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Lecture 3:Parameters and Renormalization Group issues in the SM
Outline of Lecture 3:¯ The SM renormalization group equations
o SM RG running at NNLO° Matching conditions for MS parameters in terms of physical parameters
o Matching relation for the effective Fermi constanto The issue of tadpoles and non-decoupling of heavy particleso Matching and running of the top masso The top Yukawa coupling from form Mt
o The Higgs self-coupling form MH
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 147
A summary and outlook of Lecture 2
The SM as a LEET and the impact of the LEESM scenario
The SM provides a rather compact and fairly simple theory of elementaryparticles with peculiar properties like interactions mediated by gaugeinteraction related to local S U(3)c ⊗ S U(2)L ⊗ U(1)Y → S U(3)c ⊗ U(1)emnon-Abelian times Abelian structure. Speculative extension like GUTs,SUSY-GUTs, sequential Fermions, Strings, String-Compactification etc.have no phenomenological support.
Most of the peculiar properties of the SM are supported by a LEET scenario:renormalizability, Yang-Mills interaction structure, fermion-family structure,the need for the Higgs etc.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 148
Remember: the electroweak SM has been obtained as the�
�
�
�minimal renormalizable extension
of the phenomenologically established QED and non-renormalizable weakcharged current Fermi theory. What a wealth of predictions have been madeat the beginning of the 1970’s which have turned out to be reality while noother stuff has been found in 45 years! 3rd family was a surprise, masseswere unknown
v the main impact of the LEESM hypothesis is that the bare “theory” is phys-ical, the cut-off is physical and finite and one is able to calculate the bareparameters from the phenomenologically known renormalized ones.
v as we expect/assume the cut-off to be the Planck scale: all non-renormalizable effects are dramatically suppressed at low energies includ-ing any existing and future accelerator energy (except from possible cos-mic accelerators)
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 149
v as the Planck scale also sets the scale for the cosmic Big Bang event,we actually get access to early cosmology which is governed by shortdistance physics there, i.e. by the bare system the effective parametersof which we have access to by calculating the bare parameters from theknown low energy parameters.
v as we will see in such scenario the Higgs system will play a major role inthe early universe, provided the calculations of the effective parametersactually is possible up to the Planck scale (which turns out to be a matterof the existence of an appropriate window in the SM parameter space)
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 150
l On SM parameters and the status of the SM
The attempt of an extrapolation of the SM to very high energy scalesrequires a very precise knowledge of the SM and its parameters. In thefollowing section I will give a brief overview about the SM status afterLEP/SLD, Tevatron and the first results from the LHC.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 151
On SM parameters
❏ Motivation: old – the quest for gauge unification
Precise SM predictions require to determine the U(1)Y ⊗ SU(2)L ⊗ SU(3)c
SM gauge couplings αem, α2 and αs ≡ α3 (QCD) as accurately as possible
**** a theory can not be better than its input parameters ****
⇒ precision limitations due to non-perturbative hadronic contributions ⇐
❖ beyond SM physics gauge coupling unification?
F. Jegerlehner HU Berlin – July , 2013 –
1
On SM parameters
Do we need new physics? Stability bound of Higgs potential in SM:
SM Higgs remains perturbative up to scale Λ if it is light enough (upper bound=avoiding
Landau pole) and Higgs potential remains stable ( λ > 0 ) if Higgs mass is not too light
[parameters used: mt = 175[150− 200] GeV ; αs = 0.118]
Riesselmann, Hambye 1996
Key object of our interest:
the Higgs potential☛✡
✟✠V = m2
2H2 + λ
24H4
F. Jegerlehner HU Berlin – July , 2013 –
2
On SM parameters
❏ Motivation: new – running couplings and the Higgs vacuum sta bility
With Higgs from LHC: self-consistency of SM up to the Planck scale: Higgs vacuum stability, origin of Higgs
mechanism etc
The SM dimensionless couplings in the MS scheme as a function of the renormalization scale. The input parameter
uncertainties as given by the line thickness. The green band corresponds to Higgs masses in the range [124-127] GeV.
F. Jegerlehner HU Berlin – July , 2013 –
1
On SM parameters
The Parameters of the Standard Model
− in four fermion and vector boson processes −original focus at LEP times
our focus
g1 = g′, g2 = g ⇔ αem , sin 2Θeff
Thomsonscattering
pp, e+e−
pp, e+e−
µ–decay
e+e− → ff
e+e− → e+e−
νe, νN
α
MW
MZ
Gµ
vf , af
sin2 ΘW
SU(2)L ⊗ U(1)Y
Higgs mechanism
g2, g1, vunlike in QED and QCD in SM (SBGT)
parameter interdependence
☞
only 3 independent quantities
(besides fermion masses and mixing parameters)
α, Gµ, MZ
⇓parameter relationships between very precisely measurable quantities
precision tests, possible sign of new physics
F. Jegerlehner HU Berlin – July , 2013 –
1
On SM parameters
First basic constraints via virtual effects on top Yukawa ( mt and coupling yt) and Higgs
potential ( mH and self-coupling λ) ⇒ top at Tevatron, Higgs at LHC confirmed.✗
✖
✔
✕Now in the focus interplay between
gauge couplings g1, g2, g3, top Yukawa coupling yt and Higgs self-coupling λ
Test of quantum effects
Prototype QED:
γ γ γ
γ
µ
µ
vacuum polarization→ Lamb shiftαem shift (6%)
form factors→ anomalous magnetic
moment (99.6%)
LEP/SLC version of g − 2:
√2GµM
2Z sin2 Θi cos
2 Θi = πα (1 + δi)
sin2 Θi = (1− vℓ/aℓ)/4, 1−M2W/M2
Z , e2/g2, · · · differ by quantum corrections only
SM: renormalizable theory (’t Hooft 1971)
F. Jegerlehner HU Berlin – July , 2013 –
1
v News from LHC: Higgs found, last essential free parameter fixedMH = 125.5 ± 1.5 GeV
v all SM parameters rather precisely known now
MZ = 91.1876(21) GeV, MW = 80.385(15) GeV, Mt = 173.5(1.0) GeV,
GF = 1.16637 × 10−5 GeV−2, α−1 = 137.035999, α(5)s (M2
Z) = 0.1184(7).
Precision predictions:
sin2 Θ f , v f , a f ,MW ,ΓZ,ΓW , g2 · · ·
all depend on α effective (running αem(s))!
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 157
Electroweak fits
New physics sensible observable is the W mass given by
M2W
1 − M2W
M2Z
=πα√
2GF
(1 + ∆r) ; ∆r = f (α,GF,MZ,mt, · · · )
l ∆r model-dependent radiative corrections
l in SUSY models MW is sensitive to the top/stop sector parameters
while
sin2 Θeff =14
(1 − Re
3eff
aeff
)
remains much less affected Buchmuller et al., Heinemeyer et al.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 158
r for MW SUSY looks favored by data!l sensitivity to top/stop sector strongly enhances in MW
l General: MSSM results merge into SM results for larger SUSY masses,as decoupling is at work.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 159
�
�
�
�The SM fits nature!
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 160
On should keep in mind that applying the leading corrections only α(M2Z),
αs(M2Z) and the leading top correction in the ρ-parameters, the remaining
subleading corrections of various origin (self-energy, vertex, box) amount to10 σ effects, which, if not accounted for, would rule out the SM highly!
r SUSY does not yield better global fit! Means SUSY effects on precisionobservables are small, looks like heavier SUSY spectrum favored(decoupling at work)! Higgs at 125 GeV also looks to point in this direction.And the muon g − 2 deviation? A puzzle yet to be solved!
