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  • Pseudoritial temperature and equation of statefrom Nf = 2 twisted mass lattie QCDFlorian BurgerHumboldt-Universität zu BerlinSt. Goar � Marh, 2013

  • 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)

  • OutlineMotivation and SetupT and Chiral SenariosThermodynami Equation of StateConlusions

    3 / 25

  • OutlineMotivation and SetupT and Chiral SenariosThermodynami Equation of StateConlusions

    4 / 25

  • 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

  • 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℄

  • Simulation Points

    320 400 480 700

    mπ[MeV]

    A B C D

    Nτ = 6

    8

    10

    12

    7 / 25

  • OutlineMotivation and SetupT and Chiral SenariosThermodynami Equation of StateConlusions

    8 / 25

  • 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:

  • 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

  • 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

  • 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

  • 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

  • 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℄

  • 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

  • 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)

  • OutlineMotivation and SetupT and Chiral SenariosThermodynami Equation of StateConlusions

    17 / 25

  • 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

  • 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

  • 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

  • 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

  • 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 «

  • 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

  • OutlineMotivation and SetupT and Chiral SenariosThermodynami Equation of StateConlusions

    24 / 25

  • 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

  • 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

  • Renormalization of Re(L)〈TrL̂†(~x)TrL̂(~0)〉 = e−Fq̄q (~x,T )−F0(T )T →T→0 e−V (|~x|)T

    27 / 25

  • Renormalization of 〈ψ̄ψ〉〈ψψ〉ren = ZP(〈χ̄iγ5τ3χ〉bare + µ P(β)a2 )+ . . .

    28 / 25

  • 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

  • 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

  • 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