ua(1) anomaly - kek · 2010-11-08 · lattice results: jlqcd, prl101, 122002 (2010) and a full...

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Page 1: UA(1) anomaly - KEK · 2010-11-08 · Lattice results: JLQCD, PRL101, 122002 (2010) and a full paper (in preparation) • 2 and 2+1 flavors • p and e regimes (various quark masses)
Page 2: UA(1) anomaly - KEK · 2010-11-08 · Lattice results: JLQCD, PRL101, 122002 (2010) and a full paper (in preparation) • 2 and 2+1 flavors • p and e regimes (various quark masses)

UA(1) anomaly

give chiral condensate

Page 3: UA(1) anomaly - KEK · 2010-11-08 · Lattice results: JLQCD, PRL101, 122002 (2010) and a full paper (in preparation) • 2 and 2+1 flavors • p and e regimes (various quark masses)

ρ(λ) = 1V

δ (λ − λk )k∑ ,

qq =1V

1m + iλkk

limm→0

limV→∞

ρ(λ = 0) = Σπ

free quark

Banks, Casher (1980)

accumulation of near‐zero modes = “quark‐antiquark condensate”

Page 4: UA(1) anomaly - KEK · 2010-11-08 · Lattice results: JLQCD, PRL101, 122002 (2010) and a full paper (in preparation) • 2 and 2+1 flavors • p and e regimes (various quark masses)

D = ρa1+ γ 5 sgn(aHW )⎡⎣ ⎤⎦ , aHW = γ 5(aDW − ρ)

Page 5: UA(1) anomaly - KEK · 2010-11-08 · Lattice results: JLQCD, PRL101, 122002 (2010) and a full paper (in preparation) • 2 and 2+1 flavors • p and e regimes (various quark masses)

λk2 + m2( )

k∏

p‐regime ε‐regime

Page 6: UA(1) anomaly - KEK · 2010-11-08 · Lattice results: JLQCD, PRL101, 122002 (2010) and a full paper (in preparation) • 2 and 2+1 flavors • p and e regimes (various quark masses)

Lattice results:    JLQCD, PRL101, 122002 (2010)   and a full paper (in preparation) •  2 and 2+1 flavors  •  p and e regimes (various quark masses) •  163x48 and 243x48 •  various topological charges

pion zero‐mode integral pion loop

Page 7: UA(1) anomaly - KEK · 2010-11-08 · Lattice results: JLQCD, PRL101, 122002 (2010) and a full paper (in preparation) • 2 and 2+1 flavors • p and e regimes (various quark masses)
Page 8: UA(1) anomaly - KEK · 2010-11-08 · Lattice results: JLQCD, PRL101, 122002 (2010) and a full paper (in preparation) • 2 and 2+1 flavors • p and e regimes (various quark masses)

ΣMS (2GeV) = [242(04)(−18+19 ) MeV]3

Σ(mud ,ms ) = Σ(0,ms ) ×

1− 3Mπ2

32π 2F2 lnMπ

2

µ2 +32L6Mπ

2

F2

⎣⎢

⎦⎥

Page 9: UA(1) anomaly - KEK · 2010-11-08 · Lattice results: JLQCD, PRL101, 122002 (2010) and a full paper (in preparation) • 2 and 2+1 flavors • p and e regimes (various quark masses)

Derek Leinweber

χt =Q2

V= d 4x q(x)q(0)∫

JLQCD, PLB665, 294 (2008)

Aoki et al, PRD76, 054508 (2007)

Near‐zero modes dominates in     the disconnected diagrams

Page 10: UA(1) anomaly - KEK · 2010-11-08 · Lattice results: JLQCD, PRL101, 122002 (2010) and a full paper (in preparation) • 2 and 2+1 flavors • p and e regimes (various quark masses)

χt = mΣ / N f , or

χt =Σ

mu−1 + md

−1 + ms−1

Crewther (1977),  Leutwyler‐Smilga (1992)

Nf=2+1

Nf=2

ΣMS (2GeV) = [247(03)(XX) MeV]3

Page 11: UA(1) anomaly - KEK · 2010-11-08 · Lattice results: JLQCD, PRL101, 122002 (2010) and a full paper (in preparation) • 2 and 2+1 flavors • p and e regimes (various quark masses)