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 161
Most serious persisting 3 − 4σ deviation the Muon g − 2
constraints from LEP, B-physics, g-2, cosmic relict density [plots Olive 09].
m0 scalar mass m1/2 gaugino mass
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 162
After first LHC results:
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 163
Kazakov, de Boer et al.
l with the Higgs found at 125 GeV muon g − 2 looks to me in trouble.If δaµ is not SUSY, what else?Most other NP scenarios give likely even smaller contributions!At least GUT-SUSY scenarios likely cannot explain it!
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 164
Many open questions in the Standard Model
Standard Model very good description– Less satisfactory explanations
5 Why 3 families of fundamental fermions ?
5 Why P, C and CP violations? Why not more CP ?5 Strong CP problem ?5 Why us ? Origin of matter–antimatter asymmetry ?5 What Dark Matter ?5 Why the Cosmological Constant is so tiny ?
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 165
SM parameters are running parameters!
+ −
+−+
−
+−
+−
+− +
−
+−
+−
+−
+−
+−
+−
+−
+−
+ −r
−
−
γ virtual
pairs
γ
µ− µ−
µ− µ−
γ∗ → e+e−, µ+µ−, τ+τ−, uu, dd, · · · → γ∗
↑ tLHC ∼ 1.66 × 10−15 secIn a collision of impact energy E the effective charge is the charge contained
in the sphere of radius r ' 1/E, which due to vacuum polarization is largerthan the classical charge seen in a large sphere (r → ∞)
⇒ charge screening (charge renormalization) running charge.electromagnetic interaction strength decreases with distance
Running parameters αem and αs
r QED Abelian U(1)em
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 166
A compilation of the QCD coupling αs measurements. The lowest pointshown is at the τ lepton mass Mτ = 1.78 GeV where αs(Mτ) = 0.322 ± 0.030
↑ tLEPI ∼ 2.58 × 10−11 sec
r non-Abelian gauge theories responsible for weak [local S U(2) symmetry]and strong [local S U(3) symmetry] interactions are anti-screening≡ Asymptotic Freedom (AF) Gross, Wilczek, Politzer 1973 [NP 2004]
strong interaction strength increases with distance
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 167
The SM running parameters
The SM dimensionless couplings in the MS scheme as a function of therenormalization scale for MH = 124 − 127 GeV.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 168
¯ The SM renormalization group equations
References:1-loop and 2-loop: Gross, Wilczek, Politzer 1973, Jones, Caswell 1974,Tarasov, Vladimirov 1977, Jones 1982, Fischler, Oliensis 1982, Machacek,Vaughn 1983/84/85, Luo, Xiao 20033–loop QCD: Tarasov, Vladimirov, Zharkov 1980, Larin, Vermaseren 19934–loop QCD: Ritbergen, Vermaseren, Larin 1997, Czakon 20052–loop QCD OS vs MS mass: Gray, Broadhurst, Grafe, Schilcher 1990,Fleischer, F.J., Tarasov, Veretin 1999/20003–loop QCD OS vs MS mass: Chetyrkin, Steinhauser 2000, Melnikov,Ritbergen 2000β(3)g′, β(3)
g :Mihaila, Salomon, Steinhauser 2012, Bednyakov, Pikelner, Velizhanin 2012β(3)yt , β
(3)λ :
Chetyrkin, Zoller 2012/2013, Bednyakov, Pikelner, Velizhanin 2012/2013
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 169
As µd/dµ = d/d ln µ it is convenient to use the dimensionless variablet = ln µ/mZ, µ the renormalization scale, mZ the Z boson mass. The RGequations for the relevant couplings may be written as
ddtg′(t) = κβ(1)
g′+ κ2β(2)
g′+ κ3β(3)
g′,
ddtg(t) = κβ(1)
g + κ2β(2)g + κ3β(3)
g ,
ddtg3(t) = κβ(1)
g3+ κ2β(2)
g3+ κ3β(3)
g3,
ddtyt(t) = κβ(1)
yt+ κ2β(2)
yt+ κ3β(3)
yt,
ddtλ(t) = κβ(1)
λ + κ2β(2)λ + κ3β(3)
λ .
The powers of the prefactor κ = 1/(16π2) represents the loop order of theβ-function coefficients.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 170
o SM RG running at NNLOThe β-functions
1-loop
β(1)g′
=416g′3 ,
β(1)g = −
196g3 ,
β(1)g3
= −7g33 ,
β(1)yt
=92y3
t −94g2yt − 8g2
3yt −1712g′2yt ,
β(1)λ =
274g4 +
92g′2g2 − 9λg2 +
94g′4 − 36y4
t + 4λ2 − 3g′2λ + 12y2t λ .
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 171
2-loop
β(2)g′
=443g2
3g′3 +
(92g2 +
19918
g′2 −176y2
t
)g′3 ,
β(2)g = 12g2
3g3 +
(356g2 +
32g′2 −
32y2
t
)g3 ,
β(2)g3
= g33
(92g2 − 26g2
3 +116g′2 − 2y2
t
).
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 172
β(2)yt
= yt
[−108g4
3 + 9g2g23 +
199g′2g2
3 + 36y2t g
23 −
34g′2g2
−234g4 +
1187216
g′4 − 12y4t +
λ2
6+ y2
t
(22516
g2 +13116
g′2 − 2λ)],
β(2)λ = 80g2
3y2t λ − 192g2
3y4t +
9158g6 −
2898g′2g4 −
272y2
t g4
−738λg4 −
5598g′4g2 + 63g′2y2
t g2 +
394g′2λg2 − 3y4
t λ
+452y2
t λg2 −
3798g′6 + 180y6
t − 16g′2y4t −
263λ3 −
572g′4y2
t
−24y2t λ
2 + 6(3g2 + g′2
)λ2 +
62924
g′4λ +856g′2y2
t λ .
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 173
3-loop β-functions of the gauge couplings
β(3)g′
=1315
64g4g′3 − g2g2
3g′3 + 99g4
3g′(t03 +
20596
g2g′5 −13727
g23g′5
−388613
5184g′7 −
78532
g2g′3y2t −
293g2
3g′3y2
t −2827288
g′5y2t +
31516
g′3y4t ,
β(3)g =
3249531728
g7 + 39g5g23 + 81g3g4
3 +29132
g5g′2 −13g3g2
3g′2
−5597576
g3g′4 −72932
g5y2t − 7g3g2
3y2t −
59396
g3g′2y2t +
14716
g3y4t ,
β(3)g3
=109
8g4g3
3 + 21g2g53 +
652g7
3 −18g2g3
3g′2 +
779g5
3g′2
−2615216
g33g′4 −
938g2g3
3y2t − 40g5
3y2t +
10124
g33g′2y2
t + 15g33y
4t .
