m.people.physik.hu-berlin.de/~burger/talks/stgoar_2013.pdf · 2014. 11. 20. · r ma rch, 2013. 2 /...
TRANSCRIPT
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Pseudoritial temperature and equation of statefrom Nf = 2 twisted mass lattie QCDFlorian BurgerHumboldt-Universität zu BerlinSt. Goar � Marh, 2013
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2 / 25
tmfT-Collaboration:E. M. Ilgenfritz (Joint Institute for Nulear Researh, Dubna)M. Kirhner, M. Müller-Preuÿker (HU Berlin),M. P. Lombardo (INFN Frasati),C. Urbah (Uni Bonn),O. Philipsen, L. Zeidlewiz, C. Pinke (Uni Frankfurt)
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OutlineMotivation and SetupT and Chiral SenariosThermodynami Equation of StateConlusions
3 / 25
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OutlineMotivation and SetupT and Chiral SenariosThermodynami Equation of StateConlusions
4 / 25
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Motivation◮ Explore �nite T phase transition/rossover for Nf = 2 QCD atvanishing hemial potential◮ Order of transition in the hiral limit not known yet for Nf = 2◮ Argued to be in universality lass of O(4) 3-dim spin modell[R. D. Pisarski, F. Wilzek, 84℄However 1st order not ruled out(e. g. C.Bonati et al. 2009, C. Bonati et al. 2011)◮ Nf = 2 equation of state → useful to study onset of massthresholds in thermodynamis◮ Alternative disretization worthwhile to study systematis◮ Considered observables (so far):Suseptibilities, renorm. L and 〈ψ̄ψ〉, equation of state,gluon and ghost propagators (see A. Sternbek's talk) 5 / 25
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Twisted Mass Lattie Regularization◮ Nf = 2 Wilson twisted mass ation at maximal twist:Sf [U, ψ, ψ] =∑x χ(x) (1− κH[U] + 2iκaµγ5τ3)χ(x)
ψ =1√2 (1 + iγ5τ3)χ and ψ = χ 1√2(1 + iγ5τ3)
◮ Advantage: when κ tuned to ritial value κ :Automati O(a) improvement◮ Disadvantage: expliit �avor symmetry breaking (mostly small, buthas to be heked)◮ Tree level improved gauge ation:Sg [U] = β(0∑P [1− 13ReTr (UP)] + 1∑R [1− 13ReTr (UR)]) 6 / 25
[R. Frezzotti, G.C. Rossi, 2004℄
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Simulation Points
320 400 480 700
mπ[MeV]
A B C D
Nτ = 6
8
10
12
7 / 25
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OutlineMotivation and SetupT and Chiral SenariosThermodynami Equation of StateConlusions
8 / 25
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Signals for the Crossover: Polyakov Loop◮ Polyakov loop suseptibility (no onvining signal)
χRe(L)χRe(L)
β
4.204.154.104.054.003.953.903.85
0.09
0.085
0.08
0.075
0.07
0.065
0.06
0.055 9 / 25
mπ ≈ 400 MeV:
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Disonneted Chiral Suseptibility
10 / 25
σ〈ψ̄ψ〉 = V /T (〈ψ̄ψ2〉− 〈ψ̄ψ〉2) mπ ≈ 320 MeV:Gaussian fitA12σ2ψ̄ψβ
4.003.943.883.82
0.8
0.7
0.6
0.5
0.4
0.3
0.2mπ ≈ 400 MeV:Gaussian fit
B12σ2ψ̄ψ
β
4.023.963.903.84
0.5
0.4
0.3
0.2
0.1
mπ ≈ 480 MeV:Gaussian fit
C12σ2ψ̄ψ
β
4.064.003.943.88
0.4
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0
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Renormalized Re(L), 〈ψ̄ψ〉
11 / 25
R〈ψψ〉 = 〈ψψ〉(T , µ) − 〈ψψ〉(0, µ) + 〈ψψ〉(0, 0)〈ψψ〉(0, 0) 0
0.2
0.4
0.6
0.8
1
180 200 220 240 260 280
R<
ψψ
>
T [MeV]
Nτ = 12Nτ = 10
〈Re(L)〉R = Re(L) exp (V (r0)/2T ) 0
0.5
1
1.5
2
180 220 260 300 340 380 420
<R
e(L)
>R
T [MeV]
Nτ = 12Nτ = 10
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Renormalized Re(L), 〈ψ̄ψ〉
12 / 25
R〈ψψ〉 = 〈ψψ〉(T , µ) − 〈ψψ〉(0, µ) + 〈ψψ〉(0, 0)〈ψψ〉(0, 0) 0
0.2
0.4
0.6
0.8
1
180 200 220 240 260 280
R<
ψψ
>
T [MeV]
Nτ = 12Nτ = 10
〈Re(L)〉R = Re(L) exp (V (r0)/2T )B12Fit
〈Re(L)〉R
T [MeV]
360320280240200
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
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Results
13 / 25
Ensemble B12 C12 D8T [MeV], σ2〈ψ̄ψ〉: 217(5) 229(5) 251(10)T [MeV], 〈Re(L)〉R : 249(5) 258(5) 266(11)Signals for deon�nement and restoration of hiral symmetry atdi�erent loations in rossover region
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O(4) Magneti EoS◮ Near ritial point of a 2nd order transition: universality◮ Expet data to ollaps on universal urve [J. Engels & T. Mendes, 99℄◮ 〈ψ̄ψ〉 = h1/δ f (d z) + aττh + b1h + . . .