Σ ≡ − qq = 0

Page 12: UA(1) anomaly - KEK · 2010-11-08 · Lattice results: JLQCD, PRL101, 122002 (2010) and a full paper (in preparation) • 2 and 2+1 flavors • p and e regimes (various quark masses)

non‐singlet singlet

scalar δ σ

pseudo‐scalar π η’ UA(1)

χπ − χδ = d 4x jπ (x) jπ (0) − jδ (x) jδ (0) = dλρ(λ) 4m2

λ2 + m2( )2∫∫

Near‐zero mode dominates. Others m2 → 0  

Page 13: UA(1) anomaly - KEK · 2010-11-08 · Lattice results: JLQCD, PRL101, 122002 (2010) and a full paper (in preparation) • 2 and 2+1 flavors • p and e regimes (various quark masses)

Σ = dλρ(λ) 2mλ2 + m2∫ = 0

χπ − χδ = dλρ(λ) 4m2

λ2 + m2( )2∫ = 0

Shuryak (1994), Cohen (1996).

always occurs together?

ρ(λ) ~ m2δ (λ)

Schafer (1996) Instanton Liquid Model see also, Lee, Hatsuda (1996)

Page 14: UA(1) anomaly - KEK · 2010-11-08 · Lattice results: JLQCD, PRL101, 122002 (2010) and a full paper (in preparation) • 2 and 2+1 flavors • p and e regimes (various quark masses)

β a (fm) T (MeV) T/Tc

2.35 0.13 250 0.86

2.445 0.114 288 1

2.55 0.094 350 1.20

β a (fm) T (MeV) T/Tc

2.18 0.144 172 0.90

2.20 0.139 177 0.93

2.30 0.118 209 1.09

2.40 0.101 243 1.27

2.45 0.094 262 1.38

Tc = 190 MeV (fixed)

Page 15: UA(1) anomaly - KEK · 2010-11-08 · Lattice results: JLQCD, PRL101, 122002 (2010) and a full paper (in preparation) • 2 and 2+1 flavors • p and e regimes (various quark masses)

Tc

1.2 Tc

Page 16: UA(1) anomaly - KEK · 2010-11-08 · Lattice results: JLQCD, PRL101, 122002 (2010) and a full paper (in preparation) • 2 and 2+1 flavors • p and e regimes (various quark masses)

limx→∞

q(x)q(0)Q= limx→∞

mP(x)mP(0)Q= − 1V

χt −Q2

V+c42χtV

...⎛

⎝⎜⎞

⎠⎟+O(e−mη 'x )

fP1

p2 + mπ2 m0

2 1p2 + mπ

2 fP + const

~ fP2m0

2

4mπ3 (1+ mπ x)e

−mπ x + const

β=2.40. am=0.025, 0.01 Approx the disconnected diagram   by only the near‐zero modes: 

Page 17: UA(1) anomaly - KEK · 2010-11-08 · Lattice results: JLQCD, PRL101, 122002 (2010) and a full paper (in preparation) • 2 and 2+1 flavors • p and e regimes (various quark masses)

Gattringer et al. (2002) 163x6

T=0:  ~ 191(5) MeV Del Debbio et al. (2008)

ours, 243x6

Difference need to be understood, c4/χtV ? 

Page 18: UA(1) anomaly - KEK · 2010-11-08 · Lattice results: JLQCD, PRL101, 122002 (2010) and a full paper (in preparation) • 2 and 2+1 flavors • p and e regimes (various quark masses)

T ~ 1.1 Tc

Page 19: UA(1) anomaly - KEK · 2010-11-08 · Lattice results: JLQCD, PRL101, 122002 (2010) and a full paper (in preparation) • 2 and 2+1 flavors • p and e regimes (various quark masses)
Page 20: UA(1) anomaly - KEK · 2010-11-08 · Lattice results: JLQCD, PRL101, 122002 (2010) and a full paper (in preparation) • 2 and 2+1 flavors • p and e regimes (various quark masses)

ρ(λ) ~ m2δ (λ)

Page 21: UA(1) anomaly - KEK · 2010-11-08 · Lattice results: JLQCD, PRL101, 122002 (2010) and a full paper (in preparation) • 2 and 2+1 flavors • p and e regimes (various quark masses)