys.72.1)

Thank you for your attention

slide-37
SLIDE 37

Final thoughts

“[I]s it possible to interpret the neutron data in terms of the elementary weak interaction and mesonic couplings? The problem is usually decomposed into two fairly independent parts. In a first step, the effective parity-violating nucleon-nucleon interaction is calculated from the elementary weak interaction by taking into account the nuclear medium surrounding the two interacting nucleons. In a second step, this effective interaction is propagated into the huge shell-model spaces typical for compound-nucleus states at neutron threshold ... it is possible to determine the rms matrix element v and the spreading width ... The spreading width is found to lie in the expected range of 10−6 eV.” (RevModPhys.71.445) Since the 1980’s, most PV calculations have been expressed in terms of the DDH parameters. More recently EFT descriptions, both with and without explicit pion degrees of freedom, have been adopted to ensure consistency between PC and PV interactions and currents. Finally, instead of using the Lagrangian directly, hybrid calculations use a potential derived from the EFT Lagrangian combined with models for the PC interactions. ... we attempt to create a dictionary, to the extent possible ... There are some inherent uncertainties involved, particularly when cutoffs and subtraction points in one scheme are not compatible with another, so some of these translations cannot be considered exact and should be interpreted carefully. (ProgPartNuclPhys.72.1)

Thank you for your attention

slide-38
SLIDE 38

Issue: time dependence of parameters in SM Lagrangian

Is this an issue?

◮ Quasar absorption spectra =

⇒ Space-time variation of α?

Cameron & Pettitt, arXiv:1207.6223

slide-39
SLIDE 39

What is Oklo?

slide-40
SLIDE 40

Relative magnitudes of

  • ∆α

α

  • and
  • ∆Xq

Xq

◮ Unification at some scale implies

  • ∆Xq

Xq

  • (R − λ − 0.8κ) ∆α

α

  • Langacker et al. (2001)
slide-41
SLIDE 41

Relative magnitudes of

  • ∆α

α

  • and
  • ∆Xq

Xq

◮ Unification at some scale implies

  • ∆Xq

Xq

  • (R − λ − 0.8κ) ∆α

α

  • Langacker et al. (2001)

◮ R ≃ π 12α−1(MZ) = 34

slide-42
SLIDE 42

Relative magnitudes of

  • ∆α

α

  • and
  • ∆Xq

Xq

◮ Unification at some scale implies

  • ∆Xq

Xq

  • (R − λ − 0.8κ) ∆α

α

  • Langacker et al. (2001)

◮ R ≃ π 12α−1(MZ) = 34 ◮ BUT

  • ln mp

me

  • ∼ (R − λ − 0.8κ) ∆ (ln α)

Experimental results for ∆

  • ln mp

me

  • , ∆ (ln α)

     = ⇒

  • ∆Xq

Xq

  • ∆α

α

slide-43
SLIDE 43

Interpretation of Oklo: earlier estimates of a

(in MeV) [Flambaum & Wiringa (2009)]

◮ Estimate 1: VMC study (with AV18+UIX) of “a” in light nuclei mq mV ∆mV ∆mq

6He 6Li 7He 7Li 7Be 8Be 9Be

“a” 0.03 9.92 9.52 11.7 15.4 15.5 17.2 16.2 14 0.06 0.60 1.39 2.01 −0.23 0.62 −1.67 3.94 1.0 ◮ Estimate 2: Walecka model with Fermi gas model estimate for shift ∆′

r

due to ∆Xq ∆′

r

U0 ≈ − ∆mN mN + 2∆r0 r0 + ∆U0 U0

  • Independent of A

(R = r0A

1 3 )

Focus on potential well depth or U0-term

(Ignore ∆r0)

∆′

r

U0 = 7.50∆mS mS − 5.50∆mV mV − ∆mN mN = ⇒ a =

  • 6

12

slide-44
SLIDE 44

Interpretation of Oklo: earlier estimates of a

(in MeV) [Flambaum & Wiringa (2009)]

◮ Estimate 1: VMC study (with AV18+UIX) of “a” in light nuclei mq mV ∆mV ∆mq

6He 6Li 7He 7Li 7Be 8Be 9Be

“a” 0.03 9.92 9.52 11.7 15.4 15.5 17.2 16.2 14 0.06 0.60 1.39 2.01 −0.23 0.62 −1.67 3.94 1.0 ◮ Estimate 2: Walecka model with Fermi gas model estimate for shift ∆′

r

due to ∆Xq ∆′

r

U0 ≈ − ∆mN mN + 2∆r0 r0 + ∆U0 U0

  • Independent of A

(R = r0A

1 3 )

Focus on potential well depth or U0-term

(Ignore ∆r0)

∆′

r

U0 = 7.50∆mS mS − 5.50∆mV mV − ∆mN mN = ⇒ a =

  • 6

12

slide-45
SLIDE 45

Interpretation of Oklo: earlier estimates of a

(in MeV) [Flambaum & Wiringa (2009)]

◮ Estimate 1: VMC study (with AV18+UIX) of “a” in light nuclei mq mV ∆mV ∆mq

6He 6Li 7He 7Li 7Be 8Be 9Be

“a” 0.03 9.92 9.52 11.7 15.4 15.5 17.2 16.2 14 0.06 0.60 1.39 2.01 −0.23 0.62 −1.67 3.94 1.0 ◮ Estimate 2: Walecka model with Fermi gas model estimate for shift ∆′

r

due to ∆Xq ∆′

r

U0 ≈ − ∆mN mN + 2∆r0 r0 + ∆U0 U0

  • Independent of A

(R = r0A

1 3 )

Focus on potential well depth or U0-term

(Ignore ∆r0)

∆′

r

U0 = 7.50∆mS mS − 5.50∆mV mV − ∆mN mN = ⇒ a =

  • 6

12