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 174
The SM gauge couplings running up to MPlanck
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 175
3-loop β-functions of yt and λ in gaugeless limit g′ = g = 0
β(3)yt
= 2[(−
20833
+ 320 ζ3)g63 + (
382712− 114 ζ3)g4
3y2t −
1572g2
3y4t
+(33916
+274ζ3)y6
t +43g2
3y2t λ +
332y4
t λ +596y2
t λ2 −
112λ3
],
β(3)λ = 12
[(−
2663
+ 32 ζ3)g43y
4t + (−38 + 240 ζ3)g2
3y6t − (
15998
+ 36 ζ3)y8t
+16
(1244
3− 48 ζ3)g4
3y2t λ +
16
(895 − 1296 ζ3)g23y
4t λ +
16
(1178− 198 ζ3)y6
t λ +1
36(−1224 + 1152 ζ3)g2
3y2t λ
2 +
136
(1719
2+ 756 ζ3)y4
t λ2 +
9724y2
t λ3 +
11296
(3588 + 2016 ζ3)λ4],
where ζ3 = 1.20206... is the Riemann zeta function.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 176
Comparing 2–loop, 3–loop gaugeless and 3-loop full running of λChetyrkin, Zoller 2013
Important fact: in gaugeless limit using my MS input parameters leads to anunstable Higgs potential, while accounting for the complete calculation Ifind a stable vacuum up to MPlanck.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 177
° Matching conditions for MS parameters in terms of physicalparameters
v we want to solve the RG equations up to very high scales, where mass ef-fects are supposed to be negligible, in regions where physical thresholdsplay no role. The mass independent MS scheme is the most simple choiceand under these circumstances likely a rather physical one (reflects thetrue UV structure of the SM, quasi-bare quantities).
v in order to solve the MS RG equations we need the input MS values of the
basic couplings g′, g, g3, yt, λ. While g3(M2Z) =
√4 παs(M2
Z) is a standard MSreference parameter, the key parameters yt and λ are known actually onlythrough the related masses Mt and MH.
v therefore the relation between the renormalized on-shell masses and theirMS version provides natural matching conditions
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 178
The relation between the MS and the OS scheme we find by writing therelation between the renormalized and the bare masses (in the bareLagrangian) in the two schemes: for bosons
m2b bare
OS= M2
b ren + δM2b
MS= m2
b ren + δm2b
=⇒ m2b ren = M2
b ren +(δM2
b − δm2b
)i.e. the mass shift is given by the MS finite part prescription applied to the(UV singular) OS mass counterterm:
m2b
∣∣∣MS − M2
b
∣∣∣OS = δM2
b
∣∣∣2ε−γ+ln 4π+ln µ2
0→ln µ2 .
for bosons andm f
∣∣∣MS − M f
∣∣∣OS = δM f
∣∣∣2ε−γ+ln 4π+ln µ2
0→ln µ2 .
for fermions.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 179
Explicit SM one-loop expressions Fleischer, F.J. 1981
δMt = Mt C(−
169
s2W M2
W + 2M4
Z
M2H
+ 4M4
W
M2H
−1
18M2
Z −299
M2W +
169
M4W
M2Z
+A0(MH) + A0(MW) (12
+ 6M2
W
M2H
−12
M2b
M2t−
M2W
M2t
)
+A0(MZ) (3M2
Z
M2H
−1718
M2Z
M2t
+209
M2W
M2t−
169
M2W
M2Z
M2W
M2t
) + A0(Mt) 4 s2W (
43
M2W
M2t
)
+A0(Mt) (1 +1718
M2Z
M2t−
209
M2W
M2t
+169
M2W
M2Z
M2W
M2t
) + A0(Mb) (12
+12
M2b
M2t
+M2
W
M2t
)
+B0(Mt,MH,M2t ) (2 M2
t −12
M2H)
+B0(Mt,MZ ,M2t ) (−
718
M2Z −
1718
M4Z
M2t
+409
M2W +
209
M2W
M2Z
M2t−
329
M4W
M2Z
−169
M4W
M2t
)
+B0(Mb,MW ,M2t ) (
12
M4b
M2t− M2
b +12
M2t +
12
M2W
M2t
M2b +
12
M2W −
M4W
M2t
)
∑fs
A0(m f ) (−4m2
f
M2H
))
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 180
δM2H = C
(A0(MH) (3 M2
H)
+A0(MZ) (M2H + 6 M2
Z)
+B0(MH,MH,M2H) (
92
M4H)
+B0(MZ ,MZ ,M2H) (
12
M4H − 2 M2
H M2Z + 6 M4
Z)
+A0(MW) (2 M2H + 12 M2
W)
+B0(MW ,MW ,M2H) (M4
H − 4 M2H M2
W + 12 M4W)
+∑fs
[A0(m f ) (−8 m2
f ) + B0(m f ,m f ,M2H) (2 M2
H m2f − 8 m4
f )])
A0(m) = −m2(Reg + 1 − ln m2)
B0(m1,m2; s) = Reg −∫ 1
0dz ln(−sz(1 − z) + m2
1(1 − z) + m22z − iε) ,
are the basic scalar integrals with
Reg =2ε− γ + ln 4π + ln µ2
0 ≡ ln µ2 ; C =
√2 Gµ
16 π2 ; c2W =
M2W
M2Z
; s2W = 1 − c2
W
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 181
The on-loop corrections give the dominant contribution in the matchingrelations. Two-loop results are partially known F.J., Kalmykov, Veretin2002/.../2004. The expressions include the tadpole contributions andtherefore are gauge invariant and have the proper UV singularity structure.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 182
o Matching relation for the effective Fermi constant
On-shell counterterms:Using the relation
√2Gµ = v−2 = e2
4M2
ZM2
W
1M2
Z−M2W
one may write
δGFGF
= 2δv−1
v−1
δv−1
v−1 =δee−
1
2 s2W
(s2WδM2
W
M2W
+ c2WδM2
Z
M2Z
)δee
= C s2W M2
W
(383
+ 14A0(MW)
M2W
−83
∑fs
Q2f(1 +
A0(m f )
m2f
))
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 183
δM2Z = C
(−
23
M2H M2
Z + 4M4
Z
M2H
M2Z −
29
M4Z + 8
M4W
M2H
M2Z −
209
M2W M2
Z +163
M4W − 16 c2
W M4W
+A0(MH) (13
M2H + 2 M2
Z) + A0(MZ) (−13
M2H + 6
M4Z
M2H
+23
M2Z)
+A0(MW) (12M2
W
M2H
M2Z +
163
M2W − 16 c2
W M2W +
23
M2Z)
+B0(MZ ,MH,M2Z) (−
43
M2H M2
Z +13
M4H + 4 M4
Z)
+B0(MW ,MW ,M2Z) (
163
M2W M2
Z −683
M4W − 16 c2
W M4W +
13
M4Z)
+∑fs
[(323
M2Z m2
f −169
M4Z) (a2
f + b2f )
+ A0(m f ) (−8M2
Z
M2H
m2f +
323
M2Z (a2
f + b2f ))
+ B0(m f ,m f ,M2Z) (
323
M2Z m2
f (a2f − 2b2
f ) +163
M4Z (a2
f + b2f ))
])F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 184
δM2W = C
(−
23
M2H M2
W + 8M6
W
M2H
+ 4M4
Z
M2H
M2W −
1129
M4W −
23
M2Z M2
W + A0(MH) (2 M2W +
13
M2H)
+A0(MZ) (6M2
Z
M2H
M2W +
83
M2W − 8 c2
W M2W +
13
M2Z) + A0(MW) (12
M4W
M2H
− 4 M2W −
13
M2H −
13
M2Z)
+B0(MH,MW ,M2W) (−
43
M2H M2
W +13
M4H + 4 M4
W)
+B0(MZ ,MW ,M2W) (−
683
M4W − 16 c2
W M4W +
13
M4Z +
163
M2Z M2
W)
+B0(0,MW ,M2W) (−16 s2
W M4W)
+∑fd
[43
M2W (m2
1 + m22) −
49
M4W
+ A0(m1) (−8M2
W
M2H
m21 +
43
M2W −
23
(m21 − m2
2))
+ A0(m2) (−8M2
W
M2H
m22 +
43
M2W +
23
(m21 − m2
2))
+ B0(m1,m2,M2W) (
43
M4W −
23
M2W (m2
1 + m22) −
23
(m21 − m2
2)2)])
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 185
FromGF bare = Gµ + δGF
we then obtainGMS
F = Gµ + (δGF |OS)Reg=ln µ2
Below we will argue to use µ = MZ as a matching scale.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 186
o The issue of tadpoles and non-decoupling of heavy particlesor
tricky points in the Higgs phase of the SM
In the symmetric phase of the SM all masses except the m2–term in theHiggs potential vanish and the RG coefficient calculations and the solutionof the RG are straight forward as there are no special mass-couplingrelations and decoupling of heavy states (the four Higgs scalars) is asexpected according to the Appelquist-Carazzone theorem (AC), which inthe broken phase only holds in the QCD and QED sectors.