︸ ︷︷ ︸saling violating termsτ = β − βhiral, h = 2 a µ, z = τ/h1/(β̃δ)
◮ Connetion to spin model:〈ψ̄ψ〉 ∼ M (magnetization)µ ∼ H (external �eld)β ∼ T (temperature) 14 / 25
f(z)
O(4)
z
43210-1-2-3
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
[S. Ejiri et al., 2009℄
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O(4) Magneti EoS
15 / 25
Pion Mass:C12: 480 MeVB12: 400 MeVA12: 320 MeVC12B12A12z
〈ψ̄ψ〉/h
1/δ
43.532.521.510.50
0.13
0.12
0.11
0.1
0.09
0.08
0.07
0.06
0.05
0.04 C12 corr.B12 corr.A12 corr.
z
〈ψ̄ψ〉/h
1/δ
-(s
caling
corr
.)
3.532.521.510.5
0.035
0.03
0.025
0.02
0.015
0.01Result: βhiral ≈ 3.76(2) →T(mπ = 0) ≈ 166 MeV
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Chiral Limit Senarios from Spin Models
16 / 25
◮ From universal funtion h1/δf (z) one an show:T(mπ) = T(0) + Am2/(β̃δ)π1st : T(0) = 182(14) MeVO(4): T(0) = 152(26) MeV 140 160 180
200
220
240
260
0 100 200 300 400 500
Tc
(MeV
)
mπ (MeV)
1st order
O(4)
mπ,c = 0 MeV
mπ,c = 200 MeVZ(2)
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OutlineMotivation and SetupT and Chiral SenariosThermodynami Equation of StateConlusions
17 / 25
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Integral Method◮
ǫ =TV ∂ lnZ∂ lnT ∣∣∣∣V p = T ∂ lnZ∂V ∣∣∣∣T
◮ Trae anomaly (interation measure):I = ǫ− 3p = −TV d lnZd ln a◮ Starting point for p(T ) and ǫ(T ) viaIT 4 = T ∂∂T ( pT 4) pT 4 − p0T 40 = ∫ TT0 dτ ǫ− 3pτ5 ∣∣∣∣LCPon lines of onstant physis (LCP) 18 / 25
But: V = N3σ a3T = 1Nτ a
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Trae Anomaly◮ IT 4 = ǫ− 3pT 4 = − TT 4 V d lnZd ln a
= N4τ
(adβda )(03 〈ReTrUP〉sub + 13 〈ReTrUR〉sub+∂κ∂β
〈χ̄H[U]χ〉sub − (2aµ∂κ∂β + 2κ ∂(aµ)∂β )〈χ̄iγ5τ3χ〉sub)◮ Starting point for p(T ) and ǫ(T ) by integral method◮ Subtrated expetation values: 〈. . .〉sub ≡ 〈. . .〉T>0 − 〈. . .〉T=0
→ interpolations for T = 0 data◮ Preliminary results for mπ ≈ 400 MeV and mπ ≈ 700 MeV 19 / 25
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Trae anomaly - Lattie Artifats
20 / 25
mπ ≈ 700 MeV:Nτ = 4Nτ = 6Nτ = 8Nτ = 10ǫ−3p
T 4
T [MeV]
800700600500400300200
12
10
8
6
4
2
0
-2
mπ ≈ 400 MeV:Nτ = 4Nτ = 6Nτ = 8Nτ = 10Nτ = 12ǫ−3p
T 4
T [MeV]
800700600500400300200
12
10
8
6
4
2
0
-2
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Trae Anomaly, Tree Level Corretions◮ Observe large lattie artifats in IT 4◮ Lattie pressure in the free limit pLSB known: [P. Hegde et al., 2008℄◮ Twisted mass ation: [O. Philipsen & L. Zeidlewiz, 2010℄◮ Correted by division by pLSB/pCSB [S. Borsanyi et al., 2010℄
21 / 25mπ ≈ 700 MeV: mπ ≈ 400 MeV:
correcteduncorrectedǫ−3p
T 4
T = 318 MeV
1/N2τ
0.030.0250.020.0150.010.0050
10
9
8
7
6
5
4
3
2
correcteduncorrectedǫ−3p
T 4
T = 285 MeV
1/N2τ
0.030.0250.020.0150.010.0050
14
12
10
8
6
4
2
correcteduncorrectedǫ−3p
T 4
T = 391 MeV
1/N2τ
0.030.0250.020.0150.010.0050
6
5
4
3
2
1
0
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Correted Trae Anomaly & Interpolation
22 / 25
mπ ≈ 700 MeV:Nτ = 6Nτ = 8Nτ = 10
Interpolationǫ−3pT 4
T [MeV]
900700500300100
10
8
6
4
2
0
-2
mπ ≈ 400 MeV:Nτ = 4Nτ = 6Nτ = 8Nτ = 10Nτ = 12
Interpolationǫ−3pT 4