The Decoupling Theorem: if all external momenta of a process or in the cor-responding amplitude are small relative to the mass M of a heavy state, thenthe “light fields only” Green functions of the full theory differ from the theorywhich has no heavy fields at all, only by finite renormalizations of couplings,masses and fields of the light theory, up to terms which are suppressed byinverse powers of the heavy mass. Thus further corrections are of the form(µ/M)x with x ≥ 1.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 187
It means that only the renormalization subtraction constants are de-pendent on M (logarithms) and this M–dependence gets renormalizedaway by physical subtraction conditions.
As a S -matrix does not exist in the symmetric phase (IR problems) there isno on-shell renormalization scheme and the intrinsically massless MSscheme is the natural choice.
All couplings, the gauge couplings g′, g, gs, the Yukawa couplings y f , as wellas the Higgs self-coupling λ are dimensionless and run because oflogarithmic UV behavior.
The renormalization of the Higgs potential mass term m2 (the only relevantoperator in the Lagrangian) requires to remove the quadratic divergences,and hence potentially is subject to a hierarchy problem. The scaledependence of the renormalized m2 is ruled by its mass anomalousdimension.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 188
For m2 < 0 the Higgs mechanism takes place and implies a non-trivialvacuum characterized by a non-vanishing VEV (order parameter)
Hs = v + H ; 〈Hs〉 = v ; 〈H〉 = 0 ,
Hs is the original Higgs field of the symmetric phase H is the physical Higgsfield of mass MH. The condition
〈H〉 = 0
is not stable under renormalization, as we are in the broken phase, while anon-zero VEV is forbidden in the symmetric phase by the
discrete Z2 symmetry H → −H .
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 189
In perturbation theory contributions to 〈H〉 are the tadpoles :
〈H〉 = + = 0
ΠµνV (k2) ≡ +
Σf (k2) ≡ +
ΠH(k2) ≡ +
and appear as a contribution to the irreducible self-energies of all massiveparticles.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 190
At one loop in the SM the tadpole counterterm needed to adjust 〈H〉 = 0 is
δvtp = v1
16π2v2
1M2
H
[−2M4
Z − 4M2W + A0(MH) (−
32
M2H) + A0(MZ) (−3 M2
Z)
+A0(MW) (−6 M2W) + A0(
√ξMZ) (−
12
M2H) + A0(
√ξMW) (−M2
H)
+∑
f
4 M2f A0(M f )
]where ξ is the gauge parameter in the linear ’t Hooft gauge.
r tadpoles are UV singular
r tadpoles are not gauge invariant
Consequently, mass counter terms, like
Γ(2)H = i
[p2 − M2
H ren − δM2H + ΠH(p2)
]; δM2
H = ΠH
(M2
H ren
)F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 191
are gauge invariant only if tadpoles are included. This is a controversialpoint, because there is a theorem saying that tadpoles do never contributeto physical observables! J.C. Taylor 1976, E. Kraus 1998
The no-Tadpoles Theorem: Physical amplitudes as functions of phys-ical parameters are devoid of tadpoles.
That’s why very often in higher order calculations tadpole contributions areomitted as contributions.
Our point of view: taking into account all diagrams according to SMFeynman rules cannot be wrong. If at the end it turns out that tadpolescancel in a given calculation the result remains the same.
At the end the upshot of SBGT is thatthe UV renormalization structure is not affected by spontaneous SB
and thus identical in both the symmetric and the broken phase.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 192
Omitting tadpoles implies:à the relations between bare and renormalized parameters get messed up,
UV structure lost, gauge invariance lost
à as MS quantities are directly extracted from the bare ones, also therelationship between MS and on-shell quantities are affected.Such pseudo MS quantities do not satisfy the correct RG equationand they are gauge dependent
à the RG equations in the symmetric phase, where all counterterms aredevoid of tadpoles, can be reproduced from the mass counterterms,calculated in the broken phase, via the bare mass-coupling relations:
m2W(µ2) = 1
4 g2(µ2) v2(µ2) ; m2
Z(µ2) = 14 (g2(µ2) + g′2(µ2)) v2(µ2) ;
m2f (µ
2) = 12 y
2f (µ
2) v2(µ2) ; m2H(µ2) = 1
3 λ(µ2) v2(µ2) .
which tell us that at fixed v a particle can be heavy only in the correspondingstrong coupling limit, in which large effects are unavoidable.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 193
From these relations we derive the key relations
µ2 ddµ2v
2(µ2) = 4 µ2 ddµ2
m2W(µ2)g2(µ2)
= 4 µ2 ddµ2
m2Z(µ2) − m2
W(µ2)g′2(µ2)
= 3 µ2 d
dµ2
m2H(µ2)λ(µ2)
= 2 µ2 ddµ2
m2f (µ
2)
y2f (µ
2)
= v2(µ2)[γm2 −
βλλ
],
which relates the RG for the order parameter v to the parameters m and λ ofthe Higgs potential. Surprising or not the β-function related to v exhibitsnon-analytic terms in λ of the form βλ
λ. The terms originate from the 1
M2H
(zero
momentum transfer Higgs propagator) factor of the contributing tadpoles4.
Ü lesson 1: tadpoles can produce large shifts in the relations betweenthe “quasi-bare” MS parameters and the on-shell ones and are neces-sary to preserve gauge invariance and the correct RG equations
4In the pure Higgs system, where β(λ) ∝ λ there would be no problem because βλ/λ would be regular at λ = 0. Inthe SM βλ|λ=0 = βλ(g, g′, gs, yt, λ = 0) , 0 and we would have a true pole.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 194
For the weak sector of the SM is important that, besides the tadpole issue,that the AC-theorem does not apply:
l the non-decoupling in the weak sector of the SM is a consequence of themass coupling relations, which hold if the masses are generated by theHiggs mechanism
l in QCD the MS scheme is utilized in conjunction with “decoupling byhand” considering an effective ’n f active flavors’ QCD to be matched atsuccessive flavor thresholds
l there is no decoupling for the W and Z bosons: the limit MW → ∞ can beachieved by letting g→ ∞ or v→ ∞ or both. In nature, only the limit g→ ∞leads to the observed low-energy limit of the effective four-fermion theorywith
√2 Gµ = 1/v2 fixed, by nuclear β–decay etc. This obviously is a
non-decoupling effect. In contrast to QED or QCD, the low-energy effectivetheory (obtained after elimination of the heavy state) is a non-renormalizableone exhibiting a completely wrong high-energy behavior
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 195
l most well-known non-decoupling effects due to heavy top mass
à leading correction in EW ρ parameter
ρ = GNC/GCC(0) = 1 +NcGµ
8π2√
2
m2t + m2
b −2m2
t m2b
m2t − m2
b
lnm2
t
m2b
≈ 1 +Ncy
2t
32π2 ,
measures weak-isospin breaking by the Yukawa couplings of the heavyfermions at zero momentum.
1995 LEP bound on Mt Ü 1995 Top discovery at Tevatron
Ü lesson 2: “decoupling by hand” cannot be applied for weak con-tributions, i.e., we cannot parametrize and match together effectivetheories by switching off fields of mass M > µ at a given scale µ.
l potentially, the Higgs VEV v, which determines the Fermi constant viaGF = 1
√2v2
, could be particularly affected by non-decoupling effects
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 196
However, we may take advantage of the fact that tadpole contributions dropout from relations between physical (on-shell) parameters and amplitudes:
o compare:
à low energy – Gµ determined by the muon lifetime
à W mass scale – Gµ =12πΓW`ν√
2M3W
given by leptonic W decay rate.
Indeed: Gµ ≈ Gµ with good accuracy is not surprising because the tadpolecorrections which potentially lead to substantial corrections are absent inrelations between observable quantities as we know.
o consequently a SM parametrization in terms of α(MZ), αs(MZ),Gµ and MZ
(besides the other masses), provides a good parametrization of theobservables extracted from experiments at the vector boson mass scale(LEP precision physics).
o While α(MZ) and αs(MZ) are strongly scale dependent, Gµ remains
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 197
unrenormalized below the Z mass scale, which thus is an ideal matchingscale, to evaluate the MS parameters in terms of corresponding on-shellvalues.
r Usually the scale independence of the effective GF below the W massscale is “explained” by a “decoupling by hand” argument by inspection ofthe one-loop RG equation
µ2 d ln GMSF
dµ2 =
√2 GMS
F
8π2
{∑f
(m2f − 4
m4f
m2H
) − 3 m2W + 6
m4W
m2H
− 3/2 m2Z + 3
m4Z
m2H
+ 3/2 m2H
},
If we sum terms only over m < µ, there is effectively no running, because ofthe smallness of the light fermion masses. GF is expected to start runningonce MW, MZ, MH and Mt come into play. At higher scales, certainly, the MSversion of v(µ2) or equivalently GMS
F (µ2) must be running as required by thecorresponding RG.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 198
o Matching and running of the top mass
r quark masses in the MS scheme
mq,bare = mq(µ2)[1 + αs
∑i=0
αis
i+1∑k=1
δZ(i,k)αs
.k+ α
∑i, j=0
αiαjs
i+ j+1∑k=1
δZ(i, j,k)α
.k
].
incl. QCD corrections, EW contribution mixed in higher orders with QCD
r quark mass anomalous dimension
µ2 ddµ2 ln m2
q = γq(αs, α) =
[αs
∂
∂αs+ α
∂
∂α
] [αs
∑i=0
αisδZ
(i,1)αs
+α∑i, j=0
αiαjsδZ
(i, j,1)α
],
split into the pure QCD plus all others, which we call EW contributionsγq(αs, α) = γQCD
q + γEWq , the EW contribution to the fermion anomalous
dimension γEWt in the MS scheme may be written in terms of
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 199
RG functions of parameters in the unbroken phase of the SM asγEW
t = γyt + 12γm2 −
12βλλ,
where γm2 = µ2 ddµ2 ln m2, βλ = µ2 d
dµ2λ, γyq = µ2 ddµ2 ln yq, yq is the Yukawa coupling
of quark q, and m2 and λ are the parameters of the scalar potentialV = m2
2 φ2 + λ
24φ4.
r RG equation for Higgs VEV v(µ2) follows
µ2 ddµ2v
2(µ2) = v2(µ2)[γm2 −
βλλ
],
r the anomalous dimension of GMSF is γGF = −
[γm2 −
βλλ
],
Note: the anomalous dimension of v2(µ2) adopted here via diagrammaticcalculations differs from the anomalous dimension of the scalar field asobtained in the effective-potential approach.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 200
r matching conditions between pole and running masses
Mt − mt(µ2) = mt(µ2)∑j=1
(αs(µ2)π
) j
ρ j + mt(µ2)∑
i=1; j=0
(α(µ2)π
)i (αs(µ2)π
) j
ri j .
The QCD corrections ρ j ( j = 2, 3) Gray, Broadhurst, Grafe, Schilcher 1990;Fleischer, F.J., Tarasov, Veretin 1999; Chetyrkin, Steinhauser 1999/2000;Melnikov, Ritbergen 2000 r10 Hempfling, Kniehl 1995 and r11 F.J., Kalmykov2003/2004 r12 in the gaugeless-limit Martin 2005
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 201
Numerical result for mt − Mt
F.J., Kalmykov, Kniehl 2012
{mt(M2
t ) − Mt
}QCD
= Mt
[−
43α(6)
s (M2t )
π− 9.125
α(6)s (M2
t )π
2
− 80.405
α(6)s (M2
t )π
3].
Using α(6)s (M2
t ) = 0.1079(6), which follows from the value of α(5)s (M2
Z) viafour-loop evolution and three-loop matching we obtain the numerical result{
mt(M2t ) − Mt
}QCD
= −7.95 GeV − 1.87 GeV − 0.57 GeV = −10.38 GeV .
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 202
Numerical results for the difference mt(M2t ) − Mt
The two-loop corrections of order O(α2) are not yet. The largest contributionis coming from tadpole diagrams, which are known and allows us toestimate the error due to the unknown higher-order corrections, which isabout 1 GeV.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 203
The various contributions to mt(M2t ) − Mt in GeV.
MH [GeV] O(α) O(ααs) O(α) + O(ααs) O(αs) + O(α2s) + O(α3
s) total124 12.11 −0.39 11.72 −10.38 1.34125 11.91 −0.39 11.52 −10.38 1.14126 11.71 −0.38 11.32 −10.38 0.94
As a result, we observe a large EW correction, which for the assumed MH
range by accident almost perfectly cancels the QCD correction. The relationmt(M2
t ) vs. Mt can be parametrized as
{mt(M2
t )−Mt
}SM
={mt(M2
t )−Mt
}QCD
+
[0.0664−0.00115 ×
( MH
1 GeV−125
)]Mt .
Our calculation shows that the large leading correction, of O(α), to the shiftmt(M2
t ) − Mt is not substantially modified by the next-to-leading term, ofO(ααs). Radiative corrections beyond the presently known ones are likely tobe small and not to change the observed quenching qualitatively.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 204
o The top Yukawa coupling from form Mt
Once again:
In the weak sector of the SM, there is no decoupling because massesand couplings are interrelated by the Higgs mechanism. So “decou-pling by hand” as usually applied in QCD by considering an effective‘n f active flavors’ QCD to be matched at successive flavor thresholds,and which can be applied to QED as well, does not make sense in theweak sector.
On phenomenological grounds, as GF has been measured to agree at the MZ
scale with its low energy version Gµ and because Yukawa couplings run asthey do in the symmetric phase, below of the EW scale, one may defineeffective light fermion masses to run via their Yukawa couplings only:
m f (µ2) = 2−3/4G−1/2µ y f (µ2) .
l As the Yukawa couplings y f (µ2) are not affected by the Higgs mechanism,
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 205
the EW corrections to the Yukawa couplings are free of tadpoles and/orquadratic divergences.
l Since real physical observables are also free of tadpole contributions, thisproperty is an additional argument why the advocated relation is a goodcandidate for the evaluation of the EW contributions to the ratio betweenpole and MS masses of lighter quarks, such as the bottom and charm quarks
r In short: fermion masses and Yukawa couplings have equivalent RGevolution as long as GF or, equivalently, v can be taken not to be running and
identify GMSF (µ2) = Gµ.
l Alternatively, and more consequently concerning the decoupling issue,the proper MS definition of a running fermion mass is
m f (µ2) = 2−3/4(GMS
F
)−1/2(µ2) y f (µ2) , (F)
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 206
where GMSF (µ2) and m f (µ2) are solutions of
γGF = µ2 ddµ2 ln GMS
F (µ2) = −µ2 ddµ2 ln v2(µ2) = −
[γm2 −
βλλ
],
and
µ2 ddµ2 ln m f (µ2) = γQCD
q + γy f −12γGF ,
respectively. For the MS top quark mass we advocate to use (F), whichamong others includes the tadpole contributions.