T [MeV]
900700500300100
10
8
6
4
2
0
-2Interpolation for orreted I/T 4 [S. Borsanyi et al., 2010℄ :IT 4 = exp `−h1t̄ − h2t̄2´ · „h0 + f0 {tanh f1t̄ + f2}1 + g1 t̄ + g2 t̄2 «
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Pressure and Energy Density
23 / 25
pT 4 − p0T 40 = ∫ TT0 dτ ǫ− 3pτ5 ∣∣∣∣LCPmπ ≈ 700 MeV:0
4
8
12
16
200 300 400 500 600 700 800
1 1.5 2 2.5 3
T [MeV]
× TTc
3pSB
D mass (ǫ− 3p)/T4
ǫ/T 4
3p/T 4
mπ ≈ 400 MeV:0
4
8
12
16
200 300 400 500 600
1 1.5 2 2.5
T [MeV]
× TTc
3pSB
B mass (ǫ− 3p)/T4
ǫ/T 4
3p/T 4
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OutlineMotivation and SetupT and Chiral SenariosThermodynami Equation of StateConlusions
24 / 25
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Conlusions & Outlook◮ Conlusions:- T for pion masses in the range 300 - 700 MeV- Chiral limit so far inonlusive- O(4) saling ompatible up to saling violation terms- Thermodynami equation of state for two pion masses- Have to further improve preision at T > 0 and T = 0◮ Outlook:- Nf = 2 + 1 + 1 25 / 25
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Comparison with DIK-Collaboration
26 / 25
(G. Shierholz et. al) from σ〈ψ̄ψ〉:our data (tmfT)
DIK: arXiv:1102.4461DIK: arXiv:0910.2392
r0Tc
r0mπ
1.81.61.41.210.80.60.40.2
0.75
0.7
0.65
0.6
0.55
0.5
0.45
0.4
0.35
0.3
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Renormalization of Re(L)〈TrL̂†(~x)TrL̂(~0)〉 = e−Fq̄q (~x,T )−F0(T )T →T→0 e−V (|~x|)T
27 / 25
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Renormalization of 〈ψ̄ψ〉〈ψψ〉ren = ZP(〈χ̄iγ5τ3χ〉bare + µ P(β)a2 )+ . . .
28 / 25
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T = 0 Subtrations & Interpolations
29 / 25
example: plaquette:ReTr〈UP 〉0.64
0.6
0.56
Residuals of fit
β
4.34.13.9
30
-3
Residuals of fit
β
4.34.13.9
30
-3
β = 3.70, aµ = 0.009, mπ ≈ 400 MeV 0.55
0.552
0.554
0.556
0.558
0.56
0 1000 2000 3000 4000 5000 6000 7000 8000 9000
plaq
uette
No traj.
beta=3.70, 16^3x24
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β-Funtion
30 / 25
[M. Cheng et al.: Phys.Rev. D77:014511, 2008℄“a dβda ” = − ` rχa ´ „ d( rχa )dβ «−1` rχa ´ (β) = 1+n0R(β)2d0(a2L(β)+d1R(β)2) R(β) = a2L(β)a2L(3.9) r0 = 0.420(15) fm
Interpolationr0/arχ/a
β
4.64.354.24.053.93.83.65
14
12
10
8
6
4
2-loopadβda
β
4.64.354.24.053.93.83.65
0
-0.1
-0.2
-0.3
-0.4
-0.5
-0.6
-0.7
-0.8
-0.9
-
Tree Level Corretions (loser look), SB (Free) LimitLattie:pLF (µ)T 4 = 3∫[0,2π)3 d3k(2π)3 1Nt Nt−1∑n=0 lnDet (|G (k)|2 + (aµ)2)G (k) = (am) + 2r∑µ
sin2(akµ2 )+ i∑µ
γµ sin(akµ)Continuum: pCF (µ/T )T 4 = 278 π290g(µ/T )g(µ/T ) = 3607π4 ∫ ∞µ/T dx x√x2 − (µ/T )2 ln(1 + e−x)Corretion: Nτ 4 6 8 10 12pLSB/pCSB 2.586 1.634 1.265 1.134 1.084 . 31 / 25
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Lines of Constant Physis, onstant mπ
32 / 25
mπ ≈ 700 MeV: presently ful�lled up to 10 %D8
mPS [MeV]
β
4.54.44.34.24.143.93.83.73.6
900
850
800
750
700
650
600
550
500
mπ ≈ 400 MeV:340
360
380
400
420
440
460
480
3.70 3.8 3.9 4.05 4.2
β
mPS [MeV]
B mass
ETMCtmfT
Motivation and SetupTc and Chiral ScenariosThermodynamic Equation of StateConclusionsAppendix