à Note that the difference between the two definitions is particularlysignificant for the top quark. As both versions are gauge invariant bydefinition, the difference is not just dropping or not the tadpole terms.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 207
The running of GMSF definitely starts at about µ ∼ 2MW
5, when the scale of aprocess exceeds the masses of the weak gauge bosons. Since the topquark is the heaviest particle in the SM, at least here the “decoupling byhand” prescription becomes obsolete and we have to take full SM parameterrelations as they are.
The top Yukawa coupling running up to MPlanck
5As the on-shell GF at the Z boson mass scale can be identified with Gµ (numerically) it is justified to match GMSF
with Gµ at the scale MZ.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 208
o The Higgs self-coupling form MH
Note that the only information we have on the Higgs self-coupling λ is viathe experimental value of MH:
λ = 3√
2Gµ M2H.
From the physical Higgs mass MH and the relation
m2H = M2
H +(δM2
H
∣∣∣OS
)Reg=ln µ2
one may evaluate the relation between λ and λMS under the proviso thatGMS
F = Gµ ??? . In principle GMSF is expected to be a running parameter as
well. As argued above indeed up to the W boson mass scale GMSF can be
taken not to run. The result of the evaluation may be parametrized as
λ(MH) = 0.8065 + 0.0109 (MH[GeV] − 126) + 0.0015 (Mt[GeV] − 172) +0.0002−0.006 ,
central value refers to µ = MH. Fleischer, F.J. 1981, Sirlin, Zucchini 1986
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 209
2-loop matching
The QCD contribution, λ(2)QCD(µ), is obtained evaluating the relevant diagrams
via a Taylor series in xht ≡ m2h/m
2t up to fourth order
λ(2)QCD(µ) = 6 ×
G2µm
4t
(4π)4 Nc CF g23(µ)
[16
(−4 − 6LT + 3L2
T
)+ xht
(35 −
2 π2
3+ 12LT − 12L2
T
)+ x2
ht61135
+ x3ht
12236300
+ x4ht
431231323000
],
where Nc and CF are color factors (Nc = 3, CF = 4/3) and LT = ln(m2t /µ
2).Bezrukov et al 2012, Degrassi et al 2012
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 210
The Higgs self-coupling in comparison with the other couplings
With my input values for the MSb parameters (which slightly differ in thetop-Yukawa coupling) I get a stable Higgs vacuum i.e. λ(µ) remains positiveup to MPlanck such that the SM can be valid by itself up to the Planck scale.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 211
RG behavior of the Higgs VEV
v For large values of µ2, the behavior of the running Fermi constant GF(µ2) isdefined by the Higgs self-coupling and the sign of its beta-function βλ:
µ2 ddµ2 ln GF(µ2) ∼
βλ(µ2)λ(µ2)
.
v The detailed perturbative analysis of the r.h.s. of this equation was per-formed recently and reveals that the beta function βλ is negative up to ascale of about 1017 GeV, where it changes sign. Above the zero of βλ, theeffective coupling starts to increase again, and the key question is whetherat the zero of the beta function the effective coupling is still positive. In thelatter case, it will remain positive although small up to the Planck scale.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 212
v In any case, at moderately high scales where βλ < 0, and provided that λ isstill positive, the following behavior is valid for the Fermi constant:
GF(µ2)∣∣∣µ2→∞
∼(µ2
)βλ(µ2)λ(µ2) → 0 ,
being decreasing, which means that v2(µ2) is increasing at these scales(where βλ < 0 and λ > 0).
v Most of the recent analyses of find that λ turns negative (unstable or meta-stable Higgs potential) before the beta function reaches its zero. This mayhappen at rather low scales, at around 1010 GeV. In this case, we would getan infinite Higgs vacuum expectation value far below the Planck scale asan essential singularity.
v Given the present uncertainty in the value of Mt, there is a good chance
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 213
that λ remains positive up to the zero of the beta function and as a conse-quence up to the Planck scale.
v Then GF(µ2) would start to increase again, and v(µ2) would start to decreasebut remain finite (about 685 GeV) at the Plank scale, implying that all effec-tive masses stay bounded.
v The effectively massless symmetric phase of the SM would then be ob-tained at high energies by the fact that mass effects are suppressed fordimensional reasons: according to the RG, for a vertex function under adilatation of all momenta, {pi} → {κpi}, up to the overall dynamical dimen-sion and wave-function renormalizations, the result is given by replacinggi → gi(κ) and mi → mi(κ)/κ at fixed {pi} and renormalization scale µ. I.e.provided that m(κ)/κ → 0 as κ → ∞, the high-energy asymptotic effectivetheory is effectively massless as expected in the symmetric phase.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 214
102 104 106 108 1010 1012 1014 1016 1018 1020
0.0
0.2
0.4
0.6
0.8
1.0
RGE scale Μ in GeV
SM
coupli
ngs
g1
g2
g3yt
Λyb
m in TeV
Renormalization of the SM gauge couplings g1 =√
5/3gY , g2, g3, of the top,bottom and τ couplings (yt, yb, yτ), of the Higgs quartic coupling λ and of theHiggs mass parameter m. All parameters are defined in the MS scheme. Weinclude two-loop thresholds at the weak scale and three-loop RG equations.
The thickness indicates the ±1σ uncertainties in Mt,Mh, α3.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 215
At the Planck mass, Degrassi et al. 2013 find the following SM parameters:
g1(MPlanck) = 0.6168
g2(MPlanck) = 0.5057
g3(MPlanck) = 0.4873 + 0.0002α3(MZ) − 0.1184
0.0007
yt(MPlanck) = 0.3823 + 0.0051( Mt
GeV− 173.35
)− 0.0021
α3(MZ) − 0.11840.0007
λ(MPlanck) = −0.0128 − 0.0065( Mt
GeV− 173.35
)+
+0.0018α3(MZ) − 0.1184
0.0007+ 0.0029
( Mh
GeV− 125.66
)m(MPlanck) = 140.2 GeV + 1.6 GeV
( Mh
GeV− 125.66
)+
−0.25 GeV( Mt
GeV− 173.35
)+ 0.05 GeV
α3(MZ) − 0.11840.0007
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 216
Addendum: Complete NNLO RG for Higgs potential parameters λ and m2
β(1)λ
= − y4τ − y
4b3 + g4
2916
+ g21g
22
38
+ g41
316
+ λy2τ2 + λy2
b6 − λg22
92− λg2
132
+ λ212 + y2t λ6 − y4
t 3 ,
β(2)λ
=y6τ5 + y6
b15 − g42y
2τ
38− g4
2y2b
98
+ g62
(49732− 2Ng
)− g2
1y4τ2 + g2
1y4b
23
+ g21g
22y
2τ
114
+ g21g
22y
2b
94− g2
1g42
(9796
+23
Ng
)− g4
1y2τ
258
+ g41y
2b
58
− g41g
22
(23996
+109
Ng
)− g6
1
(5996
+109
Ng
)− λy4
τ12− λy4
b32
+ λg22y
2τ
154
+ λg22y
2b
454
+ λg42
(−
31316
+ 5Ng
)+ λg2
1y2τ
254
+ λg21y
2b
2512
+ λg21g
22
398
+ λg41
(22948
+259
Ng
)− λ2y2
τ24 − λ2y2b72 + λ2g2
254
+ λ2g2118 − λ3156 − y2
t y4b3 − y2
t g42
98
+ y2t g
21g
22
214− y2
t g41
198
− y2t λy
2b21 + y2
t λg22
454
+ y2t λg
21
8512− y2
t λ272 − y4
t y2b3 − y4
t g21
43
− y4t λ
32
+ y6t 15 − g2
sy4b16 + g2
sλy2b40 + g2
sy2t λ40 − g2
sy4t 16.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 217
β(3)λ
=y8τ
(−
1438− 12ζ3
)− y2
by6τ
2978− y4
by4τ72 − y6
by2τ
2978
+ y8b
(−
15998− 36ζ3
)+ g2
2y6τ
(113732− 9ζ3
)+ g2
2y6b
(341132− 27ζ3
)+ g4
2y4τ
(4503128
−27316
ζ3 −134
Ng
)+ g4
2y2by
2τ
98
+ g42y
4b
(13653128
−81916
ζ3 −394
Ng
)+ g6
2y2τ
(−
5739256
+994ζ3 +
92
Ng
)+ g6
2y2b
(−
17217256
+2974ζ3 +
272
Ng
)+ g8
2
(9822913072
−2781128
ζ3 −14749192
Ng
−45Ngζ3 −53
N2g
)+ g2
1y6τ
(13532
+ 33ζ3
)+ g2
1y6b
(511196− 25ζ3
)+ g2
1g22y
4τ
(−
1564−
3818ζ3
)− g2
1g22y
2by
2τ
54
+ g21g
22y
4b
(−
3239192
−3118ζ3
)+ g2
1g42y
2τ
(1833256
−32ζ3 −
12
Ng
)+ g2
1g42y
2b
(4179256
+ 9ζ3 +52
Ng
)+ g2
1g62
(−
540533456
−40532
ζ3 −8341864
Ng −1027
N2g
)+ g4
1y4τ
(5697128
+37516
ζ3 +6512
Ng
)+ g4
1y2by
2τ
4124
+ g41y
4b
(151373456
−2035144
ζ3 −41536
Ng
)+ g4
1g22y
2τ
(6657256
−152ζ3 −
56
Ng
)(1)
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 218
+ g41g
22y
2b
(4403256
+92ζ3 +
256
Ng
)+ g4
1g42
(−
646933456
+87364
ζ3 +149648
Ng + 7Ngζ3
−5081
N2g
)+ g6
1y2τ
(3929256
−154ζ3 +
556
Ng
)+ g6
1y2b
(120432304
+54ζ3 +
9518
Ng
)+ g6
1g22
(−
297796912
+7532ζ3 −
180012592
Ng +619
Ngζ3 −250243
N2g
)+ g8
1
(−
68459216
+99
128ζ3 −
207351728
Ng +959
Ngζ3 −12581
N2g
)+ λy6
τ
(−
12418− 66ζ3
)+ λy2
by4τ240 + λy4
by2τ240 + λy6
b
(1178− 198ζ3
)+ λg2
2y4τ
(−
15878
+ 171ζ3
)− λg2
2y2by
2τ27 + λg2
2y4b
(−
49778
+ 513ζ3
)+ λg4
2y2τ
(−
131164−
1172ζ3 −
214
Ng
)+ λg4
2y2b
(−
393364−
3512ζ3 −
634
Ng
)+ λg6
2
(−
46489288
+2259
8ζ3 +
351536
Ng
+90Ngζ3 +709
N2g
)+ λg2
1y4τ
(5078− 117ζ3
)− λg2
1y2by
2τ9 + λg2
1y4b
(−
573724
+249ζ3)
+ λg21g
22y
2τ
(−
377132
+ 126ζ3
)+ λg2
1g22y
2b
(−
300932
+ 12ζ3
)(2)
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 219
+ λg21g
42
(455332−
2498ζ3 +
332
Ng − 6Ngζ3
)+ λg4
1y2τ
(−
178364−
1232ζ3 −
654
Ng
)+ λg4
1y2b
(−
1273031728
−476ζ3 −
15536
Ng
)+ λg4
1g22
(9798−
38ζ3 +
954
Ng − 6Ngζ3
)+ λg6
1
(12679
432+
98ζ3 +
5995162
Ng −190
9Ngζ3 +
1750243
N2g
)+ λ2y4
τ
(7172
+ 252ζ3
)− λ2y2
by2τ216 + λ2y4
b
(1719
2+ 756ζ3
)+ λ2g2
2y2τ
(2134− 144ζ3
)+ λ2g2
2y2b
(6394
−432ζ3)
+ λ2g42
(1995
8− 513ζ3 − 141Ng
)+ λ2g2
1y2τ
(−
5414
+ 96ζ3
)+ λ2g2
1y2b
(417
4− 192ζ3
)+ λ2g2
1g22(−333 − 162ζ3
)+ λ2g4
1(−183 − 81ζ3
−2353
Ng
)+ λ3y2
τ291 + λ3y2b873 + λ3g2
2(−474 + 72ζ3
)+ λ3g2
1(−158 + 24ζ3
)+ λ4 (
3588 + 2016ζ3)
+ y2t y
6τ
(−
2978
)+ y2
t y2by
4τ12 + y2
t y4by
2τ
458
+ y2t y
6b
(−
7178
−36ζ3)
+ y2t g
22y
4b
47732
+ y2t g
42y
2τ
98
+ y2t g
42y
2b
(−
35164
+117
2ζ3 − 12Ng
)(3)
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 220
+ y2t g
62
(−
17217256
+2974ζ3 +
272
Ng
)+ y2
t g21y
4b
(−
229996
+ 26ζ3
)+ y2
t g21g
22y
2τ
294
+ y2t g
21g
22y
2b
(1001
96+
312ζ3
)+ y2
t g21g
42
(3103256
+274ζ3 +
12
Ng
)+ y2
t g41y
2τ
70124
+ y2t g
41y
2b
(−
70964− ζ3
)+ y2
t g41g
22
(23521768
− 3ζ3 +56
Ng
)+ y2
t g61
(429432304
−52ζ3 +
21518
Ng
)+ y2
t λy4τ240 + y2
t λy2by
2τ21
+ y2t λy
4b
(6399
8+ 144ζ3
)− y2
t λg22y
2τ27 + y2
t λg22y
2b
(−
5314
+ 54ζ3
)+ y2
t λg42
(−
393364−
3512ζ3 −
634
Ng
)− y2
t λg21y
2τ9 + y2
t λg21y
2b
(−
92912− 2ζ3
)+ y2
t λg21g
22
(−
650932
+ 177ζ3
)+ y2
t λg41
(−
1124471728
−449
6ζ3 −
63536
Ng
)− y2
t λ2y2τ216 + y2
t λ2y2
b(117 − 864ζ3
)+ y2
t λ2g2
2
(6394− 432ζ3
)+ y2
t λ2g2
1
(−
1954− 48ζ3
)+ y2
t λ3873 − y4
t y4τ72 + y4
t y2by
2τ
458
+ y4t y
4b72ζ3
(4)
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 221
+ y4t g
22y
2b
47732
+ y4t g
42
(13653128
−81916
ζ3 −394
Ng
)+ y4
t g21y
2b
(1337
96− 28ζ3
)+ y4
t g21g
22
(−
1079192
−743
8ζ3
)+ y4
t g41
(1009133456
+2957144
ζ3 −11536
Ng
)+ y4
t λy2τ240 + y4
t λy2b
(6399
8+ 144ζ3
)+ y4
t λg22
(−
49778
+ 513ζ3
)+ y4
t λg21
(−
248524
+ 57ζ3
)+ y4
t λ2(1719
2+ 756ζ3
)− y6
t y2τ
2978
+ y6t y
2b
(−
7178− 36ζ3
)+ y6
t g22
(341132− 27ζ3
)+ y6
t g21
(346796
+ 17ζ3
)+ y6
t λ
(1178− 198ζ3
)+ y8
t
(−
15998− 36ζ3
)+ g2
sy6b(−38 + 240ζ3
)+ g2
sg22y
4b
(−
312
+ 24ζ3
)+ g2
sg42y
2b
(6518− 54ζ3
)+ g2
sg62
(−
1538
Ng + 18Ngζ3
)+ g2
sg21y
4b
(−
64118
+1363ζ3
)+ g2
sg21g
22y
2b
(233
4− 36ζ3
)+ g2
sg21g
42
(−
518
Ng + 6Ngζ3
)(5)
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 222
+ g2sg
41y
2b
(68324− 18ζ3
)+ g2
sg41g
22
(−
18724
Ng +223
Ngζ3
)+ g2
sg61
(−
18724
Ng
+223
Ngζ3
)+ g2
sλy4b(895 − 1296ζ3
)+ g2
sλg22y
2b
(−
4892
+ 216ζ3
)+ g2
sλg42
(1352
Ng − 72Ngζ3
)+ g2
sλg21y
2b
(−
99118
+ 40ζ3
)+ g2
sλg41
(552
Ng
−883
Ngζ3
)+ g2
sλ2y2
b(−1224 + 1152ζ3
)+ g2
sy2t y
4b(−2 − 48ζ3
)+ g2
sy2t g
22y
2b(−8 + 96ζ3
)+ g2
sy2t g
42
(6518− 54ζ3
)+ g2
sy2t g
21g
22
(2494− 36ζ3
)+ g2
sy2t g
41
(58724− 18ζ3
)+ g2
sy2t λy
2b(82 − 96ζ3
)+ g2
sy2t λg
22
(−
4892
+ 216ζ3
)+ g2
sy2t λg
21
(−
241918
+ 136ζ3
)+ g2
sy2t λ
2 (−1224 + 1152ζ3
)+ g2
sy4t y
2b(−2 − 48ζ3
)+ g2
sy4t g
22
(−
312
+ 24ζ3
)+ g2
sy4t g
21
(93118−
563ζ3
)+ g2
sy4t λ
(895 − 1296ζ3
)+ g2
sy6t(−38 + 240ζ3
)+ g4
sy4b
(−
6263
+ 32ζ3 + 40Ng
)(6)
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 223
+ g4sλy
2b
(1820
3− 48ζ3 − 64Ng
)+ g4
sy2t y
2b192 + g4
sy2t λ
(1820
3− 48ζ3 − 64Ng
)+ g4
sy4t
(−
6263
+ 32ζ3 + 40Ng
). (7)
β(1)m2
m2 =y2τ + y2
b3 − g22
94− g2
134
+ λ6 + y2t 3,
β(2)m2
m2 = − y4τ
94− y4
b274
+ g22y
2τ
158
+ g22y
2b
458
+ g42
(−
38532
+52
Ng
)+ g2
1y2τ
258
+ g21y
2b
2524
+ g21g
22
1516
+ g41
(+
15796
+2518
Ng
)− λy2
τ12 − λy2b36 + λg2
236 + λg2112
− λ230 − y2t y
2b
212
+ y2t g
22
458
+ y2t g
21
8524− y2
t λ36
− y4t
274
+ g2sy
2b20 + g2
sy2t 20,
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 224
β(3)m2
m2 =y6τ
(−
23316
+ 15ζ3
)+ y2
by4τ72 + y4
by2τ72 + y6
b
(160516
+ 45ζ3
)+ g2
2y4τ
(−
98716
+ 54ζ3
)− g2
2y2by
2τ
272
+ g22y
4b
(−
317716
+ 162ζ3
)+ g4
2y2τ
(−
255128−
814ζ3 −
218
Ng
)+ g4
2y2b
(−
765128−
2434ζ3 −
638
Ng
)+ g6
2
(−
39415576
+71116
ζ3 +286772
Ng + 45Ngζ3 +359
N2g
)+ g2
1y4τ
(29116− 36ζ3
)− g2
1y2by
2τ
92
+ g21y
4b
(−
106716
+ 72ζ3
)+ g2
1g22y
2τ
(−
233164
+ 45ζ3
)− g2
1g22y
2b
86564
+ g21g
42
(269164−
40516
ζ3 +214
Ng − 3Ngζ3
)+ g4
1y2τ
(−
3607128
−154ζ3 −
658
Ng
)+ g4
1y2b
(−
792073456
−3512ζ3 −
15572
Ng
)+ g4
1g22
(105332−
20716
ζ3 +558
Ng − 3Ngζ3
)+ g6
1
(839108−
5116ζ3 +
4375324
Ng −959
Ngζ3 +875243
N2g
)+ λy4
τ
(2614
+ 72ζ3
)
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 225
− λy2by
2τ108 + λy4
b
(351
4+ 216ζ3
)+ λg2
2y2τ
(1898− 108ζ3
)+ λg2
2y2b
(5678− 324ζ3
)+ λg4
2
(11511
32− 162ζ3 −
1532
Ng
)+ λg2
1y2τ
(−
5498
+ 36ζ3
)+ λg2
1y2b
(3938− 132ζ3
)+ λg2
1g22
(−
170116
+ 36ζ3
)+ λg4
1
(−
107732− 18ζ3 −
852
Ng
)+ λ2y2
τ992
+ λ2y2b
2972
+ λ2g22(−63 − 108ζ3
)+ λ2g2
1(−21 − 36ζ3
)+ λ31026 + y2
t y4τ72 + y2
t y2by
2τ
212
+ y2t y
4b
(404716
+ 36ζ3
)+ y2
t g22y
2τ
(−
272
)+ y2
t g22y
2b
(−
2438− 27ζ3
)+ y2
t g42
(−
765128−
2434ζ3 −
638
Ng
)− y2
t g21y
2τ
92
+ y2t g
21y
2b
(−
92924− ζ3
)+ y2
t g21g
22
(−
327764
+117
2ζ3
)+ y2
t g41
(−
1231033456
−14912
ζ3 −63572
Ng
)− y2
t λy2τ108
+ y2t λy
2b
(−
3152− 216ζ3
)+ y2
t λg22
(5678− 324ζ3
)+ y2
t λg21
(−
2198− 60ζ3
)+ y2
t λ2 297
2+ y4
t y2τ72 + y4
t y2b
(404716
+ 36ζ3
)+ y4
t g22
(−
317716
+ 162ζ3
)
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 226
+ y4t g
21
(−
43116
+ 12ζ3
)+ y4
t λ
(3514
+ 216ζ3
)+ y6
t
(160516
+ 45ζ3
)+ g2
sy4b
(447
2− 360ζ3
)+ g2
sg22y
2b
(−
4894
+ 108ζ3
)+ g2
sg42
(1354
Ng − 36Ngζ3
)+ g2
sg21y
2b
(−
99136
+ 20ζ3
)+ g2
sg41
(554
Ng −443
Ngζ3
)+ g2
sλy2b(−612 + 576ζ3
)+ g2
sy2t y
2b(41 − 48ζ3
)+ g2
sy2t g
22
(−
4894
+ 108ζ3
)+ g2
sy2t g
21
(−
241936
+ 68ζ3
)+ g2
sy2t λ
(−612 + 576ζ3
)+ g2
sy4t
(4472− 360ζ3
)+ g4
sy2b
(9103− 24ζ3 − 32Ng
)+ g4
sy2t
(9103− 24ζ3 − 32Ng
).
FFFFFFFFFF
Previous ≪x , next x≫ lecture.
F. Jegerlehner, IFJ-PAN, Krakow Lectures 2014, —≪x Lect. 3 x≫ 227